@article{BouamraZouhalRateletal.2022,
author = {Bouamra, Marwa and Zouhal, Hassane and Ratel, S{\´e}bastien and Makhlouf, Issam and Bezrati, Ikram and Chtara, Mokhtar and Behm, David G. and Granacher, Urs and Chaouachi, Anis},
title = {Concurrent training promotes greater gains on body composition and components of physical fitness than single-mode training (endurance or resistance) in youth with obesity},
series = {Frontiers in physiology},
volume = {13},
journal = {Frontiers in physiology},
publisher = {Frontiers Media},
address = {Lausanne},
issn = {1664-042X},
doi = {10.3389/fphys.2022.869063},
pages = {16},
year = {2022},
abstract = {The prevalence of obesity in the pediatric population has become a major public health issue. Indeed, the dramatic increase of this epidemic causes multiple and harmful consequences, Physical activity, particularly physical exercise, remains to be the cornerstone of interventions against childhood obesity. Given the conflicting findings with reference to the relevant literature addressing the effects of exercise on adiposity and physical fitness outcomes in obese children and adolescents, the effect of duration-matched concurrent training (CT) [50\% resistance (RT) and 50\% high-intensity-interval-training (HIIT)] on body composition and physical fitness in obese youth remains to be elucidated. Thus, the purpose of this study was to examine the effects of 9-weeks of CT compared to RT or HIIT alone, on body composition and selected physical fitness components in healthy sedentary obese youth. Out of 73 participants, only 37; [14 males and 23 females; age 13.4 +/- 0.9 years; body-mass-index (BMI): 31.2 +/- 4.8 kg center dot m-2] were eligible and randomized into three groups: HIIT (n = 12): 3-4 setsx12 runs at 80-110\% peak velocity, with 10-s passive recovery between bouts; RT (n = 12): 6 exercises; 3-4 sets x 10 repetition maximum (RM) and CT (n = 13): 50\% serial completion of RT and HIIT. CT promoted significant greater gains compared to HIIT and RT on body composition (p < 0.01, d = large), 6-min-walking test distance (6 MWT-distance) and on 6 MWT-VO2max (p < 0.03, d = large). In addition, CT showed substantially greater improvements than HIIT in the medicine ball throw test (20.2 vs. 13.6\%, p < 0.04, d = large). On the other hand, RT exhibited significantly greater gains in relative hand grip strength (p < 0.03, d = large) and CMJ (p < 0.01, d = large) than HIIT and CT. CT promoted greater benefits for fat, body mass loss and cardiorespiratory fitness than HIIT or RT modalities. This study provides important information for practitioners and therapists on the application of effective exercise regimes with obese youth to induce significant and beneficial body composition changes. The applied CT program and the respective programming parameters in terms of exercise intensity and volume can be used by practitioners as an effective exercise treatment to fight the pandemic overweight and obesity in youth.},
language = {en}
}
@article{TeichFuehnerBaehretal.2023,
author = {Teich, Paula and F{\"u}hner, Thea Heidi and Baehr, Florian and Puta, Christian and Granacher, Urs and Kliegl, Reinhold},
title = {Covid pandemic effects on the physical fitness of primary school children},
series = {Sports Medicine - Open},
volume = {9},
journal = {Sports Medicine - Open},
number = {1},
publisher = {Springer},
address = {New York},
issn = {2198-9761},
doi = {10.1186/s40798-023-00624-1},
pages = {19},
year = {2023},
abstract = {BackgroundIn spring of 2020, the Sars-CoV-2 incidence rate increased rapidly in Germany and around the world. Throughout the next 2 years, schools were temporarily closed and social distancing measures were put in place to slow the spread of the Covid-19 virus. Did these social restrictions and temporary school lockdowns affect children's physical fitness? The EMOTIKON project annually tests the physical fitness of all third-graders in the Federal State of Brandenburg, Germany. The tests assess cardiorespiratory endurance (6-min-run test), coordination (star-run test), speed (20-m sprint test), lower (powerLOW, standing long jump test), and upper (powerUP, ball-push test) limbs muscle power, and static balance (one-legged stance test with eyes closed). A total of 125,893 children were tested in the falls from 2016 to 2022. Primary analyses focused on 98,510 keyage third-graders (i.e., school enrollment according to the legal key date, aged 8 to 9 years) from 515 schools. Secondary analyses included 27,383 older-than-keyage third-graders (i.e., OTK, delayed school enrollment or repetition of a grade, aged 9 to 10 years), who have been shown to exhibit lower physical fitness than expected for their age. Linear mixed models fitted pre-pandemic quadratic secular trends, and took into account differences between children and schools.ResultsThird-graders exhibited lower cardiorespiratory endurance, coordination, speed and powerUP in the Covid pandemic cohorts (2020-2022) compared to the pre-pandemic cohorts (2016-2019). Children's powerLOW and static balance were higher in the pandemic cohorts compared to the pre-pandemic cohorts. From 2020 to 2021, coordination, powerLOW and powerUP further declined. Evidence for some post-pandemic physical fitness catch-up was restricted to powerUP. Cohen's |ds| for comparisons of the pandemic cohorts 2020-2022 with pre-pandemic cohorts 2016-2019 ranged from 0.02 for powerLOW to 0.15 for coordination. Within the pandemic cohorts, keyage children exhibited developmental losses ranging from approximately 1 month for speed to 5 months for cardiorespiratory endurance. For powerLOW and static balance, the positive pandemic effects translate to developmental gains of 1 and 7 months, respectively. Pre-pandemic secular trends may account for some of the observed differences between pandemic and pre-pandemic cohorts, especially in powerLOW, powerUP and static balance. The pandemic further increased developmental delays of OTK children in cardiorespiratory endurance, powerUP and balance.ConclusionsThe Covid-19 pandemic was associated with declines in several physical fitness components in German third-graders. Pandemic effects are still visible in 2022. Health-related interventions should specifically target those physical fitness components that were negatively affected by the pandemic (cardiorespiratory endurance, coordination, speed).},
language = {en}
}
@article{TeichFuehnerGranacheretal.2023,
author = {Teich, Paula and F{\"u}hner, Thea Heidi and Granacher, Urs and Kliegl, Reinhold},
title = {Physical fitness of primary school children differs depending on their timing of school enrollment},
series = {Scientific reports},
volume = {13},
journal = {Scientific reports},
number = {1},
publisher = {Springer Nature},
address = {London},
issn = {2045-2322},
doi = {10.1038/s41598-023-35727-y},
pages = {16},
year = {2023},
abstract = {Previous research has shown that children who were enrolled to school according to the legal key date (i.e., keyage children, between eight and nine years in third grade) exhibited a linear physical fitness development in the ninth year of life. In contrast, children who were enrolled with a delay (i.e., older-than-keyage children [OTK], between nine and ten years in third grade) exhibited a lower physical fitness compared to what would be expected for their age. In these studies, cross-sectional age differences within third grade and timing of school enrollment were confounded. The present study investigated the longitudinal development of keyage and OTK children from third to fifth grade. This design also afforded a comparison of the two groups at the same average chronological age, that is a dissociation of the effects of timing of school enrollment and age. We tested six physical fitness components: cardiorespiratory endurance, coordination, speed, power of lower and upper limbs, and static balance. 1502 children (i.e., 1206 keyage and 296 OTK children) from 35 schools were tested in third, fourth, and fifth grade. Except for cardiorespiratory endurance, both groups developed from third to fourth and from fourth to fifth grade and keyage children outperformed OTK children at the average ages of 9.5 or 10.5 years. For cardiorespiratory endurance, there was no significant gain from fourth to fifth grade and keyage and OTK children did not differ significantly at 10.5 years of age. One reason for a delayed school enrollment could be that a child is (or is perceived as) biologically younger than their chronological age at the school entry examination, implying a negative correlation between chronological and biological age for OTK children. Indeed, a simple reflection of chronological age brought the developmental rate of the chronologically youngest OTK children in line with the developmental rate observed for keyage children, but did not eliminate all differences. The mapping of chronological and biological age of OTK children and other possible reasons for lower physical fitness of OTK children remain a task for future research.},
language = {en}
}
@article{DelfanJuybariGorganiFiruzjaeeetal.2022,
author = {Delfan, Maryam and Juybari, Raheleh Amadeh and Gorgani-Firuzjaee, Sattar and H{\o}iriis Nielsen, Jens and Delfan, Neda and Laher, Ismail and Saeidi, Ayoub and Granacher, Urs and Zouhal, Hassane},
title = {High-intensity interval training improves cardiac function by miR-206 dependent HSP60 induction in diabetic rats},
series = {Frontiers in cardiovascular medicine},
volume = {9},
journal = {Frontiers in cardiovascular medicine},
publisher = {Frontiers Media},
address = {Lausanne},
issn = {2297-055X},
doi = {10.3389/fcvm.2022.927956},
pages = {11},
year = {2022},
abstract = {ObjectiveA role for microRNAs is implicated in several biological and pathological processes. We investigated the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on molecular markers of diabetic cardiomyopathy in rats. MethodsEighteen male Wistar rats (260 +/- 10 g; aged 8 weeks) with streptozotocin (STZ)-induced type 1 diabetes mellitus (55 mg/kg, IP) were randomly allocated to three groups: control, MICT, and HIIT. The two different training protocols were performed 5 days each week for 5 weeks. Cardiac performance (end-systolic and end-diastolic dimensions, ejection fraction), the expression of miR-206, HSP60, and markers of apoptosis (cleaved PARP and cytochrome C) were determined at the end of the exercise interventions. ResultsBoth exercise interventions (HIIT and MICT) decreased blood glucose levels and improved cardiac performance, with greater changes in the HIIT group (p < 0.001, eta(2): 0.909). While the expressions of miR-206 and apoptotic markers decreased in both training protocols (p < 0.001, eta(2): 0.967), HIIT caused greater reductions in apoptotic markers and produced a 20\% greater reduction in miR-206 compared with the MICT protocol (p < 0.001). Furthermore, both training protocols enhanced the expression of HSP60 (p < 0.001, eta(2): 0.976), with a nearly 50\% greater increase in the HIIT group compared with MICT. ConclusionsOur results indicate that both exercise protocols, HIIT and MICT, have the potential to reduce diabetic cardiomyopathy by modifying the expression of miR-206 and its downstream targets of apoptosis. It seems however that HIIT is even more effective than MICT to modulate these molecular markers.},
language = {en}
}
@article{SaidiZouhalBoullosaetal.2022,
author = {Saidi, Karim and Zouhal, Hassane and Boullosa, Daniel and Dupont, Gregory and Hackney, Anthony C. and Bideau, Benoit and Granacher, Urs and Ben Abderrahman, Abderraouf},
title = {Biochemical markers and wellness status during a congested match play period in elite soccer players},
series = {International journal of sports physiology and performance : IJSSP},
volume = {17},
journal = {International journal of sports physiology and performance : IJSSP},
number = {4},
publisher = {Human Kinetics Publ.},
address = {Champaign},
issn = {1555-0265},
doi = {10.1123/ijspp.2020-0914},
pages = {605 -- 620},
year = {2022},
abstract = {Objectives: To analyze biochemical markers, wellness status, and physical fitness in elite soccer players in relation to changes in training and match exposure during a congested period of match play. Methods: Fourteen elite soccer players were evaluated 3 times (T1, T2, and T3) over 12 weeks (T1-T2: 6-wk regular period of match play and T2-T3: 6-wk congested period of match play). Players performed vertical jump tests, repeated shuttle sprint ability test, and the Yo-Yo Intermittent Recovery Test at T1, T2, and T3. Plasma C-reactive protein, creatinine, and creatine kinase were analyzed at T1, T2, and T3. Wellness status was measured daily using the Hopper questionnaire (delayed onset of muscle soreness, stress, fatigue, and sleep quality). Training session rating of perceived exertion was also recorded on a daily basis. Results: A significant increase was found in stress, fatigue, delayed onset of muscle soreness scores, and Hopper index during the congested period (between T2 and T3) compared with the regular period (between T1 and T2) (.001 < P < .008, 0.8 < ES < 2.3). Between T2 and T3, significant relationships were found between the percentage variations (Delta\%) of C-reactive protein, and Delta\% of creatine kinase with the Hopper Index, and the Delta\% of fatigue score. In addition, the Delta\% of fatigue score and Delta\% of delayed onset of muscle soreness score correlated with Delta\% Yo-Yo Intermittent Recovery Test and Delta\% best of repeated shuttle sprint ability test (.49 < r < P < .01). Conclusions: An intensive period of congested match play significantly compromised elite soccer players' physical fitness and wellness status. Elite soccer players' wellness status reflects declines in physical fitness during this period while biochemical changes do not.},
language = {en}
}
@article{BrahmsHortobagyiKressigetal.2021,
author = {Brahms, Clemens Markus and Hortob{\´a}gyi, Tibor and Kressig, Reto W. and Granacher, Urs},
title = {The Interaction between mobility status and exercise specificity in older adults},
series = {Exercise and sport sciences reviews},
volume = {49},
journal = {Exercise and sport sciences reviews},
number = {1},
publisher = {Lippincott Williams \& Wilkins},
address = {Hagerstown, Md.},
issn = {0091-6331},
doi = {10.1249/JES.0000000000000237},
pages = {15 -- 22},
year = {2021},
abstract = {Many adults older than 60 yr experience mobility limitations. Although physical exercise improves older adults' mobility, differences in baseline mobility produce large variations in individual responses to interventions, and these responses could further vary by the type and dose of exercise. Here, we propose an exercise prescription model for older adults based on their current mobility status.},
language = {en}
}
@article{BehmAlizadehDruryetal.2021,
author = {Behm, David G. and Alizadeh, Shahab and Drury, Ben and Granacher, Urs and Moran, Jason},
title = {Non-local acute stretching effects on strength performance in healthy young adults},
series = {European journal of applied physiology},
volume = {121},
journal = {European journal of applied physiology},
number = {6},
publisher = {Springer},
address = {Berlin ; Heidelberg},
issn = {1439-6319},
doi = {10.1007/s00421-021-04657-w},
pages = {1517 -- 1529},
year = {2021},
abstract = {Background Static stretching (SS) can impair performance and increase range of motion of a non-exercised or non-stretched muscle, respectively. An underdeveloped research area is the effect of unilateral stretching on non-local force output. Objective The objective of this review was to describe the effects of unilateral SS on contralateral, non-stretched, muscle force and identify gaps in the literature. Methods A systematic literature search following preferred reporting items for systematic review and meta-analyses Protocols guidelines was performed according to prescribed inclusion and exclusion criteria. Weighted means and ranges highlighted the non-local force output response to unilateral stretching. The physiotherapy evidence database scale was used to assess study risk of bias and methodological quality. Results Unilateral stretching protocols from six studies involved 6.3 +/- 2 repetitions of 36.3 +/- 7.4 s with 19.3 +/- 5.7 s recovery between stretches. The mean stretch-induced force deficits exhibited small magnitude effect sizes for both the stretched (-6.7 +/- 7.1\%, d = -0.35: 0.01 to -1.8) and contralateral, non-stretched, muscles (-4.0 +/- 4.9\%, d = , 0.22: 0.08 to 1.1). Control measures exhibited trivial deficits. Conclusion The limited literature examining non-local effects of prolonged SS revealed that both the stretched and contralateral, non-stretched, limbs of young adults demonstrate small magnitude force deficits. However, the frequency of studies with these effects were similar with three measures demonstrating deficits, and four measures showing trivial changes. These results highlight the possible global (non-local) effects of prolonged SS. Further research should investigate effects of lower intensity stretching, upper versus lower body stretching, different age groups, incorporate full warm-ups, and identify predominant mechanisms among others.},
language = {en}
}
@article{HortobagyiDeakFarkasetal.2021,
author = {Hortobagyi, Tibor and Deak, Dorina and Farkas, Dora and Blenyesi, Eszter and Torok, Katalin and Granacher, Urs and Tollar, Jozsef},
title = {Effects of exercise dose and detraining duration on mobility at late midlife},
series = {Gerontology},
volume = {67},
journal = {Gerontology},
number = {4},
publisher = {Karger},
address = {Basel},
issn = {0304-324X},
doi = {10.1159/000513505},
pages = {403 -- 414},
year = {2021},
abstract = {Background: Office workers near retirement tend to be sedentary and can be prone to mobility limitations and diseases. We examined the dose effects of exergaming volume and duration of detraining on motor and cognitive function in office workers at late midlife to reduce sedentariness and mobility limitations. Methods: In an assessor-blinded randomized trial, 160 workers aged 55-65 years performed physically active video games in a nonimmersive form of virtual reality (exergaming) in small, supervised groups for 1 h, 1x, 2x, or 3x/week for 8 weeks followed by detraining for 8 and 16 weeks. Exergaming comprises high-intensity, full-body sensorimotor coordination, balance, endurance, and strengthening exercises. The primary outcome was the 6-minute walk test (6MWT), and secondary outcomes were body mass, self-reported physical activity, sleep quality, Berg Balance Scale, Short Physical Performance Battery, fast gait speed, dynamic balance, heart rate recovery after step test, and 6 cognitive tests. Results: The 3 groups were not different in any of the outcomes at baseline (all p > 0.05). The outcomes were stable and had acceptable reliability (intraclass correlation coefficients >= 0.334) over an 8-week control period. Training produced an inverted U-shaped dose response of no (1x), most (2x), and medium (3x/week) effects of exergaming volume in most motor and selected cognitive outcomes. The distance walked in the 6MWT (primary outcome) increased most (94 m, 19\%, p < 0.05), medium (57 m, 12\%, p < 0.05), and least (4 m, 1\%) after exergaming 2x, 3x, or 0x (control) (all different p < 0.05). The highest responders tended to retain the exercise effects over 8 weeks of detraining, independent of training volume. This maintenance effect was less consistent after 16 weeks of detraining. Conclusion: Less was more during training and lasted longer after detraining. A medium dose volume of exergaming produced the largest clinically meaningful improvements in mobility and selected cognitive tests in 60-year-old office workers with mild mobility limitations and intact cognition.},
language = {en}
}
@article{NegyesiHortobagyiHilletal.2022,
author = {Negyesi, Janos and Hortobagyi, Tibor and Hill, Jessica and Granacher, Urs and Nagatomi, Ryoichi},
title = {Can compression garments reduce the deleterious effects of physical exercise on muscle strength?},
series = {Sports medicine},
volume = {52},
journal = {Sports medicine},
number = {9},
publisher = {Springer},
address = {Northcote},
issn = {0112-1642},
doi = {10.1007/s40279-022-01681-4},
pages = {2159 -- 2175},
year = {2022},
abstract = {Background The use of compression garments (CGs) during or after training and competition has gained popularity in the last few decades. However, the data concerning CGs' beneficial effects on muscle strength-related outcomes after physical exercise remain inconclusive. Objective The aim was to determine whether wearing CGs during or after physical exercise would facilitate the recovery of muscle strength-related outcomes. Methods A systematic literature search was conducted across five databases (PubMed, SPORTDiscus, Web of Science, Scopus, and EBSCOhost). Data from 19 randomized controlled trials (RCTs) including 350 healthy participants were extracted and meta-analytically computed. Weighted between-study standardized mean differences (SMDs) with respect to their standard errors (SEs) were aggregated and corrected for sample size to compute overall SMDs. The type of physical exercise, the body area and timing of CG application, and the time interval between the end of the exercise and subsequent testing were assessed. Results CGs produced no strength-sparing effects (SMD [95\% confidence interval]) at the following time points (t) after physical exercise: immediately <= t < 24 h: - 0.02 (- 0.22 to 0.19), p = 0.87; 24 <= t < 48 h: - 0.00 (- 0.22 to 0.21), p = 0.98; 48 <= t < 72 h: - 0.03 (- 0.43 to 0.37), p = 0.87; 72 <= t < 96 h: 0.14 (- 0.21 to 0.49), p = 0.43; 96 h <= t: 0.26 (- 0.33 to 0.85), p = 0.38. The body area where the CG was applied had no strength-sparing effects. CGs revealed weak strength-sparing effects after plyometric exercise. Conclusion Meta-analytical evidence suggests that wearing a CG during or after training does not seem to facilitate the recovery of muscle strength following physical exercise. Practitioners, athletes, coaches, and trainers should reconsider the use of CG as a tool to reduce the effects of physical exercise on muscle strength.},
language = {en}
}
@article{SaeterbakkenStienAndersenetal.2022,
author = {Saeterbakken, Atle H. and Stien, Nicolay and Andersen, Vidar and Scott, Suzanne and Cumming, Kristoffer T. and Behm, David G. and Granacher, Urs and Prieske, Olaf},
title = {The effects of trunk muscle training on physical fitness and sport-specific performance in young and adult athletes},
series = {Sports medicine},
volume = {52},
journal = {Sports medicine},
number = {7},
publisher = {Springer},
address = {Northcote},
issn = {0112-1642},
doi = {10.1007/s40279-021-01637-0},
pages = {1599 -- 1622},
year = {2022},
abstract = {Background The role of trunk muscle training (TMT) for physical fitness (e.g., muscle power) and sport-specific performance measures (e.g., swimming time) in athletic populations has been extensively examined over the last decades. However, a recent systematic review and meta-analysis on the effects of TMT on measures of physical fitness and sport-specific performance in young and adult athletes is lacking. Objective To aggregate the effects of TMT on measures of physical fitness and sport-specific performance in young and adult athletes and identify potential subject-related moderator variables (e.g., age, sex, expertise level) and training-related programming parameters (e.g., frequency, study length, session duration, and number of training sessions) for TMT effects. Data Sources A systematic literature search was conducted with PubMed, Web of Science, and SPORTDiscus, with no date restrictions, up to June 2021. Study Eligibility Criteria Only controlled trials with baseline and follow-up measures were included if they examined the effects of TMT on at least one measure of physical fitness (e.g., maximal muscle strength, change-of-direction speed (CODS)/agility, linear sprint speed) and sport-specific performance (e.g., throwing velocity, swimming time) in young or adult competitive athletes at a regional, national, or international level. The expertise level was classified as either elite (competing at national and/or international level) or regional (i.e., recreational and sub-elite). Study Appraisal and Synthesis Methods The methodological quality of TMT studies was assessed using the Physiotherapy Evidence Database (PEDro) scale. A random-effects model was used to calculate weighted standardized mean differences (SMDs) between intervention and active control groups. Additionally, univariate sub-group analyses were independently computed for subject-related moderator variables and training-related programming parameters. Results Overall, 31 studies with 693 participants aged 11-37 years were eligible for inclusion. The methodological quality of the included studies was 5 on the PEDro scale. In terms of physical fitness, there were significant, small-to-large effects of TMT on maximal muscle strength (SMD = 0.39), local muscular endurance (SMD = 1.29), lower limb muscle power (SMD = 0.30), linear sprint speed (SMD = 0.66), and CODS/agility (SMD = 0.70). Furthermore, a significant and moderate TMT effect was found for sport-specific performance (SMD = 0.64). Univariate sub-group analyses for subject-related moderator variables revealed significant effects of age on CODS/agility (p = 0.04), with significantly large effects for children (SMD = 1.53, p = 0.002). Further, there was a significant effect of number of training sessions on muscle power and linear sprint speed (p <= 0.03), with significant, small-to-large effects of TMT for > 18 sessions compared to <= 18 sessions (0.45 <= SMD <= 0.84, p <= 0.003). Additionally, session duration significantly modulated TMT effects on linear sprint speed, CODS/agility, and sport-specific performance (p <= 0.05). TMT with session durations <= 30 min resulted in significant, large effects on linear sprint speed and CODS/agility (1.66 <= SMD <= 2.42, p <= 0.002), whereas session durations > 30 min resulted in significant, large effects on sport-specific performance (SMD = 1.22, p = 0.008). Conclusions Our findings indicate that TMT is an effective means to improve selected measures of physical fitness and sport-specific performance in young and adult athletes.
Independent sub-group analyses suggest that TMT has the potential to improve CODS/agility, but only in children. Additionally, more (> 18) and/or shorter duration (<= 30 min) TMT sessions appear to be more effective for improving lower limb muscle power, linear sprint speed, and CODS/agility in young or adult competitive athletes.},
language = {en}
}
@article{HaileFuehnerGranacheretal.2021,
author = {Haile, Sarah R. and F{\"u}hner, Thea Heidi and Granacher, Urs and Stocker, Julien and Radtke, Thomas and Kriemler, Susi},
title = {Reference values and validation of the 1-minute sit-to-stand test in healthy 5-16-year-old youth},
series = {BMJ open},
volume = {11},
journal = {BMJ open},
number = {5},
publisher = {BMJ Publishing Group},
address = {London},
issn = {2044-6055},
doi = {10.1136/bmjopen-2021-049143},
pages = {7},
year = {2021},
abstract = {Objectives: It is essential to have simple, reliable and valid tests to measure children's functional capacity in schools or medical practice. The 1-minute sit-to-stand (STS) test is a quick fitness test requiring little equipment or space that is increasingly used in both healthy populations and those with chronic disease. We aimed to provide age-specific and sex-specific reference values of STS test in healthy children and adolescents and to evaluate its short-term reliability and construct validity. Design setting and participants: Cross-sectional convenience sample from six public schools and one science fair in central Europe. Overall, 587 healthy participants aged 5-16 years were recruited and divided into age groups of 3 years each. Outcomes: 1-minute STS. To evaluate short-term reliability, some children performed the STS test twice. To evaluate construct validity, some children also performed a standing long jump (SLJ) and a maximal incremental exercise test. Results: Data from 547 youth aged 5-16 years were finally included in the analyses. The median number of repetitions in 1 min in males (females) ranged from 55 [95\% CI: 38 to 72] (53 [95\% CI: 35 to 76]) in 14-16-year olds to 59 [95\% CI: 41 to 77] (60 [95\% CI: 38 to 77]) in 8-10-year olds. Children who repeated STS showed a learning effect of on average 4.8 repetitions more than the first test (95\% limits of agreement: -6.7 to 16.4). Moderate correlations were observed between the STS and the SLJ (r=0.48) tests and the maximal exercise test (r=0.43). Conclusions: The reported STS reference values can be used to interpret STS test performance in children and adolescents. The STS appears to have good test- retest reliability, but a learning effect of about 10\%. The association of STS with other measures of physical fitness should be further explored in a larger study and technical standards for its conduct are needed.},
language = {en}
}
@article{JafarnezhadgeroGhorbanlooFatollahietal.2021,
author = {Jafarnezhadgero, AmirAli and Ghorbanloo, Farshad and Fatollahi, Amir and Dionisio, Valdeci Carlos and Granacher, Urs},
title = {Effects of an elastic resistance band exercise program on kinetics and muscle activities during walking in young adults with genu valgus},
series = {Clinical biomechanics : a journal affiliated to the International Society of Biomechanics and the American Society of Biomechanics},
volume = {81},
journal = {Clinical biomechanics : a journal affiliated to the International Society of Biomechanics and the American Society of Biomechanics},
publisher = {Elsevier Science},
address = {Amsterdam [u.a.]},
issn = {0268-0033},
doi = {10.1016/j.clinbiomech.2020.105215},
pages = {10},
year = {2021},
abstract = {Background: This double-blinded randomized-controlled-trial aimed to identify the effects of an elastic band resistance training on walking kinetics and muscle activities in young adults with genu valgus. Methods: Forty-two male young adults aged 22.5(2.7) years with genu valgus were randomly allocated to two experimental groups. The intervention group (n = 21) conducted a 14-weeks elastic band resistance training. The control group was passive during the intervention period and received the same treatment after the post-tests. Pre and post training, ground reaction forces and lower limb muscle activities were recorded during walking. Findings: Results revealed significant group-by-time interactions for peak medial ground reaction force and timeto-peak for posterior ground reaction force in favor of the intervention group (p < 0.012; d = 0.83-3.76). Resistance training with elastic bands resulted in significantly larger peak medial ground reaction force (p < 0.001; d = 1.45) and longer time-to-peak for posterior ground reaction force (p < 0.001; d = 1.85). Finding showed significant group-by-time interactions for peak positive free moment amplitudes in favor of the intervention group (p < 0.001; d = 1.18-2.02). Resistance training resulted in a lower peak positive free moment amplitude (p = 0.001; d = 1.46). With regards to muscle activities, the analysis revealed significant group-by time interactions for rectus femoris and gluteus medius activities during the push-off phase in favor of the intervention group (p < 0.038; d = 0.68-0.89). Resistance training induced higher rectus femoris (p = 0.038; d = 0.84) and gluteus medius (p = 0.007; d = 0.54) activities. Interpretation: This study proved the effectiveness of resistance training using elastic bands on kinetics and muscle activities during walking in male adults with genu valgus disorder. Given that this training regime is low cost, effective, and easy-to-administer, we suggest that it should be implemented as a rehabilitative or preventive means for young adults with genu valgus.},
language = {en}
}
@article{WickKriemlerGranacher2021,
author = {Wick, Kristin and Kriemler, Susi and Granacher, Urs},
title = {Effects of a strength-dominated exercise program on physical fitness and cognitive performance in preschool children},
series = {Journal of strength and conditioning research : the research journal of the NSCA},
volume = {35},
journal = {Journal of strength and conditioning research : the research journal of the NSCA},
number = {4},
publisher = {Lippincott Williams \& Wilkins},
address = {Philadelphia},
issn = {1064-8011},
doi = {10.1519/JSC.0000000000003942},
pages = {983 -- 990},
year = {2021},
abstract = {Wick, K, Kriemler, S, and Granacher, U. Effects of a strength-dominated exercise program on physical fitness and cognitive performance in preschool children. J Strength Cond Res 35(4): 983-990, 2021-Childhood is characterized by high neuroplasticity that affords qualitative rather than quantitative components of physical activity to maximize the potential to sufficiently develop motor skills and foster long-term engagement in regular physical activity. This study examined the effects of an integrative strength-dominated exercise program on measures of physical fitness and cognitive performance in preschool children. Children aged 4-6 years from 3 kindergartens were randomized into an intervention (INT) group (n = 32) or a control group (n = 22). The 10-week intervention period was conducted 3 times per week (each session lasted 30 minutes) and included exercises for the promotion of muscle strength and power, coordination, and balance. Pre and post training, tests were conducted for the assessment of muscle strength (i.e., handgrip strength), muscle power (i.e., standing long jump), balance (i.e., timed single-leg stand), coordination (hopping on right/left leg), and attentional span (i.e., "Konzentrations-Handlungsverfahren fur Vorschulkinder" [concentration-action procedure for preschoolers]). Results from 2 x 2 repeated-measures analysis of covariance revealed a significant (p <= 0.05) and near significant (p = 0.051) group x time interaction for the standing long jump test and the Konzentrations-Handlungsverfahren. Post hoc tests showed significant pre-post changes for the INT (p < 0.001; d = 1.53) but not the CON (p = 0.72; d = 0.83). Our results indicate that a 10-week strength-dominated exercise program increased jump performance with a concomitant trend toward improvements in attentional capacity of preschool children. Thus, we recommend implementing this type of exercise program for preschoolers.},
language = {en}
}
@article{ChaabeneNegraMoranetal.2021,
author = {Chaabene, Helmi and Negra, Yassine and Moran, Jason and Prieske, Olaf and Sammoud, Senda and Ramirez-Campillo, Rodrigo and Granacher, Urs},
title = {Plyometric training improves not only measures of linear speed, power, and change-of-direction speed but also repeated sprint ability in young female handball players},
series = {Journal of strength and conditioning research : the research journal of the NSCA},
volume = {35},
journal = {Journal of strength and conditioning research : the research journal of the NSCA},
number = {8},
publisher = {Lippincott Williams \& Wilkins},
address = {Philadelphia},
issn = {1064-8011},
doi = {10.1519/JSC.0000000000003128},
pages = {2230 -- 2235},
year = {2021},
abstract = {This study examined the effects of an 8-week plyometric training (PT) program on components of physical fitness in young female handball players. Twenty-one female adolescent handball players were assigned to an experimental group (EG, n = 12; age = 15.9 +/- 0.2 years) or an active control group (CG, n = 9, age = 15.9 +/- 0.3 years). While EG performed plyometric exercises in replacement of some handball-specific drills, CG maintained the regular training schedule. Baseline and follow-up tests were performed for the assessment of linear speed (i.e., 5-, 10-, and 20-m time), change-of-direction (CoD) speed (i.e., T-test time), muscle power (i.e., countermovement jump [CMJ] height and reactive strength index [RSI]), and repeated sprint ability (RSA) (RSA total time [RSA(total)], RSA best time [RSA(best)], and RSA fatigue index [RSA(FI)]). Data were analyzed using magnitude-based inferences. Within-group analyses for the EG revealed moderate-to-large improvements for the 5-m (effect size [ES] = 0.81 [0.1-1.5]), 10-m sprint time (ES = 0.84 [0.1-1.5]), RSI (ES = 0.75 [0.1-1.4]), RSA(FI) (ES = 0.65 [0.0-1.3]), and T-test time (ES = 1.46 [0.7-2.2]). Trivial-to-small ES was observed for RSA(best) (ES = 0.18 [-0.5 to 0.9]), RSA(total) (ES = 0.45 [-0.2 to 1.1]), 20-m sprint time (ES = 0.56 [-0.1 to 1.2]), and CMJ height (ES = 0.57 [-0.1 to 1.3]). For the CG, within-group analyses showed a moderate performance decline for T-test time (ES = -0.71 [-1.5 to 0.1]), small decreases for 5-m sprint time (ES = -0.46 [-1.2 to 0.3]), and a trivial decline for 10-m (ES = -0.10 [-0.9 to 0.7]) and 20-m sprint times (ES = -0.16 [-0.9 to 0.6]), RSA(total) (ES = 0.0 [-0.8 to 0.8]), and RSA(best) (ES = -0.20 [-0.9 to 0.6]). The control group achieved trivial-to-small improvements for CMJ height (ES = 0.10 [-0.68 to 0.87]) and RSI (ES = 0.30 [-0.5 to 1.1]). In conclusion, a short-term in-season PT program, in replacement of handball-specific drills, is effective in improving measures of physical fitness (i.e., linear/CoD speed, jumping, and RSA) in young female handball players.},
language = {en}
}
@article{JafarnezhadgeroNorooziFakhrietal.2022,
author = {Jafarnezhadgero, Amir Ali and Noroozi, Raha and Fakhri, Ehsan and Granacher, Urs and Oliveira, Anderson Souza},
title = {The Impact of COVID-19 and muscle fatigue on cardiorespiratory fitness and running kinetics in female recreational runners},
series = {Frontiers in physiology},
volume = {13},
journal = {Frontiers in physiology},
publisher = {Frontiers Media},
address = {Lausanne},
issn = {1664-042X},
doi = {10.3389/fphys.2022.942589},
pages = {10},
year = {2022},
abstract = {Background: There is evidence that fully recovered COVID-19 patients usually resume physical exercise, but do not perform at the same intensity level performed prior to infection. The aim of this study was to evaluate the impact of COVID-19 infection and recovery as well as muscle fatigue on cardiorespiratory fitness and running biomechanics in female recreational runners. Methods: Twenty-eight females were divided into a group of hospitalized and recovered COVID-19 patients (COV, n = 14, at least 14 days following recovery) and a group of healthy age-matched controls (CTR, n = 14). Ground reaction forces from stepping on a force plate while barefoot overground running at 3.3 m/s was measured before and after a fatiguing protocol. The fatigue protocol consisted of incrementally increasing running speed until reaching a score of 13 on the 6-20 Borg scale, followed by steady-state running until exhaustion. The effects of group and fatigue were assessed for steady-state running duration, steady-state running speed, ground contact time, vertical instantaneous loading rate and peak propulsion force. Results: COV runners completed only 56\% of the running time achieved by the CTR (p < 0.0001), and at a 26\% slower steady-state running speed (p < 0.0001). There were fatigue-related reductions in loading rate (p = 0.004) without group differences. Increased ground contact time (p = 0.002) and reduced peak propulsion force (p = 0.005) were found for COV when compared to CTR. Conclusion: Our results suggest that female runners who recovered from COVID-19 showed compromised running endurance and altered running kinetics in the form of longer stance periods and weaker propulsion forces. More research is needed in this area using larger sample sizes to confirm our study findings.},
language = {en}
}
@article{HortobagyiVetrovskyBalbimetal.2022,
author = {Hortob{\´a}gyi, Tibor and Vetrovsky, Tomas and Balbim, Guilherme Moraes and Sorte Silva, Narlon Cassio Boa and Manca, Andrea and Deriu, Franca and Kolmos, Mia and Kruuse, Christina and Liu-Ambrose, Teresa and Radak, Zsolt and Vaczi, Mark and Johansson, Hanna and Rocha dos Santos, Paulo Cezar and Franzen, Erika and Granacher, Urs},
title = {The impact of aerobic and resistance training intensity on markers of neuroplasticity in health and disease},
series = {Ageing research reviews : ARR},
volume = {80},
journal = {Ageing research reviews : ARR},
publisher = {Elsevier},
address = {Clare},
issn = {1568-1637},
doi = {10.1016/j.arr.2022.101698},
pages = {18},
year = {2022},
abstract = {Objective: To determine the effects of low- vs. high-intensity aerobic and resistance training on motor and cognitive function, brain activation, brain structure, and neurochemical markers of neuroplasticity and the association thereof in healthy young and older adults and in patients with multiple sclerosis, Parkinson's disease, and stroke. Design: Systematic review and robust variance estimation meta-analysis with meta-regression. Data sources: Systematic search of MEDLINE, Web of Science, and CINAHL databases. Results: Fifty studies with 60 intervention arms and 2283 in-analyses participants were included. Due to the low number of studies, the three patient groups were combined and analyzed as a single group. Overall, low- (g=0.19, p = 0.024) and high-intensity exercise (g=0.40, p = 0.001) improved neuroplasticity. Exercise intensity scaled with neuroplasticity only in healthy young adults but not in healthy older adults or patient groups. Exercise-induced improvements in neuroplasticity were associated with changes in motor but not cognitive outcomes. Conclusion: Exercise intensity is an important variable to dose and individualize the exercise stimulus for healthy young individuals but not necessarily for healthy older adults and neurological patients. This conclusion warrants caution because studies are needed that directly compare the effects of low- vs. high-intensity exercise on neuroplasticity to determine if such changes are mechanistically and incrementally linked to improved cognition and motor function.},
language = {en}
}
@article{AhmadiHeratAlizadehetal.2021,
author = {Ahmadi, Hamid and Herat, Nehara and Alizadeh, Shahab and Button, Duane C. and Granacher, Urs and Behm, David G.},
title = {Effect of an inverted seated position with upper arm blood flow restriction on measures of elbow flexors neuromuscular performance},
series = {PLOS ONE / Public Library of Science},
volume = {16},
journal = {PLOS ONE / Public Library of Science},
number = {5},
publisher = {PLoS},
address = {San Fransisco},
issn = {1932-6203},
doi = {10.1371/journal.pone.0245311},
pages = {19},
year = {2021},
abstract = {Purpose The objective of the investigation was to determine the concomitant effects of upper arm blood flow restriction (BFR) and inversion on elbow flexors neuromuscular responses. Methods Randomly allocated, 13 volunteers performed four conditions in a within-subject design: rest (control, 1-min upright position without BFR), control (1-min upright with BFR), 1-min inverted (without BFR), and 1-min inverted with BFR. Evoked and voluntary contractile properties, before, during and after a 30-s maximum voluntary contraction (MVC) exercise intervention were examined as well as pain scale. Results Inversion induced significant pre-exercise intervention decreases in elbow flexors MVC (21.1\%, Z2p = 0.48, p = 0.02) and resting evoked twitch forces (29.4\%, Z2p = 0.34, p = 0.03). The 30-s MVC induced significantly greater pre- to post-test decreases in potentiated twitch force (Z2p = 0.61, p = 0.0009) during inversion (75\%) than upright (65.3\%) conditions. Overall, BFR decreased MVC force 4.8\% (Z2p = 0.37, p = 0.05). For upright position, BFR induced 21.0\% reductions in M-wave amplitude (Z2p = 0.44, p = 0.04). There were no significant differences for electromyographic activity or voluntary activation as measured with the interpolated twitch technique. For all conditions, there was a significant increase in pain scale between the 40-60 s intervals and post-30-s MVC (upright< inversion, and without BFR< BFR). Conclusion The concomitant application of inversion with elbow flexors BFR only amplified neuromuscular performance impairments to a small degree. Individuals who execute forceful contractions when inverted or with BFR should be cognizant that force output may be impaired.},
language = {en}
}
@article{NegraChaabeneFernandezFernandezetal.2020,
author = {Negra, Yassine and Chaabene, Helmi and Fernandez-Fernandez, Jaime and Sammoud, Senda and Bouguezzi, Raja and Prieske, Olaf and Granacher, Urs},
title = {Short-term plyometric Jump training improves repeated-sprint ability in prepuberal male soccer players},
series = {Journal of strength and conditioning research : the research journal of the NSCA},
volume = {34},
journal = {Journal of strength and conditioning research : the research journal of the NSCA},
number = {11},
publisher = {Lippincott Williams \& Wilkins},
address = {Philadelphia},
issn = {1064-8011},
doi = {10.1519/JSC.0000000000002703},
pages = {3241 -- 3249},
year = {2020},
abstract = {This study examined the effects of a short-term (i.e., 8 weeks) combined horizontal and vertical plyometric jump training (PJT) program in combination with regular soccer-specific training as compared with soccer-specific training only on jump and change of direction (CoD) performances, speed, and repeated-sprint ability (RSA) in prepuberal male soccer players. Twenty-four players were recruited and randomly assigned to either a PJT group (PJT(G); n = 13; 12.7 +/- 0.2 years) or an active control group (CONG; n = 11; 12.7 +/- 0.2 years). The outcome measures included tests for the assessment of jump performance (drop jump from 20- to 40-cm height [DJ20 and DJ40] and 3-hop test [THT]), speed (20-m sprint), CoD (T-test), and RSA (20-m repeated shuttle sprint). Data were analyzed using magnitude-based inferences. Within-group analyses revealed large performance improvements in the T-test (d = -1.2), DJ20 (d = 3.7), DJ40 (d = 3.6), THT (d = 0.6), and the RSA(total) (d = -1.6) in the PJT(G). Between-group analyses showed greater performance improvements in the T-test (d = -2.9), 20-m sprint time (d = -2.0), DJ20 (d = 2.4), DJ40 (d = 2.0), THT (d = 1.9), RSA(best) (d = -1.9), and the RSA(total) (d = -1.9) in the PJT(G) compared with CONG. Eight weeks of an in-season PJT in addition to regular soccer-specific training induced larger increases in measures of physical fitness in prepuberal male soccer players compared with regular soccer-specific training only. More specifically, PJT was effective in improving RSA performance.},
language = {en}
}
@article{SinghKushwahSinghetal.2022,
author = {Singh, Gaurav and Kushwah, Gaurav Singh and Singh, Tanvi and Thapa, Rohit Kumar and Granacher, Urs and Ramirez-Campillo, Rodrigo},
title = {Effects of sand-based plyometric-jump training in combination with endurance running on outdoor or treadmill surface on physical fitness in young adult males},
series = {Journal of sports science \& medicine},
volume = {21},
journal = {Journal of sports science \& medicine},
number = {2},
publisher = {Department of Sports Medicine, Medical Faculty of Uludag University},
address = {Bursa},
issn = {1303-2968},
doi = {10.52082/jssm.2022.277},
pages = {277 -- 286},
year = {2022},
abstract = {This study aimed at examining the effects of nine weeks of sand-based plyometric jump training (PJT) combined with endurance running on either outdoor or treadmill surface on measures of physical fitness. Male participants (age, 20.1 +/- 1.7 years) were randomly assigned to a sand-based PJT combined with endurance running on outdoor surface (OT, n = 25) or treadmill surface (TT, n = 25). The endurance miming intervention comprised a mixed training method, i.e., long slow distance, tempo, and interval running drills. A control group was additionally included in this study (CG, n = 25). Participants in CG followed their regular physical activity as OT and TT but did not receive any specific intervention. Individuals were assessed for their 50-m linear sprint time, standing long jump (SLJ) distance, cardiorespiratory fitness (i.e., Cooper test), forced vital capacity (FVC), calf girth, and resting heart rate (RHR). A three (groups: OT, TT, CG) by two (time: pre, post) ANOVA for repeated measures was used to analyze the exercise-specific effects. In case of significant group-by-time interactions, Bonferroni adjusted paired (within-group) and independent (between-group comparisons at post) t-tests were used for post-hoc analyses. Significant group-by-time interactions were found for all dependent variables (p < 0.001 - 0.002, eta(2)(p) = 0.16 - 0.78). Group-specific post-hoc tests showed improvements for all variables after OT (p < 0.001, Hedges'g effect size [g] = 0.05 - 1.94) and TT (p < 0.001, g = 0.04 - 2.73), but not in the CG (p = 0.058 - 1.000, g = 0.00 - 0.34). Compared to CG, OT showed larger SLJ (p = 0.001), cardiorespiratory fitness (p = 0.004), FVC (p = 0.008), and RHR (p < 0.001) improvements. TT showed larger improvements in SLJ (p = 0.036), cardiorespiratory fitness (p < 0.001), and RHR (p < 0.001) compared with CG. Compared to OT, TT showed larger improvements for SLJ (p = 0.018). In conclusion, sand-based PJT combined with either OT or TT similarly improved most measures of physical fitness, with greater SLJ improvement after TT. Coaches may use both concurrent exercise regimes based on preferences and logistical constrains (e.g., weather; access to treadmill equipment).},
language = {en}
}
@article{PrieskeChaabeneKullmannetal.2022,
author = {Prieske, Olaf and Chaabene, Helmi and Kullmann, Niclas and Granacher, Urs},
title = {Effects of Individualized Versus Traditional Power Training on Strength, Power, Jump Performances, and Body Composition in Young Male Nordic Athletes},
series = {International journal of sports physiology and performance},
volume = {17},
journal = {International journal of sports physiology and performance},
number = {4},
publisher = {Human Kinetics Publ.},
address = {Champaign},
issn = {1555-0265},
doi = {10.1123/ijspp.2021-0074},
pages = {541 -- 548},
year = {2022},
abstract = {Purpose: This study aimed to examine the effects of individualized-load power training (IPT) versus traditional moderate-load power training (TPT) on strength, power, jump performance, and body composition in elite young Nordic athletes. Methods: In a randomized crossover design, 10 young male athletes (ski jumpers, Nordic combined athletes) age 17.5 (0.6) years (biological maturity status: +3.5 y postpeak height velocity) who competed on a national or international level performed 5 weeks of IPT (4 x 5 repetitions at 49\%-72\% 1-repetiton maximum [RM]) and TPT (5 x 5 repetitions at 50\%-60\% 1-RM) in addition to their regular training. Testing before, between, and after both training blocks comprised the assessment of muscle strength (loaded back squat 3-RM), power (maximal loaded back squat power), jump performance (eg, drop-jump height, reactive strength index), and body composition (eg, skeletal muscle mass). Results: Significant, large-size main effects for time were found for muscle strength (P < .01; g = 2.7), reactive strength index (P = .03; g= 1.6), and drop jump height (P = .02; g= 1.9) irrespective of the training condition (IPT, TPT). No significant time-by-condition interactions were observed. For measures of body composition, no significant main effects of condition and time or time-by-condition interactions were found. Conclusions: Our findings demonstrate that short-term IPT and TPT at moderate loads in addition to regular training were equally effective in improving measures of muscle strength (loaded back squat 3-RM) and vertical jump performance (reactive strength index, drop jump, and height) in young Nordic athletes.},
language = {en}
}
@article{JafarnezhadgeroPiranHamlabadiSajedietal.2022,
author = {Jafarnezhadgero, Amir Ali and Piran Hamlabadi, Milad and Sajedi, Heidar and Granacher, Urs},
title = {Recreational runners who recovered from COVID-19 show different running kinetics and muscle activities compared with healthy controls},
series = {Gait \& posture : official journal of Gait and Clinical Movement Analysis Society, European Society of Movement Analysis in Adults and Children, Societ{\`a} Italiana di Analisi del Movimento in Clinica, International Society for Posture and Gait Research},
volume = {91},
journal = {Gait \& posture : official journal of Gait and Clinical Movement Analysis Society, European Society of Movement Analysis in Adults and Children, Societ{\`a} Italiana di Analisi del Movimento in Clinica, International Society for Posture and Gait Research},
publisher = {Elsevier},
address = {Amsterdam [u.a.]},
issn = {0966-6362},
doi = {10.1016/j.gaitpost.2021.11.002},
pages = {260 -- 265},
year = {2022},
abstract = {Background: Social isolation through quarantine represents an effective means to prevent COVID-19 infection. A negative side-effect of quarantine is low physical activity. Research question: What are the differences of running kinetics and muscle activities of recreational runners with a history of COVID-19 versus healthy controls? Methods: Forty men and women aged 20-30 years participated in this study and were divided into two experimental groups. Group 1 (age: 24.1 +/- 2.9) consisted of participants with a history of COVID-19 (COVID group) and group 2 (age: 24.2 +/- 2.7) of healthy age and sex-matched controls (controls). Both groups were tested for their running kinetics using a force plate and electromyographic activities (i.e., tibialis anterior [TA], gastrocnemius medialis [Gas-M], biceps femoris [BF], semitendinosus [ST], vastus lateralis [VL], vastus medialis [VM], rectus femoris [RF], gluteus medius [Glut-M]). Results: Results demonstrated higher peak vertical (p = 0.029; d=0.788) and medial (p = 0.004; d=1.119) ground reaction forces (GRFs) during push-off in COVID individuals compared with controls. Moreover, higher peak lateral GRFs were found during heel contact (p = 0.001; d=1.536) in the COVID group. COVID-19 individuals showed a shorter time-to-reach the peak vertical (p = 0.001; d=3.779) and posterior GRFs (p = 0.005; d=1.099) during heel contact. Moreover, the COVID group showed higher Gas-M (p = 0.007; d=1.109) and lower VM activity (p = 0.026; d=0.811) at heel contact. Significance: Different running kinetics and muscle activities were found in COVID-19 individuals versus healthy controls. Therefore, practitioners and therapists are advised to implement balance and/or strength training to improve lower limbs alignment and mediolateral control during dynamic movements in runners who recovered from COVID-19.},
language = {en}
}
@article{WickKriemlerGranacher2022,
author = {Wick, Kristin and Kriemler, Susi and Granacher, Urs},
title = {Associations between measures of physical fitness and cognitive performance in preschool children},
series = {BMC sports science, medicine \& rehabilitation},
volume = {14},
journal = {BMC sports science, medicine \& rehabilitation},
number = {1},
publisher = {BMC},
address = {London},
issn = {2052-1847},
doi = {10.1186/s13102-022-00470-w},
pages = {8},
year = {2022},
abstract = {Background: Given that recent studies report negative secular declines in physical fitness, associations between fitness and cognition in childhood are strongly discussed. The preschool age is characterized by high neuroplasticity which effects motor skill learning, physical fitness, and cognitive development. The aim of this study was to assess the relation of physical fitness and attention (including its individual dimensions (quantitative, qualitative)) as one domain of cognitive performance in preschool children. We hypothesized that fitness components which need precise coordination compared to simple fitness components are stronger related to attention. Methods: Physical fitness components like static balance (i.e., single-leg stance), muscle strength (i.e., handgrip strength), muscle power (i.e., standing long jump), and coordination (i.e., hopping on one leg) were assessed in 61 healthy children (mean age 4.5 +/- 0.6 years; girls n = 30). Attention was measured with the "Konzentrations-Handlungsverfahren fur Vorschulkinder" [concentration-action procedure for preschoolers]). Analyses were adjusted for age, body height, and body mass. Results: Results from single linear regression analysis revealed a significant (p < 0.05) association between physical fitness (composite score) and attention (composite score) (standardized ss = 0.40), showing a small to medium effect (F-2 = 0.14). Further, coordination had a significant relation with the composite score and the quantitative dimension of attention (standardized ss = 0.35; p < 0.01; standardized ss = - 0.33; p < 0.05). Coordination explained about 11\% (composite score) and 9\% (quantitative dimension) of the variance in the stepwise multiple regression model. Conclusion: The results indicate that performance in physical fitness, particularly coordination, is related to attention in preschool children. Thus, high performance in complex fitness components (i.e., hopping on one leg) tends to predict attention in preschool children. Further longitudinal studies should focus on the effectiveness of physical activity programs implementing coordination and complex exercises at preschool age to examine cause-effect relationships between physical fitness and attention precisely.},
language = {en}
}
@article{PrieskeDalagerLooksetal.2021,
author = {Prieske, Olaf and Dalager, Tina and Looks, Vanessa and Golle, Kathleen and Granacher, Urs},
title = {Physical fitness and psycho-cognitive performance in the young and middle-aged workforce with primarily physical versus mental work demands},
series = {Journal of public health : from theory to practice : official organ of the Deutscher Verband f{\"u}r Gesundheitswissenschaften Public Health e.V. (DVGPH)},
volume = {29},
journal = {Journal of public health : from theory to practice : official organ of the Deutscher Verband f{\"u}r Gesundheitswissenschaften Public Health e.V. (DVGPH)},
number = {1},
publisher = {Springer},
address = {Berlin ; Heidelberg},
issn = {2198-1833},
doi = {10.1007/s10389-019-01099-9},
pages = {75 -- 84},
year = {2021},
abstract = {Aim The purpose of this study was to examine physical fitness and psycho-cognitive performance and their associations in young and middle-aged workers with primarily physical versus mental work demands. Subjects and methods Healthy young and middle-aged workers (73 men, age = 33 +/- 7 years; 75 women, age = 35 +/- 9 years) were recruited from German small-to-medium-sized enterprises (< 250 employees) and classified into groups with primarily mental (MD) or physical demands (PD) at work. Participants were tested for cardiorespiratory fitness, trunk flexor/extensor muscular endurance, handgrip strength, balance, leg muscle power, perceived stress, cognitive performance, and work ability. Results Ninety-four workers were allocated to the MD (53\% females) and 54 to the PD (46\% females) groups. The MD group showed significantly better balance, trunk extensor muscular endurance, and cognitive performance (p < 0.035, 0.35 <= d <= 0.55) and less stress compared with the PD group (p < 0.023, d = 0.38). Group-specific Spearman rank correlation analysis (r(S)) revealed significant small-to-medium-sized correlations between physical fitness and cognitive performance (- 0.205 <= r(S) <= 0.434) in the MD and PD groups. Significant small-to-medium-sized correlations were found for physical fitness and stress/work ability (0.211 <= r(S) <= 0.301) in the MD group only. Further, associations of trunk extensor muscular endurance and work ability were significantly higher in the MD group (r(S) = 0.240) compared with the PD group (r(S) = - 0.141; z = 2.16, p = 0.031). Conclusions MD workers showed better physical fitness measures (balance, trunk extensor muscular endurance) and cognitive performance and lower levels of perceived stress compared with PD workers. Small-to-medium-sized associations between physical fitness and psycho-cognitive performance measures indicate that gains in physical fitness may at least partly contribute to psycho-cognitive performance and/or vice versa, particularly in MD workers.},
language = {en}
}
@article{PrieskeChaabeneGaebleretal.2020,
author = {Prieske, Olaf and Chaabene, Helmi and G{\"a}bler, Martijn and Herz, Michael and Helm, Norman and Markov, Adrian and Granacher, Urs},
title = {Seasonal changes in anthropometry, body composition, and physical fitness and the relationships with sporting success in young sub-elite judo athletes},
series = {International journal of environmental research and public health : IJERPH},
volume = {17},
journal = {International journal of environmental research and public health : IJERPH},
number = {19},
publisher = {MDPI AG},
address = {Basel},
issn = {1660-4601},
doi = {10.3390/ijerph17197169},
pages = {17},
year = {2020},
abstract = {This exploratory study aimed to monitor long-term seasonal developments in measures of anthropometry, body composition, and physical fitness in young judo athletes, and to compute associations between these measures and sporting success. Forty-four young judoka (20 females, 24 males) volunteered to participate. Tests for the assessment of anthropometry (e.g., body height/mass), body-composition (e.g., lean body mass), muscle strength (isometric handgrip strength), vertical jumping (e.g., countermovement-jump (CMJ) height), and dynamic balance (Y-balance test) were conducted at the beginning and end of a 10-month training season. Additionally, sporting success at the end of the season was recorded for each athlete. Analyses revealed significant time x sex interaction effects for lean-body-mass, isometric handgrip strength, and CMJ height (0.7 <= d <= 1.6). Post-hoc analyses showed larger gains for all measures in young males (1.9 <= d <= 6.0) compared with females (d = 2.4) across the season. Additionally, significant increases in body height and mass as well as Y-balance test scores were found from pre-to-post-test (1.2 <= d <= 4.3), irrespective of sex. Further, non-significant small-to-moderate-sized correlations were identified between changes in anthropometry/body composition/physical fitness and sporting success (p > 0.05; -0.34 <= rho <= 0.32). Regression analysis confirmed that no model significantly predicted sporting success. Ten months of judo training and/or growth/maturation contributed to significant changes in anthropometry, body composition, and physical fitness, particularly in young male judo athletes.},
language = {en}
}
@article{NegraChaabeneSammoudetal.2020,
author = {Negra, Yassine and Chaabene, Helmi and Sammoud, Senda and Prieske, Olaf and Moran, Jason and Ramirez-Campillo, Rodrigo and Nejmaoui, Ali and Granacher, Urs},
title = {The increased effectiveness of loaded versus unloaded plyometric jump training in improving muscle power, speed, change of direction, and kicking-distance performance in prepubertal male soccer players},
series = {International journal of sports physiology and performance : IJSSP},
volume = {15},
journal = {International journal of sports physiology and performance : IJSSP},
number = {2},
publisher = {Human Kinetics},
address = {Champaign, Ill.},
issn = {1555-0265},
doi = {10.1123/ijspp.2018-0866},
pages = {189 -- 195},
year = {2020},
abstract = {Purpose: To examine the effects of loaded (LPJT) versus unloaded plyometric jump training (UPJT) programs on measures of muscle power, speed, change of direction (CoD), and kicking-distance performance in prepubertal male soccer players. Methods: Participants (N = 29) were randomly assigned to a LPJT group (n = 13; age = 13.0 [0.7] y) using weighted vests or UPJT group (n = 16; age = 13.0 [0.5] y) using body mass only. Before and after the intervention, tests for the assessment of proxies of muscle power (ie, countermovement jump, standing long jump); speed (ie, 5-, 10-, and 20-m sprint); CoD (ie, Illinois CoD test, modified 505 agility test); and kicking-distance were conducted. Data were analyzed using magnitude-based inferences. Results: Within-group analyses for the LPJT group showed large and very large improvements for 10-m sprint time (effect size [ES] = 2.00) and modified 505 CoD (ES = 2.83) tests, respectively. For the same group, moderate improvements were observed for the Illinois CoD test (ES = 0.61), 5- and 20-m sprint time test (ES = 1.00 for both the tests), countermovement jump test (ES = 1.00), and the maximal kicking-distance test (ES = 0.90). Small enhancements in the standing long jump test (ES = 0.50) were apparent. Regarding the UPJT group, small improvements were observed for all tests (ES = 0.33-0.57), except 5- and 10-m sprint time (ES = 1.00 and 0.63, respectively). Between-group analyses favored the LPJT group for the modified 505 CoD (ES = 0.61), standing long jump (ES = 0.50), and maximal kicking-distance tests (ES = 0.57), but not for the 5-m sprint time test (ES = 1.00). Only trivial between-group differences were shown for the remaining tests (ES = 0.00-0.09). Conclusion: Overall, LPJT appears to be more effective than UPJT in improving measures of muscle power, speed, CoD, and kicking-distance performance in prepubertal male soccer players.},
language = {en}
}
@article{MoranPaxtonJonesetal.2020,
author = {Moran, Jason and Paxton, Kevin and Jones, Ben and Granacher, Urs and Sandercock, Gavin Rh and Hope, Edward and Ramirez-Campillo, Rodrigo},
title = {Variable long-term developmental trajectories of short sprint speed and jumping height in English Premier League academy soccer players: an applied case study},
series = {Journal of sports sciences},
volume = {38},
journal = {Journal of sports sciences},
number = {22},
publisher = {Routledge, Taylor \& Francis Group},
address = {London},
issn = {0264-0414},
doi = {10.1080/02640414.2020.1792689},
pages = {2525 -- 2531},
year = {2020},
abstract = {Growth and maturation affect long term physical performance, making the appraisal of athletic ability difficult. We sought to longitudinally track youth soccer players to assess the developmental trajectory of athletic performance over a 6-year period in an English Premier League academy. Age-specific z-scores were calculated for sprint and jump performance from a sample of male youth soccer players (n = 140). A case study approach was used to analyse the longitudinal curves of the six players with the longest tenure. The trajectories of the sprint times of players 1 and 3 were characterised by a marked difference in respective performance levels up until peak height velocity (PHV) when player 1 achieved a substantial increase in sprint speed and player 3 experienced a large decrease. Player 5 was consistently a better performer than player 2 until PHV when the sprint and jump performance of the former markedly decreased and he was overtaken by the latter. Fluctuations in players' physical performance can occur quickly and in drastic fashion. Coaches must be aware that suppressed, or inflated, performance could be temporary and selection and deselection decisions should not be made based on information gathered over a short time period.},
language = {en}
}
@article{ChaabenePrieskeMoranetal.2020,
author = {Chaabene, Helmi and Prieske, Olaf and Moran, Jason and Negra, Yassine and Attia, Ahmed and Granacher, Urs},
title = {Effects of resistance training on Change-of-Direction speed in youth and young physically active and athletic adults: a systematic review with meta-analysis},
series = {Sports medicine : the world's premier sports medicine preview journal},
volume = {50},
journal = {Sports medicine : the world's premier sports medicine preview journal},
number = {8},
publisher = {Springer},
address = {Berlin [u.a.]},
issn = {0112-1642},
doi = {10.1007/s40279-020-01293-w},
pages = {1483 -- 1499},
year = {2020},
abstract = {Background Change-of-direction (CoD) speed is a physical fitness attribute in many field-based team and individual sports. To date, no systematic review with meta-analysis available has examined the effects of resistance training (RT) on CoD speed in youth and adults. Objective To aggregate the effects of RT on CoD speed in youth and young physically active and athletic adults, and to identify the key RT programme variables for training prescription. Data sources A systematic literature search was conducted with PubMed, Web of Science, and Google Scholar, with no date restrictions, up to October 2019, to identify studies related to the effects of RT on CoD speed. Study Eligibility Criteria Only controlled studies with baseline and follow-up measures were included if they examined the effects of RT (i.e., muscle actions against external resistances) on CoD speed in healthy youth (8-18 years) and young physically active/athletic male or female adults (19-28 years). Study Appraisal and Synthesis Methods A random-effects model was used to calculate weighted standardised mean differences (SMD) between intervention and control groups. In addition, an independent single training factor analysis (i.e., RT frequency, intensity, volume) was undertaken. Further, to verify if any RT variable moderated effects on CoD speed, a multivariate random-effects meta-regression was conducted. The methodological quality of the included studies was assessed using the physiotherapy evidence database (PEDro) scale. Results Fifteen studies, comprising 19 experimental groups, were included. The methodological quality of the studies was acceptable with a median PEDro score of 6. There was a significant large effect size of RT on CoD speed across all studies (SMD = - 0.82 [- 1.14 to - 0.49]). Subgroup analyses showed large effect sizes on CoD speed in males (SMD = - 0.95) contrasting with moderate improvements in females (SMD = - 0.60). There were large effect sizes on CoD speed in children (SMD = - 1.28) and adolescents (SMD = - 1.21) contrasting with moderate effects in adults (SMD = - 0.63). There was a moderate effect in elite athletes (SMD = - 0.69) contrasting with a large effect in subelite athletes (SMD = - 0.86). Differences between subgroups were not statistically significant. Similar improvements were observed regarding the effects of independently computed training variables. In terms of RT frequency, our results indicated that two sessions per week induced large effects on CoD speed (SMD = - 1.07) while programmes with three sessions resulted in moderate effects (SMD = - 0.53). For total training intervention duration, we observed large effects for <= 8 weeks (SMD = - 0.81) and > 8 weeks (SMD = - 0.85). For single session duration, we found large effects for <= 30 min and >= 45 min (both SMD = - 1.00). In terms of number of training sessions, we identified large effects for <= 16 sessions (SMD = - 0.83) and > 16 sessions (SMD = - 0.81). For training intensity, we found moderate effects for light-to-moderate (SMD = - 0.76) and vigorous-to-near maximal intensities (SMD = - 0.77). With regards to RT type, we observed large effects for free weights (SMD = - 0.99) and machine-based training (SMD = - 0.80). For combined free weights and machine-based training, moderate effects were identified (SMD = - 0.77). The meta-regression outcomes showed that none of the included training variables significantly predicted the effects of RT on CoD speed (R-2 = 0.00). Conclusions RT seems to be an effective means to improve CoD speed in youth and young physically active and athletic adults. Our findings indicate that the impact of RT on CoD speed may be more prominent in males than in females and in youth than in adults. Additionally, independently computed single factor analyses for different training variables showed that higher compared with lower RT intensities, frequencies, and volumes appear not to have an advantage on the magnitude of CoD speed improvements. In terms of RT type, similar improvements were observed following machine-based and free weights training.},
language = {en}
}
@article{PrieskeBehrensChaabeneetal.2020,
author = {Prieske, Olaf and Behrens, Martin and Chaabene, Helmi and Granacher, Urs and Maffiuletti, Nicola A.},
title = {Time to differentiate postactivation "potentiation" from "performance enhancement" in the strength and conditioning community},
series = {Sports medicine : the world's premier sports medicine preview journal},
volume = {50},
journal = {Sports medicine : the world's premier sports medicine preview journal},
number = {9},
publisher = {Springer},
address = {Berlin [u.a.]},
issn = {0112-1642},
doi = {10.1007/s40279-020-01300-0},
pages = {1559 -- 1565},
year = {2020},
abstract = {Coaches and athletes in elite sports are constantly seeking to use innovative and advanced training strategies to efficiently improve strength/power performance in already highly-trained individuals. In this regard, high-intensity conditioning contractions have become a popular means to induce acute improvements primarily in muscle contractile properties, which are supposed to translate to subsequent power performances. This performance-enhancing physiological mechanism has previously been called postactivation potentiation (PAP). However, in contrast to the traditional mechanistic understanding of PAP that is based on electrically-evoked twitch properties, an increasing number of studies used the term PAP while referring to acute performance enhancements, even if physiological measures of PAP were not directly assessed. In this current opinion article, we compare the two main approaches (i.e., mechanistic vs. performance) used in the literature to describe PAP effects. We additionally discuss potential misconceptions in the general use of the term PAP. Studies showed that mechanistic and performance-related PAP approaches have different characteristics in terms of the applied research field (basic vs. applied), effective conditioning contractions (e.g., stimulated vs. voluntary), verification (lab-based vs. field tests), effects (twitch peak force vs. maximal voluntary strength), occurrence (consistent vs. inconsistent), and time course (largest effect immediately after vs. similar to 7 min after the conditioning contraction). Moreover, cross-sectional studies revealed inconsistent and trivial-to-large-sized associations between selected measures of mechanistic (e.g., twitch peak force) vs. performance-related PAP approaches (e.g., jump height). In an attempt to avoid misconceptions related to the two different PAP approaches, we propose to use two different terms. Postactivation potentiation should only be used to indicate the increase in muscular force/torque production during an electrically-evoked twitch. In contrast, postactivation performance enhancement (PAPE) should be used to refer to the enhancement of measures of maximal strength, power, and speed following conditioning contractions. The implementation of this terminology would help to better differentiate between mechanistic and performance-related PAP approaches. This is important from a physiological point of view, but also when it comes to aggregating findings from PAP studies, e.g., in the form of meta-analyses, and translating these findings to the field of strength and conditioning.},
language = {en}
}
@article{AzadianMajlesiJafarnezhadgeroetal.2020,
author = {Azadian, Elaheh and Majlesi, Mahdi and Jafarnezhadgero, Amir Ali and Granacher, Urs},
title = {The impact of hearing loss on three-dimensional lower limb joint torques during walking in prepubertal boys},
series = {Journal of bodywork and movement therapies},
volume = {24},
journal = {Journal of bodywork and movement therapies},
number = {2},
publisher = {Elsevier},
address = {Amsterdam},
issn = {1360-8592},
doi = {10.1016/j.jbmt.2019.10.013},
pages = {123 -- 129},
year = {2020},
abstract = {Introduction: In children, the impact of hearing loss on biomechanical gait parameters is not well understood. Thus, the objectives of this study were to examine three-dimensional lower limb joint torques in deaf compared to age-matched healthy (hearing) children while walking at preferred gait speed. Methods: Thirty prepubertal boys aged 8-14 were enrolled in this study and divided into a group with hearing loss (deaf group) and an age-matched healthy control. Three-dimensional joint torques were analyzed during barefoot walking at preferred speed using Kistler force plates and a Vicon motion capture system. Results: Findings revealed that boys with hearing loss showed lower joint torques in ankle evertors, knee flexors, abductors and internal rotators as well as in hip internal rotators in both, the dominant and non-dominant lower limbs (all p < 0.05; d = 1.23-7.00; 14-79\%). Further, in the dominant limb, larger peak ankle dorsiflexor (p < 0.001; d = 1.83; 129\%), knee adductor (p < 0.001; d = 3.20; 800\%), and hip adductor torques (p < 0.001; d = 2.62; 350\%) were found in deaf participants compared with controls. Conclusion: The observed altered lower limb torques during walking are indicative of unstable gait in children with hearing loss. More research is needed to elucidate whether physical training (e.g., balance and/or gait training) has the potential to improve walking performance in this patient group. (C) 2019 Elsevier Ltd. All rights reserved.},
language = {en}
}
@article{HortobagyiLesinskiGaebleretal.2015,
author = {Hortob{\´a}gyi, Tibor and Lesinski, Melanie and G{\"a}bler, Martijn and VanSwearingen, Jessie M. and Malatesta, Davide and Granacher, Urs},
title = {Effects of three types of exercise interventions on healthy old adults' gait speed},
series = {Sports medicine},
volume = {45},
journal = {Sports medicine},
publisher = {Springer},
address = {Berlin},
issn = {1179-2035},
doi = {10.1007/s40279-015-0371-2},
pages = {1627 -- 1643},
year = {2015},
abstract = {Background: Habitual walking speed predicts many clinical conditions later in life, but it declines with age. However, which particular exercise intervention can minimize the age-related gait speed loss is unclear. Purpose: Our objective was to determine the effects of strength, power, coordination, and multimodal exercise training on healthy old adults' habitual and fast gait speed. Methods: We performed a computerized systematic literature search in PubMed and Web of Knowledge from January 1984 up to December 2014. Search terms included 'Resistance training', 'power training', 'coordination training', 'multimodal training', and 'gait speed (outcome term). Inclusion criteria were articles available in full text, publication period over past 30 years, human species, journal articles, clinical trials, randomized controlled trials, English as publication language, and subject age C65 years. The methodological quality of all eligible intervention studies was assessed using the Physiotherapy Evidence Database (PEDro) scale. We computed weighted average standardized mean differences of the intervention-induced adaptations in gait speed using a random-effects model and tested for overall and individual intervention effects relative to no-exercise controls. Results: A total of 42 studies (mean PEDro score of 5.0 +/- 1.2) were included in the analyses (2495 healthy old adults; age 74.2 years [64.4-82.7]; body mass 69.9 +/- 4.9 kg, height 1.64 +/- 0.05 m, body mass index 26.4 +/- 1.9 kg/m(2), and gait speed 1.22 +/- 0.18 m/s). The search identified only one power training study, therefore the subsequent analyses focused only on the effects of resistance, coordination, and multimodal training on gait speed. The three types of intervention improved gait speed in the three experimental groups combined (n = 1297) by 0.10 m/s (+/- 0.12) or 8.4 \% (+/- 9.7), with a large effect size (ES) of 0.84. Resistance (24 studies; n = 613; 0.11 m/s; 9.3 \%; ES: 0.84), coordination (eight studies, n = 198; 0.09 m/s; 7.6 \%; ES: 0.76), and multimodal training (19 studies; n = 486; 0.09 m/s; 8.4 \%, ES: 0.86) increased gait speed statistically and similarly. Conclusions: Commonly used exercise interventions can functionally and clinically increase habitual and fast gait speed and help slow the loss of gait speed or delay its onset.},
language = {en}
}
@article{JafarnezhadgeroFatollahiGranacher2022,
author = {Jafarnezhadgero, Amir Ali and Fatollahi, Amir and Granacher, Urs},
title = {Eight weeks of exercising on sand has positive effects on biomechanics of walking and muscle activities in individuals with pronated feet},
series = {Sports : open access journal},
volume = {10},
journal = {Sports : open access journal},
number = {5},
publisher = {MDPI},
address = {Basel},
issn = {2075-4663},
doi = {10.3390/sports10050070},
pages = {16},
year = {2022},
abstract = {This study aimed to investigate the effects of eight weeks of barefoot running exercise on sand versus control on measures of walking kinetics and muscle activities in individuals with diagnosed pronated feet. Sixty physically active male adults with pronated feet were randomly allocated into an intervention or a waiting control group. The intervention group conducted an 8-weeks progressive barefoot running exercise program on sand (e.g., short sprints) with three weekly sessions. Pre and post intervention, participants walked at a constant speed of 1.3 m/s +/- 5\% on a 18 m walkway with a force plate embedded in the middle of the walkway. Results showed significant group-by-time interactions for peak impact vertical and lateral ground reaction forces. Training but not control resulted in significantly lower peak impact vertical and lateral ground reaction forces. Significant group-by-time interactions were observed for vastus lateralis activity during the loading phase. Training-induced increases were found for the vastus lateralis in the intervention but not in the control group. This study revealed that the applied exercise program is a suitable means to absorb ground reaction forces (e.g., lower impact vertical and lateral peaks) and increase activities of selected lower limb muscles (e.g., vastus lateralis) when walking on stable ground.},
language = {en}
}
@article{GebelLehmannGranacher2020,
author = {Gebel, Arnd and Lehmann, Tim and Granacher, Urs},
title = {Balance task difficulty affects postural sway and cortical activity in healthy adolescents},
series = {Experimental brain research},
volume = {238},
journal = {Experimental brain research},
number = {5},
publisher = {Springer},
address = {New York},
issn = {0014-4819},
doi = {10.1007/s00221-020-05810-1},
pages = {1323 -- 1333},
year = {2020},
abstract = {Electroencephalographic (EEG) research indicates changes in adults' low frequency bands of frontoparietal brain areas executing different balance tasks with increasing postural demands. However, this issue is unsolved for adolescents when performing the same balance task with increasing difficulty. Therefore, we examined the effects of a progressively increasing balance task difficulty on balance performance and brain activity in adolescents. Thirteen healthy adolescents aged 16-17 year performed tests in bipedal upright stance on a balance board with six progressively increasing levels of task difficulty. Postural sway and cortical activity were recorded simultaneously using a pressure sensitive measuring system and EEG. The power spectrum was analyzed for theta (4-7 Hz) and alpha-2 (10-12 Hz) frequency bands in pre-defined frontal, central, and parietal clusters of electrocortical sources. Repeated measures analysis of variance (rmANOVA) showed a significant main effect of task difficulty for postural sway (p < 0.001; d = 6.36). Concomitantly, the power spectrum changed in frontal, bilateral central, and bilateral parietal clusters. RmANOVAs revealed significant main effects of task difficulty for theta band power in the frontal (p < 0.001, d = 1.80) and both central clusters (left: p < 0.001, d = 1.49; right: p < 0.001, d = 1.42) as well as for alpha-2 band power in both parietal clusters (left: p < 0.001, d = 1.39; right: p < 0.001, d = 1.05) and in the central right cluster (p = 0.005, d = 0.92). Increases in theta band power (frontal, central) and decreases in alpha-2 power (central, parietal) with increasing balance task difficulty may reflect increased attentional processes and/or error monitoring as well as increased sensory information processing due to increasing postural demands. In general, our findings are mostly in agreement with studies conducted in adults. Similar to adult studies, our data with adolescents indicated the involvement of frontoparietal brain areas in the regulation of postural control. In addition, we detected that activity of selected brain areas (e.g., bilateral central) changed with increasing postural demands.},
language = {en}
}
@article{SandauGranacher2020,
author = {Sandau, Ingo and Granacher, Urs},
title = {Effects of the barbell load on the acceleration phase during the snatch in elite Olympic weightlifting},
series = {Sports},
volume = {8},
journal = {Sports},
number = {5},
publisher = {MDPI},
address = {Basel},
issn = {2075-4663},
doi = {10.3390/sports8050059},
pages = {10},
year = {2020},
abstract = {The load-depended loss of vertical barbell velocity at the end of the acceleration phase limits the maximum weight that can be lifted. Thus, the purpose of this study was to analyze how increased barbell loads affect the vertical barbell velocity in the sub-phases of the acceleration phase during the snatch. It was hypothesized that the load-dependent velocity loss at the end of the acceleration phase is primarily associated with a velocity loss during the 1st pull. For this purpose, 14 male elite weightlifters lifted seven load-stages from 70-100\% of their personal best in the snatch. The load-velocity relationship was calculated using linear regression analysis to determine the velocity loss at 1st pull, transition, and 2nd pull. A group mean data contrast analysis revealed the highest load-dependent velocity loss for the 1st pull (t = 1.85, p = 0.044, g = 0.49 [-0.05, 1.04]) which confirmed our study hypothesis. In contrast to the group mean data, the individual athlete showed a unique response to increased loads during the acceleration sub-phases of the snatch. With the proposed method, individualized training recommendations on exercise selection and loading schemes can be derived to specifically improve the sub-phases of the snatch acceleration phase. Furthermore, the results highlight the importance of single-subject assessment when working with elite athletes in Olympic weightlifting.},
language = {en}
}
@article{JafarnezhadgeroAnvariGranacher2020,
author = {Jafarnezhadgero, Amir Ali and Anvari, Maryam and Granacher, Urs},
title = {Long-term effects of shoe mileage on ground reaction forces and lower limb muscle activities during walking in individuals with genu varus},
series = {Clinical biomechanics},
volume = {73},
journal = {Clinical biomechanics},
publisher = {Elsevier},
address = {Oxford},
issn = {0268-0033},
doi = {10.1016/j.clinbiomech.2020.01.006},
pages = {55 -- 62},
year = {2020},
abstract = {Background: Shoe mileage is an important factor that may influence the risk of sustaining injuries during walking. The aims of this study were to examine the effects of shoe mileage on ground reaction forces and activity of lower limb muscles during walking in genu varus individuals compared with controls. Methods: Fifteen healthy and 15 genu varus females received a new pair of running shoes. They were asked to wear these shoes over 6 months. Pre and post intervention, mechanical shoe testing was conducted and ground reaction forces and muscle activities of the right leg were recorded during walking at preferred gait speed. Findings: Significant group-by-time interactions were found for shoe stiffness, antero-posterior and vertical impact peak. We observed higher shoe stiffness and lower impact peaks after intervention in both groups with larger effect sizes in genu varus. Significant group-by-time interactions were identified for vastus medialis (loading phase) and rectus femoris (loading and push-off). For vastus medialis, significant decreases were found from pre-to-post during the loading phase in the control group. Rectus femoris activity was higher post intervention during the loading and push-off phases in both groups with larger effect sizes in genu varus. Interpretation: Our findings indicate that the observed changes in ground reaction forces are more prominent in genu varus individuals. Together with our findings on shoe stiffness, it seems appropriate to change running shoes after an intense wearing time of 6 months, particularly in genu varus individuals.},
language = {en}
}
@article{HortobagyiGranacherFernandezdelOlmoetal.2020,
author = {Hortobagyi, Tibor and Granacher, Urs and Fernandez-del-Olmo, Miguel and Howatson, Glyn and Manca, Andrea and Deriu, Franca and Taube, Wolfgang and Gruber, Markus and Marquez, Gonzalo and Lundbye-Jensen, Jesper and Colomer-Poveda, David},
title = {Functional relevance of resistance training-induced neuroplasticity in health and disease},
series = {Neuroscience \& biobehavioral reviews : official journal of the International Behavioral Neuroscience Society},
volume = {122},
journal = {Neuroscience \& biobehavioral reviews : official journal of the International Behavioral Neuroscience Society},
publisher = {Elsevier},
address = {Oxford},
issn = {0149-7634},
doi = {10.1016/j.neubiorev.2020.12.019},
pages = {79 -- 91},
year = {2020},
abstract = {Repetitive, monotonic, and effortful voluntary muscle contractions performed for just a few weeks, i.e., resistance training, can substantially increase maximal voluntary force in the practiced task and can also increase gross motor performance. The increase in motor performance is often accompanied by neuroplastic adaptations in the central nervous system. While historical data assigned functional relevance to such adaptations induced by resistance training, this claim has not yet been systematically and critically examined in the context of motor performance across the lifespan in health and disease. A review of muscle activation, brain and peripheral nerve stimulation, and imaging data revealed that increases in motor performance and neuroplasticity tend to be uncoupled, making a mechanistic link between neuroplasticity and motor performance inconclusive. We recommend new approaches, including causal mediation analytical and hypothesis-driven models to substantiate the functional relevance of resistance training-induced neuroplasticity in the improvements of gross motor function across the lifespan in health and disease.},
language = {en}
}
@article{RamirezCampilloMoranOliveretal.2022,
author = {Ramirez-Campillo, Rodrigo and Moran, Jason and Oliver, Jonathan L. and Pedley, Jason S. and Lloyd, Rhodri S. and Granacher, Urs},
title = {Programming Plyometric-Jump Training in Soccer: A Review},
series = {Sports},
volume = {10},
journal = {Sports},
edition = {6},
publisher = {MDPI},
address = {Basel, Schweiz},
issn = {2075-4663},
doi = {10.3390/sports10060094},
pages = {1 -- 20},
year = {2022},
abstract = {The aim of this review was to describe and summarize the scientific literature on programming parameters related to jump or plyometric training in male and female soccer players of different ages and fitness levels. A literature search was conducted in the electronic databases PubMed, Web of Science and Scopus using keywords related to the main topic of this study (e.g., "ballistic" and "plyometric"). According to the PICOS framework, the population for the review was restricted to soccer players, involved in jump or plyometric training. Among 7556 identified studies, 90 were eligible for inclusion. Only 12 studies were found for females. Most studies (n = 52) were conducted with youth male players. Moreover, only 35 studies determined the effectiveness of a given jump training programming factor. Based on the limited available research, it seems that a dose of 7 weeks (1-2 sessions per week), with ~80 jumps (specific of combined types) per session, using near-maximal or maximal intensity, with adequate recovery between repetitions (<15 s), sets (≥30 s) and sessions (≥24-48 h), using progressive overload and taper strategies, using appropriate surfaces (e.g., grass), and applied in a well-rested state, when combined with other training methods, would increase the outcome of effective and safe plyometric-jump training interventions aimed at improving soccer players physical fitness. In conclusion, jump training is an effective and easy-to-administer training approach for youth, adult, male and female soccer players. However, optimal programming for plyometric-jump training in soccer is yet to be determined in future research.},
language = {en}
}
@article{ThielePrieskeChaabeneetal.2020,
author = {Thiele, Dirk and Prieske, Olaf and Chaabene, Helmi and Granacher, Urs},
title = {Effects of strength training on physical fitness and sport-specific performance in recreational, sub-elite, and elite rowers},
series = {Journal of sports sciences},
volume = {38},
journal = {Journal of sports sciences},
number = {10},
publisher = {Routledge, Taylor \& Francis Group},
address = {Abingdon},
issn = {0264-0414},
doi = {10.1080/02640414.2020.1745502},
pages = {1186 -- 1195},
year = {2020},
abstract = {The purpose of this systematic review with meta-analysis was to examine the effects of strength training (ST) on selected components of physical fitness (e.g., lower/upper limb maximal strength, muscular endurance, jump performance, cardiorespiratory endurance) and sport-specific performance in rowers. Only studies with an active control group were included if they examined the effects of ST on at least one proxy of physical fitness and/or sport-specific performance in rowers. Weighted and averaged standardized mean differences (SMD) were calculated using random-effects models. Subgroup analyses were computed to identify effects of ST type or expertise level on sport-specific performance. Our analyses revealed significant small effects of ST on lower limb maximal strength (SMD = 0.42, p = 0.05) and on sport-specific performance (SMD = 0.32, p = 0.05). Non-significant effects were found for upper limb maximal strength, upper/lower limb muscular endurance, jump performance, and cardiorespiratory endurance. Subgroup analyses for ST type and expertise level showed non-significant differences between the respective subgroups of rowers (p >= 0.32). Our systematic review with meta-analysis indicated that ST is an effective means for improving lower limb maximal strength and sport-specific performance in rowers. However, ST-induced effects are neither modulated by ST type nor rowers' expertise level.},
language = {en}
}
@article{LesinskiHerzSchmelcheretal.2020,
author = {Lesinski, Melanie and Herz, Michael and Schmelcher, Alina and Granacher, Urs},
title = {Effects of resistance training on physical fitness in healthy children and adolescents},
series = {Sports medicine},
volume = {50},
journal = {Sports medicine},
number = {11},
publisher = {Springer},
address = {Northcote},
issn = {0112-1642},
doi = {10.1007/s40279-020-01327-3},
pages = {1901 -- 1928},
year = {2020},
abstract = {Background Over the past decades, an exponential growth has occurred with regards to the number of scientific publications including meta-analyses on youth resistance training (RT). Accordingly, it is timely to summarize findings from meta-analyses in the form of an umbrella review. Objectives To systematically review and summarise the findings of published meta-analyses that investigated the effects of RT on physical fitness in children and adolescents. Design Systematic umbrella review of meta-analyses. Data Sources Meta-analyses were identified using systematic literature searches in the databases PubMed, Web of Science, and Cochrane Library. Eligibility Criteria for Selecting Meta-analyses Meta-analyses that examined the effects of RT on physical fitness (e.g., muscle strength, muscle power) in healthy youth (<= 18 years). Results Fourteen meta-analyses were included in this umbrella review. Eleven of these meta-analyses reported between-subject effect sizes which are important to eliminate bias due to growth and maturation. RT produced medium-to-large effects on muscle strength, small-to-large effects on muscle power, small-to-medium effects on linear sprint, a medium effect on agility/change-of-direction speed, small-to-large effects on throwing performance, and a medium effect on sport-specific enhancement. There were few consistent moderating effects of maturation, age, sex, expertise level, or RT type on muscle strength and muscle power across the included meta-analyses. The analysed meta-analyses showed low-to-moderate methodological quality (AMSTAR2) as well as presented evidence of low-to-very low quality (GRADE). Conclusion This umbrella review proved the effectiveness of RT in youth on a high evidence level. The magnitude of effects varies according to the respective outcome measure and it appears to follow the principle of training specificity. Larger effect sizes were found for strength-related outcome measures. Future studies should consistently report data on participants' maturational status. More research is needed with prepubertal children and girls, irrespective of their maturational status.},
language = {en}
}
@article{FuehnerKlieglArntzetal.2020,
author = {F{\"u}hner, Thea Heidi and Kliegl, Reinhold and Arntz, Fabian and Kriemler, Susi and Granacher, Urs},
title = {An update on secular trends in physical fitness of children and adolescents from 1972 to 2015},
series = {Sports medicine},
volume = {51},
journal = {Sports medicine},
number = {2},
publisher = {Springer},
address = {Northcote},
issn = {0112-1642},
doi = {10.1007/s40279-020-01373-x},
pages = {303 -- 320},
year = {2020},
abstract = {Background There is evidence that physical fitness of children and adolescents (particularly cardiorespiratory endurance) has declined globally over the past decades. Ever since the first reports on negative trends in physical fitness, efforts have been undertaken by for instance the World Health Organization (WHO) to promote physical activity and fitness in children and adolescents. Therefore, it is timely to re-analyze the literature to examine whether previous reports on secular declines in physical fitness are still detectable or whether they need to be updated. Objectives The objective of this systematic review is to provide an 'update' on secular trends in selected components of physical fitness (i.e., cardiorespiratory endurance, relative muscle strength, proxies of muscle power, speed) in children and adolescents aged 6-18 years. Data Sources A systematic computerized literature search was conducted in the electronic databases PubMed and Web of Science to locate studies that explicitly reported secular trends in physical fitness of children and adolescents. Study Eligibility Criteria Studies were included in this systematic review if they examined secular trends between at least two time points across a minimum of 5 years. In addition, they had to document secular trends in any measure of cardiorespiratory endurance, relative muscle strength, proxies of muscle power or speed in apparently healthy children and adolescents aged 6-18 years. Study Appraisal and Synthesis Methods The included studies were coded for the following criteria: nation, physical fitness component (cardiorespiratory endurance, relative muscle strength, proxies of muscle power, speed), chronological age, sex (boys vs. girls), and year of assessment. Scores were standardized (i.e., converted to z scores) with sample-weighted means and standard deviations, pooled across sex and year of assessment within cells defined by study, test, and children's age. Results The original search identified 524 hits. In the end, 22 studies met the inclusion criteria for review. The observation period was between 1972 and 2015. Fifteen of the 22 studies used tests for cardiorespiratory endurance, eight for relative muscle strength, eleven for proxies of muscle power, and eight for speed. Measures of cardiorespiratory endurance exhibited a large initial increase and an equally large subsequent decrease, but the decrease appears to have reached a floor for all children between 2010 and 2015. Measures of relative muscle strength showed a general trend towards a small increase. Measures of proxies of muscle power indicated an overall small negative quadratic trend. For measures of speed, a small-to-medium increase was observed in recent years. Limitations Biological maturity was not considered in the analysis because biological maturity was not reported in most included studies. Conclusions Negative secular trends were particularly found for cardiorespiratory endurance between 1986 and 2010-12, irrespective of sex. Relative muscle strength and speed showed small increases while proxies of muscle power declined. Although the negative trend in cardiorespiratory endurance appears to have reached a floor in recent years, because of its association with markers of health, we recommend further initiatives in PA and fitness promotion for children and adolescents. More specifically, public health efforts should focus on exercise that increases cardiorespiratory endurance to prevent adverse health effects (i.e.
, overweight and obesity) and muscle strength to lay a foundation for motor skill learning.},
language = {en}
}
@article{LesinskiPrieskeChaabeneetal.2021,
author = {Lesinski, Melanie and Prieske, Olaf and Chaabene, Helmi and Granacher, Urs},
title = {Seasonal effects of strength endurance vs. power training in young female soccer athletes},
series = {Journal of strength and conditioning research : the research journal of the NSCA},
volume = {35},
journal = {Journal of strength and conditioning research : the research journal of the NSCA},
number = {Supplement 12},
publisher = {Lippincott Williams \& Wilkins},
address = {Philadelphia},
issn = {1064-8011},
doi = {10.1519/JSC.0000000000003564},
pages = {S90 -- S96},
year = {2021},
abstract = {Lesinski, M, Prieske, O, Chaabene, H, and Granacher, U. Seasonal effects of strength endurance vs. power training in young female soccer athletes. J Strength Cond Res 35(12S): S90-S96, 2021-This study examined the seasonal effects of strength endurance training (SET) vs. power training (PT) on physical fitness and body composition in young female soccer players. Thirty-six young female elite soccer players (15 +/- 1 years; maturity offset +3 +/- 1 years) were allocated to progressive SET (n = 19) or PT (n = 17). Over the course of one soccer season, SET performed slow movement velocity, moderate intensity (50-60\% of the 1 repetition maximum [1RM]; 20-40 repetitions) strength exercises while PT performed moderate-to-high intensity (50-95\% of the 1RM; 3-8 repetitions), high movement velocity strength exercises (2 sessions center dot wk(-1)). Before and after training, tests were performed for the assessment of muscle strength (1RM leg press), jump performance (countermovement jump [CMJ], drop jump [DJ]), muscular endurance (ventral Bourban test), linear speed (10 m, 20 m), change-of-direction (CoD) speed (T-test), dynamic balance (Y-balance test), sport-specific performance (kicking velocity), and body composition (lean body mass and fat mass). An analysis of covariance was used to test for between-group differences at post-test with baseline values as covariate. No significant between-group differences were observed in terms of total training volume over the respective soccer seasons (p = 0.069; d = 0.68). At post-test, SET showed significantly better ventral Bourban and T-test performances (d = 1.28-2.28; p = 0.000-0.001) compared with PT. However, PT resulted in significantly better 1RM leg press, DJ, 10-m, and 20-m sprint performances (d = 0.85-1.44; p = 0.000-0.026). No significant between-group differences were observed at post-test for CMJ, Y-balance test, kicking performance, and body composition (d = 0.20-0.74, p = 0.051-0.594). Our findings are mainly in accordance with the principle of training specificity. Both SET and PT are recommended to be implemented in young female elite soccer players according to the respective training period.},
language = {en}
}
@article{JafarnezhadgeroNorooziFakhriMirzanagetal.2022,
author = {Jafarnezhadgero, Amir Ali and Noroozi, Raha and Fakhri Mirzanag, Ehsan and Granacher, Urs and de Souza Castelo Oliveira, Anderson},
title = {The Impact of COVID-19 and Muscle Fatigue on Cardiorespiratory Fitness and Running Kinetics in Female Recreational Runners},
series = {Frontiers in Physiology},
volume = {13},
journal = {Frontiers in Physiology},
publisher = {Frontiers},
address = {Lausanne, Schweiz},
issn = {1664-042X},
doi = {10.3389/fphys.2022.942589},
pages = {1 -- 10},
year = {2022},
abstract = {Background: There is evidence that fully recovered COVID-19 patients usually resume physical exercise, but do not perform at the same intensity level performed prior to infection. The aim of this study was to evaluate the impact of COVID-19 infection and recovery as well as muscle fatigue on cardiorespiratory fitness and running biomechanics in female recreational runners. Methods: Twenty-eight females were divided into a group of hospitalized and recovered COVID-19 patients (COV, n = 14, at least 14 days following recovery) and a group of healthy age-matched controls (CTR, n = 14). Ground reaction forces from stepping on a force plate while barefoot overground running at 3.3 m/s was measured before and after a fatiguing protocol. The fatigue protocol consisted of incrementally increasing running speed until reaching a score of 13 on the 6-20 Borg scale, followed by steady-state running until exhaustion. The effects of group and fatigue were assessed for steady-state running duration, steady-state running speed, ground contact time, vertical instantaneous loading rate and peak propulsion force. Results: COV runners completed only 56\% of the running time achieved by the CTR (p < 0.0001), and at a 26\% slower steady-state running speed (p < 0.0001). There were fatigue-related reductions in loading rate (p = 0.004) without group differences. Increased ground contact time (p = 0.002) and reduced peak propulsion force (p = 0.005) were found for COV when compared to CTR. Conclusion: Our results suggest that female runners who recovered from COVID-19 showed compromised running endurance and altered running kinetics in the form of longer stance periods and weaker propulsion forces. More research is needed in this area using larger sample sizes to confirm our study findings.},
language = {en}
}
@article{FernandezFernandezGranacherMartinezMartinetal.2022,
author = {Fernandez-Fernandez, Jaime and Granacher, Urs and Martinez-Martin, Isidoro and Garcia-Tormo, Jos{\´e} Vicente and Herrero-Molleda, Alba and Barbado, David and Garc{\´i}a L{\´o}pez, Juan},
title = {Physical fitness and throwing speed in U13 versus U15 male handball players},
series = {BMC Sports Science, Medicine and Rehabilitation},
volume = {14},
journal = {BMC Sports Science, Medicine and Rehabilitation},
publisher = {Springer},
address = {London},
issn = {1758-2555},
doi = {10.1186/s13102-022-00507-0},
pages = {13},
year = {2022},
abstract = {Background The aim of this study was to analyze the shoulder functional profile (rotation range of motion [ROM] and strength), upper and lower body performance, and throwing speed of U13 versus U15 male handball players, and to establish the relationship between these measures of physical fitness and throwing speed. Methods One-hundred and nineteen young male handball players (under (U)-13 (U13) [n = 85]) and U15 [n = 34]) volunteered to participate in this study. The participating athletes had a mean background of sytematic handball training of 5.5 ± 2.8 years and they exercised on average 540 ± 10.1 min per week including sport-specific team handball training and strength and conditioning programs. Players were tested for passive shoulder range-of-motion (ROM) for both internal (IR) and external rotation (ER) and isometric strength (i.e., IR and ER) of the dominant/non-dominant shoulders, overhead medicine ball throw (OMB), hip isometric abductor (ABD) and adductor (ADD) strength, hip ROM, jumps (countermovement jump [CMJ] and triple leg-hop [3H] for distance), linear sprint test, modified 505 change-of-direction (COD) test and handball throwing speed (7 m [HT7] and 9 m [HT9]). Results U15 players outperformed U13 in upper (i.e., HT7 and HT9 speed, OMB, absolute IR and ER strength of the dominant and non-dominant sides; Cohen's d: 0.76-2.13) and lower body (i.e., CMJ, 3H, 20-m sprint and COD, hip ABD and ADD; d: 0.70-2.33) performance measures. Regarding shoulder ROM outcomes, a lower IR ROM was found of the dominant side in the U15 group compared to the U13 and a higher ER ROM on both sides in U15 (d: 0.76-1.04). It seems that primarily anthropometric characteristics (i.e., body height, body mass) and upper body strength/power (OMB distance) are the most important factors that explain the throw speed variance in male handball players, particularly in U13. Conclusions Findings from this study imply that regular performance monitoring is important for performance development and for minimizing injury risk of the shoulder in both age categories of young male handball players. Besides measures of physical fitness, anthropometric data should be recorded because handball throwing performance is related to these measures.},
language = {en}
}
@article{DelfanJuybariGorganiFiruzjaeeetal.2022,
author = {Delfan, Maryam and Juybari, Raheleh Amadeh and Gorgani-Firuzjaee, Sattar and Nielsen, Jens H{\o}iriis and Delfan, Neda and Laher, Ismail and Saeidi, Ayoub and Granacher, Urs and Zouhal, Hassane},
title = {High-Intensity Interval Training Improves Cardiac Function by miR-206 Dependent HSP60 Induction in Diabetic Rats},
series = {Frontiers in Cardiovascular Medicine},
volume = {9},
journal = {Frontiers in Cardiovascular Medicine},
publisher = {Frontiers},
address = {Lausanne, Schweiz},
issn = {2297-055X},
doi = {10.3389/fcvm.2022.927956},
pages = {1 -- 11},
year = {2022},
abstract = {Objective: A role for microRNAs is implicated in several biological and pathological processes. We investigated the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on molecular markers of diabetic cardiomyopathy in rats. Methods: Eighteen male Wistar rats (260 ± 10 g; aged 8 weeks) with streptozotocin (STZ)-induced type 1 diabetes mellitus (55 mg/kg, IP) were randomly allocated to three groups: control, MICT, and HIIT. The two different training protocols were performed 5 days each week for 5 weeks. Cardiac performance (end-systolic and end-diastolic dimensions, ejection fraction), the expression of miR-206, HSP60, and markers of apoptosis (cleaved PARP and cytochrome C) were determined at the end of the exercise interventions. Results: Both exercise interventions (HIIT and MICT) decreased blood glucose levels and improved cardiac performance, with greater changes in the HIIT group (p < 0.001, η2: 0.909). While the expressions of miR-206 and apoptotic markers decreased in both training protocols (p < 0.001, η2: 0.967), HIIT caused greater reductions in apoptotic markers and produced a 20\% greater reduction in miR-206 compared with the MICT protocol (p < 0.001). Furthermore, both training protocols enhanced the expression of HSP60 (p < 0.001, η2: 0.976), with a nearly 50\% greater increase in the HIIT group compared with MICT. Conclusions: Our results indicate that both exercise protocols, HIIT and MICT, have the potential to reduce diabetic cardiomyopathy by modifying the expression of miR-206 and its downstream targets of apoptosis. It seems however that HIIT is even more effective than MICT to modulate these molecular markers.},
language = {en}
}
@article{FuehnerGranacherGolleetal.2022,
author = {F{\"u}hner, Thea Heidi and Granacher, Urs and Golle, Kathleen and Kliegl, Reinhold},
title = {Effect of timing of school enrollment on physical fitness in third graders},
series = {Scientific Reports},
volume = {12},
journal = {Scientific Reports},
publisher = {Springer Nature},
address = {London},
issn = {2045-2322},
doi = {10.1038/s41598-022-11710-x},
pages = {1 -- 11},
year = {2022},
abstract = {Timing of initial school enrollment may vary considerably for various reasons such as early or delayed enrollment, skipped or repeated school classes. Accordingly, the age range within school grades includes older-(OTK) and younger-than-keyage (YTK) children. Hardly any information is available on the impact of timing of school enrollment on physical fitness. There is evidence from a related research topic showing large differences in academic performance between OTK and YTK children versus keyage children. Thus, the aim of this study was to compare physical fitness of OTK (N = 26,540) and YTK (N = 2586) children versus keyage children (N = 108,295) in a representative sample of German third graders. Physical fitness tests comprised cardiorespiratory endurance, coordination, speed, lower, and upper limbs muscle power. Predictions of physical fitness performance for YTK and OTK children were estimated using data from keyage children by taking age, sex, school, and assessment year into account. Data were annually recorded between 2011 and 2019. The difference between observed and predicted z-scores yielded a delta z-score that was used as a dependent variable in the linear mixed models. Findings indicate that OTK children showed poorer performance compared to keyage children, especially in coordination, and that YTK children outperformed keyage children, especially in coordination. Teachers should be aware that OTK children show poorer physical fitness performance compared to keyage children.},
language = {en}
}
@article{FernandezFernandezMoyaRamonSantosRosaetal.2021,
author = {Fernandez-Fernandez, Jaime and Moya-Ramon, Manuel and Santos-Rosa, Francisco Javier and Gantois, Petrus and Nakamura, Fabio Yuzo and Sanz-Rivas, David and Granacher, Urs},
title = {Within-session sequence of the tennis serve training in youth elite players},
series = {International journal of environmental research and public health},
volume = {18},
journal = {International journal of environmental research and public health},
number = {1},
publisher = {MDPI},
address = {Basel},
issn = {1660-4601},
doi = {10.3390/ijerph18010244},
pages = {15},
year = {2021},
abstract = {The influence of muscular fatigue on tennis serve performance within regular training sessions is unclear. Therefore, the aim of the present study was to examine the within-session sequence of the tennis serve in youth tennis. Twenty-five young male (14.9 +/- 0.9 years) and female (14.5 +/- 0.9 years) players participated in this within-subject crossover study, and they were randomly but sex-matched assigned to different training sequences (serve exercise before tennis training (BTS) or after tennis training (ATS)). Pre- and post-tests included serve velocity performance and accuracy, shoulder strength, and range-of-motion (ROM) performance (internal/external rotation). Results showed that after one week of serve training conducted following the ATS sequence, significant decreases were found in serve performance (e.g., speed and accuracy), with standardized differences ranging from d = 0.29 to 1.13, as well as the shoulder function (strength [d = 0.20 to 1.0] and ROM [d = 0.17 to 0.31]) in both female and male players, compared to the BTS sequence. Based on the present findings, it appears more effective to implement serve training before the regular tennis training in youth players. If applied after training, excessive levels of fatigue may cause shoulder imbalances that could be related to an increased injury risk.},
language = {en}
}
@article{DelfanVahedBishopetal.2022,
author = {Delfan, Maryam and Vahed, Alieh and Bishop, David and Juybari, Raheleh Amadeh and Laher, Ismail and Saeidi, Ayoub and Granacher, Urs and Zouhal, Hassane},
title = {Effects of two workload-matched high-intensity interval training protocols on regulatory factors associated with mitochondrial biogenesis in the soleus muscle of diabetic rats},
series = {Frontiers in Physiology},
journal = {Frontiers in Physiology},
publisher = {Frontiers},
address = {Lausanne, Schweiz},
issn = {1664-042X},
doi = {10.3389/fphys.2022.927969},
pages = {1 -- 12},
year = {2022},
abstract = {Aims: High intensity interval training (HIIT) improves mitochondrial characteristics. This study compared the impact of two workload-matched high intensity interval training (HIIT) protocols with different work:recovery ratios on regulatory factors related to mitochondrial biogenesis in the soleus muscle of diabetic rats. Materials and methods: Twenty-four Wistar rats were randomly divided into four equal-sized groups: non-diabetic control, diabetic control (DC), diabetic with long recovery exercise [4-5 × 2-min running at 80\%-90\% of the maximum speed reached with 2-min of recovery at 40\% of the maximum speed reached (DHIIT1:1)], and diabetic with short recovery exercise (5-6 × 2-min running at 80\%-90\% of the maximum speed reached with 1-min of recovery at 30\% of the maximum speed reached [DHIIT2:1]). Both HIIT protocols were completed five times/week for 4 weeks while maintaining equal running distances in each session. Results: Gene and protein expressions of PGC-1α, p53, and citrate synthase of the muscles increased significantly following DHIIT1:1 and DHIIT2:1 compared to DC (p ˂ 0.05). Most parameters, except for PGC-1α protein (p = 0.597), were significantly higher in DHIIT2:1 than in DHIIT1:1 (p ˂ 0.05). Both DHIIT groups showed significant increases in maximum speed with larger increases in DHIIT2:1 compared with DHIIT1:1. Conclusion: Our findings indicate that both HIIT protocols can potently up-regulate gene and protein expression of PGC-1α, p53, and CS. However, DHIIT2:1 has superior effects compared with DHIIT1:1 in improving mitochondrial adaptive responses in diabetic rats.},
language = {en}
}
@article{GebelBuschStelzeletal.2022,
author = {Gebel, Arnd and Busch, Aglaja and Stelzel, Christine and Hortob{\´a}gyi, Tibor and Granacher, Urs},
title = {Effects of Physical and Mental Fatigue on Postural Sway and Cortical Activity in Healthy Young Adults},
series = {Frontiers in Human Neuroscience},
volume = {16},
journal = {Frontiers in Human Neuroscience},
publisher = {Frontiers Media S.A.},
address = {Lausanne, Schweiz},
issn = {1662-5161},
doi = {10.3389/fnhum.2022.871930},
pages = {1 -- 14},
year = {2022},
abstract = {Physical fatigue (PF) negatively affects postural control, resulting in impaired balance performance in young and older adults. Similar effects on postural control can be observed for mental fatigue (MF) mainly in older adults. Controversial results exist for young adults. There is a void in the literature on the effects of fatigue on balance and cortical activity. Therefore, this study aimed to examine the acute effects of PF and MF on postural sway and cortical activity. Fifteen healthy young adults aged 28 ± 3 years participated in this study. MF and PF protocols comprising of an all-out repeated sit-to-stand task and a computer-based attention network test, respectively, were applied in random order. Pre and post fatigue, cortical activity and postural sway (i.e., center of pressure displacements [CoPd], velocity [CoPv], and CoP variability [CV CoPd, CV CoPv]) were tested during a challenging bipedal balance board task. Absolute spectral power was calculated for theta (4-7.5 Hz), alpha-2 (10.5-12.5 Hz), beta-1 (13-18 Hz), and beta-2 (18.5-25 Hz) in frontal, central, and parietal regions of interest (ROI) and baseline-normalized. Inference statistics revealed a significant time-by-fatigue interaction for CoPd (p = 0.009, d = 0.39, Δ 9.2\%) and CoPv (p = 0.009, d = 0.36, Δ 9.2\%), and a significant main effect of time for CoP variability (CV CoPd: p = 0.001, d = 0.84; CV CoPv: p = 0.05, d = 0.62). Post hoc analyses showed a significant increase in CoPd (p = 0.002, d = 1.03) and CoPv (p = 0.003, d = 1.03) following PF but not MF. For cortical activity, a significant time-by-fatigue interaction was found for relative alpha-2 power in parietal (p < 0.001, d = 0.06) areas. Post hoc tests indicated larger alpha-2 power increases after PF (p < 0.001, d = 1.69, Δ 3.9\%) compared to MF (p = 0.001, d = 1.03, Δ 2.5\%). In addition, changes in parietal alpha-2 power and measures of postural sway did not correlate significantly, irrespective of the applied fatigue protocol. No significant changes were found for the other frequency bands, irrespective of the fatigue protocol and ROI under investigation. Thus, the applied PF protocol resulted in increased postural sway (CoPd and CoPv) and CoP variability accompanied by enhanced alpha-2 power in the parietal ROI while MF led to increased CoP variability and alpha-2 power in our sample of young adults. Potential underlying cortical mechanisms responsible for the greater increase in parietal alpha-2 power after PF were discussed but could not be clearly identified as cause. Therefore, further future research is needed to decipher alternative interpretations.},
language = {en}
}
@article{BouamraZouhalRateletal.2022,
author = {Bouamra, Marwa and Zouhal, Hassane and Ratel, S{\´e}bastien and Makhlouf, Issam and Bezrati, Ikram and Chtara, Moktar and Behm, David George and Granacher, Urs and Chaouachi, Anis},
title = {Concurrent Training Promotes Greater Gains on Body Composition and Components of Physical Fitness Than Single-Mode Training (Endurance or Resistance) in Youth With Obesity},
series = {Frontiers in Physiology},
volume = {13},
journal = {Frontiers in Physiology},
publisher = {Frontiers},
address = {Lausanne, Schweiz},
issn = {1664-042X},
doi = {10.3389/fphys.2022.869063},
pages = {1 -- 16},
year = {2022},
abstract = {The prevalence of obesity in the pediatric population has become a major public health issue. Indeed, the dramatic increase of this epidemic causes multiple and harmful consequences, Physical activity, particularly physical exercise, remains to be the cornerstone of interventions against childhood obesity. Given the conflicting findings with reference to the relevant literature addressing the effects of exercise on adiposity and physical fitness outcomes in obese children and adolescents, the effect of duration-matched concurrent training (CT) [50\% resistance (RT) and 50\% high-intensity-interval-training (HIIT)] on body composition and physical fitness in obese youth remains to be elucidated. Thus, the purpose of this study was to examine the effects of 9-weeks of CT compared to RT or HIIT alone, on body composition and selected physical fitness components in healthy sedentary obese youth. Out of 73 participants, only 37; [14 males and 23 females; age 13.4 ± 0.9 years; body-mass-index (BMI): 31.2 ± 4.8 kg·m-2] were eligible and randomized into three groups: HIIT (n = 12): 3-4 sets×12 runs at 80-110\% peak velocity, with 10-s passive recovery between bouts; RT (n = 12): 6 exercises; 3-4 sets × 10 repetition maximum (RM) and CT (n = 13): 50\% serial completion of RT and HIIT. CT promoted significant greater gains compared to HIIT and RT on body composition (p < 0.01, d = large), 6-min-walking test distance (6 MWT-distance) and on 6 MWT-VO2max (p < 0.03, d = large). In addition, CT showed substantially greater improvements than HIIT in the medicine ball throw test (20.2 vs. 13.6\%, p < 0.04, d = large). On the other hand, RT exhibited significantly greater gains in relative hand grip strength (p < 0.03, d = large) and CMJ (p < 0.01, d = large) than HIIT and CT. CT promoted greater benefits for fat, body mass loss and cardiorespiratory fitness than HIIT or RT modalities. This study provides important information for practitioners and therapists on the application of effective exercise regimes with obese youth to induce significant and beneficial body composition changes. The applied CT program and the respective programming parameters in terms of exercise intensity and volume can be used by practitioners as an effective exercise treatment to fight the pandemic overweight and obesity in youth.},
language = {en}
}
@article{AlouiTayechArbiMejrietal.2022,
author = {Aloui, Ali and Tayech, Amel and Arbi Mejri, Mohamed and Makhlouf, Issam and Clark, Cain C. T. and Granacher, Urs and Zouhal, Hassane and Ben Abderrahman, Abderraouf},
title = {Reliability and Validity of a New Taekwondo-Specific Change-of-Direction Speed Test With Striking Techniques in Elite Taekwondo Athletes: A Pilot Study},
series = {Frontiers in Physiology},
volume = {13},
journal = {Frontiers in Physiology},
publisher = {Frontiers},
address = {Lausanne, Schweiz},
issn = {1664-042X},
doi = {10.3389/fphys.2022.774546},
pages = {1 -- 15},
year = {2022},
abstract = {The purpose of this study was to examine the test-retest reliability, and convergent and discriminative validity of a new taekwondo-specific change-of-direction (COD) speed test with striking techniques (TST) in elite taekwondo athletes. Twenty (10 males and 10 females) elite (athletes who compete at national level) and top-elite (athletes who compete at national and international level) taekwondo athletes with an average training background of 8.9 ± 1.3 years of systematic taekwondo training participated in this study. During the two-week test-retest period, various generic performance tests measuring COD speed, balance, speed, and jump performance were carried out during the first week and as a retest during the second week. Three TST trials were conducted with each athlete and the best trial was used for further analyses. The relevant performance measure derived from the TST was the time with striking penalty (TST-TSP). TST-TSP performances amounted to 10.57 ± 1.08 s for males and 11.74 ± 1.34 s for females. The reliability analysis of the TST performance was conducted after logarithmic transformation, in order to address the problem of heteroscedasticity. In both groups, the TST demonstrated a high relative test-retest reliability (intraclass correlation coefficients and 90\% compatibility limits were 0.80 and 0.47 to 0.93, respectively). For absolute reliability, the TST's typical error of measurement (TEM), 90\% compatibility limits, and magnitudes were 4.6\%, 3.4 to 7.7, for males, and 5.4\%, 3.9 to 9.0, for females. The homogeneous sample of taekwondo athletes meant that the TST's TEM exceeded the usual smallest important change (SIC) with 0.2 effect size in the two groups. The new test showed mostly very large correlations with linear sprint speed (r = 0.71 to 0.85) and dynamic balance (r = -0.71 and -0.74), large correlations with COD speed (r = 0.57 to 0.60) and vertical jump performance (r = -0.50 to -0.65), and moderate correlations with horizontal jump performance (r = -0.34 to -0.45) and static balance (r = -0.39 to -0.44). Top-elite athletes showed better TST performances than elite counterparts. Receiver operating characteristic analysis indicated that the TST effectively discriminated between top-elite and elite taekwondo athletes. In conclusion, the TST is a valid, and sensitive test to evaluate the COD speed with taekwondo specific skills, and reliable when considering ICC and TEM. Although the usefulness of the TST is questioned to detect small performance changes in the present population, the TST can detect moderate changes in taekwondo-specific COD speed.},
language = {en}
}
@article{NobariMahmoudzadehKhaliliDencheZamoranoetal.2022,
author = {Nobari, Hadi and Mahmoudzadeh Khalili, Sara and Denche Zamorano, Angel Manuel and Bowman, Thomas G. and Granacher, Urs},
title = {Workload is associated with the occurrence of non-contact injuries in professional male soccer players: A pilot study},
series = {Frontiers in Psychology},
journal = {Frontiers in Psychology},
publisher = {Frontiers},
address = {Lausanne, Schweiz},
issn = {1664-1078},
doi = {10.3389/fpsyg.2022.925722},
pages = {1 -- 9},
year = {2022},
abstract = {Injuries in professional soccer are a significant concern for teams, and they are caused amongst others by high training load. This cohort study describes the relationship between workload parameters and the occurrence of non-contact injuries, during weeks with high and low workload in professional soccer players throughout the season. Twenty-one professional soccer players aged 28.3 ± 3.9 yrs. who competed in the Iranian Persian Gulf Pro League participated in this 48-week study. The external load was monitored using global positioning system (GPS, GPSPORTS Systems Pty Ltd) and the type of injury was documented daily by the team's medical staff. Odds ratio (OR) and relative risk (RR) were calculated for non-contact injuries for high- and low-load weeks according to acute (AW), chronic (CW), acute to chronic workload ratio (ACWR), and AW variation (Δ-Acute) values. By using Poisson distribution, the interval between previous and new injuries were estimated. Overall, 12 non-contact injuries occurred during high load and 9 during low load weeks. Based on the variables ACWR and Δ-AW, there was a significantly increased risk of sustaining non-contact injuries (p < 0.05) during high-load weeks for ACWR (OR: 4.67), and Δ-AW (OR: 4.07). Finally, the expected time between injuries was significantly shorter in high load weeks for ACWR [1.25 vs. 3.33, rate ratio time (RRT)] and Δ-AW (1.33 vs. 3.45, RRT) respectively, compared to low load weeks. The risk of sustaining injuries was significantly larger during high workload weeks for ACWR, and Δ-AW compared with low workload weeks. The observed high OR in high load weeks indicate that there is a significant relationship between workload and occurrence of non-contact injuries. The predicted time to new injuries is shorter in high load weeks compared to low load weeks. Therefore, the frequency of injuries is higher during high load weeks for ACWR and Δ-AW. ACWR and Δ-AW appear to be good indicators for estimating the injury risk, and the time interval between injuries.},
language = {en}
}
@article{BrahmsHeinzelRappetal.2022,
author = {Brahms, Markus and Heinzel, Stephan and Rapp, Michael Armin and M{\"u}ckstein, Marie and Hortob{\´a}gyi, Tibor and Stelzel, Christine and Granacher, Urs},
title = {The acute effects of mental fatigue on balance performance in healthy young and older adults - A systematic review and meta-analysis},
series = {Acta Psychologica},
volume = {225},
journal = {Acta Psychologica},
publisher = {Elsevier},
address = {Amsterdam},
issn = {1873-6297},
doi = {10.1016/j.actpsy.2022.103540},
pages = {1 -- 13},
year = {2022},
abstract = {Cognitive resources contribute to balance control. There is evidence that mental fatigue reduces cognitive resources and impairs balance performance, particularly in older adults and when balance tasks are complex, for example when trying to walk or stand while concurrently performing a secondary cognitive task. We conducted a systematic literature search in PubMed (MEDLINE), Web of Science and Google Scholar to identify eligible studies and performed a random effects meta-analysis to quantify the effects of experimentally induced mental fatigue on balance performance in healthy adults. Subgroup analyses were computed for age (healthy young vs. healthy older adults) and balance task complexity (balance tasks with high complexity vs. balance tasks with low complexity) to examine the moderating effects of these factors on fatigue-mediated balance performance. We identified 7 eligible studies with 9 study groups and 206 participants. Analysis revealed that performing a prolonged cognitive task had a small but significant effect (SMDwm = -0.38) on subsequent balance performance in healthy young and older adults. However, age- and task-related differences in balance responses to fatigue could not be confirmed statistically. Overall, aggregation of the available literature indicates that mental fatigue generally reduces balance in healthy adults. However, interactions between cognitive resource reduction, aging and balance task complexity remain elusive.},
language = {en}
}
@article{JafarnezhadgeroAmirzadehFatollahietal.2022,
author = {Jafarnezhadgero, Amir Ali and Amirzadeh, Nasrin and Fatollahi, Amir and Siahkouhian, Marefat and de Souza Castelo Oliveira, Anderson and Granacher, Urs},
title = {Effects of running on sand vs. stable ground on kinetics and muscle activities in individuals with over-pronated feet},
series = {Frontiers in physiology / Frontiers Research Foundation},
volume = {12},
journal = {Frontiers in physiology / Frontiers Research Foundation},
publisher = {Frontiers Research Foundation},
address = {Lausanne, Schweiz},
issn = {1664-042X},
doi = {10.3389/fphys.2021.822024},
pages = {1 -- 10},
year = {2022},
abstract = {Background: In terms of physiological and biomechanical characteristics, over-pronation of the feet has been associated with distinct muscle recruitment patterns and ground reaction forces during running. Objective: The aim of this study was to evaluate the effects of running on sand vs. stable ground on ground-reaction-forces (GRFs) and electromyographic (EMG) activity of lower limb muscles in individuals with over-pronated feet (OPF) compared with healthy controls. Methods: Thirty-three OPF individuals and 33 controls ran at preferred speed and in randomized-order over level-ground and sand. A force-plate was embedded in an 18-m runway to collect GRFs. Muscle activities were recorded using an EMG-system. Data were adjusted for surface-related differences in running speed. Results: Running on sand resulted in lower speed compared with stable ground running (p < 0.001; d = 0.83). Results demonstrated that running on sand produced higher tibialis anterior activity (p = 0.024; d = 0.28). Also, findings indicated larger loading rates (p = 0.004; d = 0.72) and greater vastus medialis (p < 0.001; d = 0.89) and rectus femoris (p = 0.001; d = 0.61) activities in OPF individuals. Controls but not OPF showed significantly lower gluteus-medius activity (p = 0.022; d = 0.63) when running on sand. Conclusion: Running on sand resulted in lower running speed and higher tibialis anterior activity during the loading phase. This may indicate alterations in neuromuscular demands in the distal part of the lower limbs when running on sand. In OPF individuals, higher loading rates together with greater quadriceps activity may constitute a proximal compensatory mechanism for distal surface instability.},
language = {en}
}
@article{PrieskeAboodardaSierraetal.2017,
author = {Prieske, Olaf and Aboodarda, Saied J. and Sierra, Jose A. Benitez and Behm, David G. and Granacher, Urs},
title = {Slower but not faster unilateral fatiguing knee extensions alter contralateral limb performance without impairment of maximal torque output},
series = {European journal of applied physiology},
volume = {117},
journal = {European journal of applied physiology},
publisher = {Springer},
address = {New York},
issn = {1439-6319},
doi = {10.1007/s00421-016-3524-6},
pages = {323 -- 334},
year = {2017},
abstract = {The purpose of the present study was to examine the effects of unilateral fatigue of the knee extensors at different movement velocities on neuromuscular performance in the fatigued and non-fatigued leg. Unilateral fatigue of the knee extensors was induced in 11 healthy young men (23.7 +/- 3.8 years) at slower (60A degrees/s; FAT60) and faster movement velocities (240A degrees/s; FAT240) using an isokinetic dynamometer. A resting control (CON) condition was included. The fatigue protocols consisted of five sets of 15 maximal concentric knee extensions using the dominant leg. Before and after fatigue, peak isokinetic torque (PIT) and time to PIT (TTP) of the knee extensors as well as electromyographic (EMG) activity of vastus medialis, vastus lateralis, and biceps femoris muscles were assessed at 60 and 240A degrees/s movement velocities in the fatigued and non-fatigued leg. In the fatigued leg, significantly greater PIT decrements were observed following FAT60 and FAT240 (11-19\%) compared to CON (3-4\%, p = .002, d = 2.3). Further, EMG activity increased in vastus lateralis and biceps femoris muscle following FAT240 only (8-28\%, 0.018 <= p <=.024, d = 1.8). In the non-fatigued leg, shorter TTP values were found after the FAT60 protocol (11-15\%, p = .023, d = 2.4). No significant changes were found for EMG data in the non-fatigued leg. The present study revealed that both slower and faster velocity fatiguing contractions failed to show any evidence of cross-over fatigue on PIT. However, unilateral knee extensor fatigue protocols conducted at slower movement velocities (i.e., 60A degrees/s) appear to modulate torque production on the non-fatigued side (evident in shorter TTP values).},
language = {en}
}
@article{BeijersbergenGranacherGaebleretal.2017,
author = {Beijersbergen, Chantal M. I. and Granacher, Urs and Gaebler, Martijn and DeVita, Paul and Hortobagyi, Tibor},
title = {Hip mechanics underlie lower extremity power training-induced increase in old adults' fast gait velocity},
series = {Gait \& posture},
volume = {52},
journal = {Gait \& posture},
publisher = {Elsevier},
address = {Clare},
issn = {0966-6362},
doi = {10.1016/j.gaitpost.2016.12.024},
pages = {338 -- 344},
year = {2017},
abstract = {Methods: As part of the Potsdam Gait Study (POGS), healthy old adults completed a no-intervention control period (69.1 +/- 4A yrs, n =14) or a power training program followed by detraining (72.9 +/- 5.4 yrs, n = 15).We measured isokinetic knee extensor and plantarflexor power and measured hip, knee and ankle kinetics at habitual, fast and standardized walking speeds. Results: Power training significantly increased isokinetic knee extensor power (25\%), plantarflexor power (43\%), and fast gait velocity (5.9\%). Gait mechanics underlying the improved fast gait velocity included increases in hip angular impulse (29\%) and H1 work (37\%) and no changes in positive knee (K2) and A2 work. Detraining further improved fast gait velocity (4.7\%) with reductions in H1(-35\%), and increases in K2 (36\%) and A2 (7\%). Conclusion: Power training increased fast gait velocity in healthy old adults by increasing the reliance on hip muscle function and thus further strengthened the age-related distal-to-proximal shift in muscle function. (C) 2016 Elsevier B.V. All rights reserved.},
language = {en}
}
@article{ChaouachiGranacherMakhloufetal.2017,
author = {Chaouachi, Mehdi and Granacher, Urs and Makhlouf, Issam and Hammami, Raouf and Behm, David G. and Chaouachi, Anis},
title = {Within Session Sequence of Balance and Plyometric Exercises Does Not Affect Training Adaptations with Youth Soccer Athletes},
series = {Journal of sports science \& medicine},
volume = {16},
journal = {Journal of sports science \& medicine},
publisher = {Department of Sports Medicine, Medical Faculty of Uludag University},
address = {Bursa},
issn = {1303-2968},
pages = {125 -- 136},
year = {2017},
abstract = {The integration of balance and plyometric training has been shown to provide significant improvements in sprint, jump, agility, and other performance measures in young athletes. It is not known if a specific within session balance and plyometric exercise sequence provides more effective training adaptations. The objective of the present study was to investigate the effects of using a sequence of alternating pairs of exercises versus a block (series) of all balance exercises followed by a block of plyometric exercises on components of physical fitness such as muscle strength, power, speed, agility, and balance. Twenty-six male adolescent soccer players ( 13.9 +/- 0.3 years) participated in an 8-week training program that either alternated individual balance (e. g., exercises on unstable surfaces) and plyometric (e. g., jumps, hops, rebounds) exercises or performed a block of balance exercises prior to a block of plyometric exercises within each training session. Pre- and post-training measures included proxies of strength, power, agility, sprint, and balance such as countermovement jumps, isometric back and knee extension strength, standing long jump, 10 and 30-m sprints, agility, standing stork, and Y-balance tests. Both groups exhibited significant, generally large magnitude (effect sizes) training improvements for all measures with mean performance increases of approximately > 30\%. There were no significant differences between the training groups over time. The results demonstrate the effectiveness of combining balance and plyometric exercises within a training session on components of physical fitness with young adolescents. The improved performance outcomes were not significantly influenced by the within session exercise sequence.},
language = {en}
}
@article{JafarnezhadgeroFakhriGranacher2021,
author = {Jafarnezhadgero, Amir Ali and Fakhri, Ehsan and Granacher, Urs},
title = {Effects of nail softness and stiffness with distance running shoes on ground reaction forces and vertical loading rates in male elite long-distance runners with pronated feet},
series = {BMC sports science, medicine \& rehabilitation},
volume = {13},
journal = {BMC sports science, medicine \& rehabilitation},
publisher = {BioMed Central},
address = {London},
issn = {2052-1847},
doi = {10.1186/s13102-021-00352-7},
pages = {1 -- 9},
year = {2021},
abstract = {Background To improve propulsion during running, athletes often wear spike shoes designed for training and/or competition. Running with spike shoes may cause pain and/or injuries. To address this problem, a modified spike shoe was tested. This study aimed to evaluate the effects of running with dual-versus single-stiffness spike running shoes on running mechanics in long-distance runners with pronated feet. Methods Sixteen male elite (national competitive level) runners (5000 or 10,000 m) aged 28.2 ± 2.5 years with pronated feet volunteered to participate in this study. To be included, participants had to have achieved personal best race times over 5- and/or 10-km races under 17 or 34 min during official running competitions. All participants were heel strikers and had a history of 11.2 ± 4.2 years of training. For the assessment of running kinetics, a force plate was imbedded into a walkway. Running kinematics were recorded using a Vicon-motion-capture system. Nike Zoom Rival shoes (Nike, Nike Zoom Rival, USA) were selected and adapted according to spike softness and stiffness. Participants ran at a constant speed of ~4.0 m/s across the walkway with both shoe conditions in randomized order. Six trials were recorded per condition. The main outcomes included peak ground reaction forces and their time-to-peak, average and instantaneous vertical loading rates, free moments, and peak ankle eversion angles. Results Paired t-tests revealed significantly lower lateral (p = 0.021, d = 0.95) and vertical (p = 0.010, d = 1.40) forces at heel contact during running with dual-stiffness spike shoes. Running with dual-stiffness spike shoes resulted in a significantly longer time-to-peak vertical (p = 0.004, d = 1.40) force at heel contact. The analysis revealed significantly lower average (p = 0.005, d = 0.46) and instantaneous (p = 0.021, d = 0.49) loading rates and peak negative free moment amplitudes (p = 0.016, d = 0.81) when running with dual-stiffness spike shoes. Finally, significantly lower peak ankle eversion angles were observed with dual-stiffness spike shoes (p < 0.001, d = 1.29). Conclusions Running in dual- compared with single-stiffness spike distance running shoes resulted in lower loading rates, free moment amplitudes, and peak ankle eversion angles of long-distance runners with pronated feet.},
language = {en}
}
@article{FuehnerGranacherGolleetal.2021,
author = {F{\"u}hner, Thea Heidi and Granacher, Urs and Golle, Kathleen and Kliegl, Reinhold},
title = {Age and sex effects in physical fitness components of 108,295 third graders including 515 primary schools and 9 cohorts},
series = {Scientific Reports},
volume = {11},
journal = {Scientific Reports},
publisher = {Nature Portfolio},
address = {Berlin},
issn = {2045-2322},
doi = {10.1038/s41598-021-97000-4},
pages = {1 -- 13},
year = {2021},
abstract = {Children's physical fitness development and related moderating effects of age and sex are well documented, especially boys' and girls' divergence during puberty. The situation might be different during prepuberty. As girls mature approximately two years earlier than boys, we tested a possible convergence of performance with five tests representing four components of physical fitness in a large sample of 108,295 eight-year old third-graders. Within this single prepubertal year of life and irrespective of the test, performance increased linearly with chronological age, and boys outperformed girls to a larger extent in tests requiring muscle mass for successful performance. Tests differed in the magnitude of age effects (gains), but there was no evidence for an interaction between age and sex. Moreover, "physical fitness" of schools correlated at r = 0.48 with their age effect which might imply that "fit schools" promote larger gains; expected secular trends from 2011 to 2019 were replicated.},
language = {en}
}
@article{WiesmeierDalinWehrleetal.2017,
author = {Wiesmeier, Isabella K. and Dalin, Daniela and Wehrle, Anja and Granacher, Urs and Muehlbauer, Thomas and Dietterle, J{\"o}rg and Weiller, Cornelius and Gollhofer, Albert and Maurer, Christoph},
title = {Balance training enhances vestibular function and reduces overactive proprioceptive feedback in elderly},
series = {Frontiers in aging neuroscience},
volume = {9},
journal = {Frontiers in aging neuroscience},
publisher = {Frontiers Research Foundation},
address = {Lausanne},
issn = {1663-4365},
doi = {10.3389/fnagi.2017.00273},
pages = {13},
year = {2017},
abstract = {Objectives: Postural control in elderly people is impaired by degradations of sensory, motor, and higher-level adaptive mechanisms. Here, we characterize the effects of a progressive balance training programon these postural control impairments using a brain network model based on system identification techniques. Methods and Material: We analyzed postural control of 35 healthy elderly subjects and compared findings to data from 35 healthy young volunteers. Eighteen elderly subjects performed a 10 week balance training conducted twice per week. Balance training was carried out in static and dynamic movement states, on support surfaces with different elastic compliances, under different visual conditions and motor tasks. Postural control was characterized by spontaneous sway and postural reactions to pseudorandom anterior-posterior tilts of the support surface. Data were interpreted using a parameter identification procedure based on a brain network model. Conclusion: Balance training reduced overactive proprioceptive feedback and restored vestibular orientation in elderly. Based on the assumption of a linear deterioration of postural control across the life span, the training effect can be extrapolated as a juvenescence of 10 years. This study points to a considerable benefit of a continuous balance training in elderly, even without any sensorimotor deficits.},
language = {en}
}
@misc{GranacherVoeller2018,
author = {Granacher, Urs and V{\"o}ller, Heinz},
title = {Gait speed is not magic, but is prognostically important in older patients},
series = {European journal of preventive cardiology : the official ESC journal for primary \& secondary cardiovascular prevention, rehabilitation and sports cardiology},
volume = {25},
journal = {European journal of preventive cardiology : the official ESC journal for primary \& secondary cardiovascular prevention, rehabilitation and sports cardiology},
number = {2},
publisher = {Sage Publ.},
address = {London},
issn = {2047-4873},
doi = {10.1177/2047487317744053},
pages = {209 -- 211},
year = {2018},
language = {en}
}
@article{SariatiZouhalHammamietal.2021,
author = {Sariati, Dorsaf and Zouhal, Hassane and Hammami, Raouf and Clark, Cain Craig Truman and Nebigh, Ammar and Chtara, Moktar and Hackney, Anthony C. and Souissi, Nizar and Granacher, Urs and Ben Ounis, Omar},
title = {Association Between Mental Imagery and Change of Direction Performance in Young Elite Soccer Players of Different Maturity Status},
series = {Frontiers in Psychology},
volume = {12},
journal = {Frontiers in Psychology},
publisher = {Frontiers Research Foundation},
address = {Lausanne, Schweiz},
issn = {1664-1078},
doi = {10.3389/fpsyg.2021.665508},
pages = {1 -- 9},
year = {2021},
abstract = {Previous studies have not considered the potential influence of maturity status on the relationship between mental imagery and change of direction (CoD) speed in youth soccer. Accordingly, this cross-sectional study examined the association between mental imagery and CoD performance in young elite soccer players of different maturity status. Forty young male soccer players, aged 10-17 years, were assigned into two groups according to their predicted age at peak height velocity (PHV) (Pre-PHV; n = 20 and Post-PHV; n = 20). Participants were evaluated on soccer-specific tests of CoD with (CoDBall-15m) and without (CoD-15m) the ball. Participants completed the movement imagery questionnaire (MIQ) with the three- dimensional structure, internal visual imagery (IVI), external visual imagery (EVI), as well as kinesthetic imagery (KI). The Post-PHV players achieved significantly better results than Pre-PHV in EVI (ES = 1.58, large; p < 0.001), CoD-15m (ES = 2.09, very large; p < 0.001) and CoDBall-15m (ES = 1.60, large; p < 0.001). Correlations were significantly different between maturity groups, where, for the pre-PHV group, a negative very large correlation was observed between CoDBall-15m and KI (r = -0.73, p = 0.001). For the post-PHV group, large negative correlations were observed between CoD-15m and IVI (r = -0.55, p = 0.011), EVI (r = -062, p = 0.003), and KI (r = -0.52, p = 0.020). A large negative correlation of CoDBall-15m with EVI (r = -0.55, p = 0.012) and very large correlation with KI (r = -0.79, p = 0.001) were also observed. This study provides evidence of the theoretical and practical use for the CoD tasks stimulus with imagery. We recommend that sport psychology specialists, coaches, and athletes integrated imagery for CoD tasks in pre-pubertal soccer players to further improve CoD related performance.},
language = {en}
}
@article{KasmiZouhalHammamietal.2021,
author = {Kasmi, Sofien and Zouhal, Hassane and Hammami, Raouf and Clark, Cain Craig Truman and Hackney, Anthony C. and Hammami, Amri and Chtara, Moktar and Chortane, Sabri Gaied and Ben Salah, Fatma Zohra and Granacher, Urs and Ben Ounis, Omar},
title = {The Effects of Eccentric and Plyometric Training Programs and Their Combination on Stability and the Functional Performance in the Post-ACL-Surgical Rehabilitation Period of Elite Female Athletes},
series = {Frontiers in physiology},
volume = {12},
journal = {Frontiers in physiology},
publisher = {Frontiers Research Foundation},
address = {Lausanne, Schweiz},
issn = {1664-042X},
doi = {10.3389/fphys.2021.688385},
pages = {1 -- 11},
year = {2021},
abstract = {Background: The standard method to treat physically active patients with anterior cruciate ligament (ACL) rupture is ligament reconstruction surgery. The rehabilitation training program is very important to improve functional performance in recreational athletes following ACL reconstruction. Objectives: The aims of this study were to compare the effects of three different training programs, eccentric training (ECC), plyometric training (PLYO), or combined eccentric and plyometric training (COMB), on dynamic balance (Y-BAL), the Lysholm Knee Scale (LKS), the return to sport index (RSI), and the leg symmetry index (LSI) for the single leg hop test for distance in elite female athletes after ACL surgery. Materials and Methods: Fourteen weeks after rehabilitation from surgery, 40 elite female athletes (20.3 ± 3.2 years), who had undergone an ACL reconstruction, participated in a short-term (6 weeks; two times a week) training study. All participants received the same rehabilitation protocol prior to the training study. Athletes were randomly assigned to three experimental groups, ECC (n = 10), PLYO (n = 10), and COMB (n = 10), and to a control group (CON: n = 10). Testing was conducted before and after the 6-week training programs and included the Y-BAL, LKS, and RSI. LSI was assessed after the 6-week training programs only. Results: Adherence rate was 100\% across all groups and no training or test-related injuries were reported. No significant between-group baseline differences (pre-6-week training) were observed for any of the parameters. Significant group-by-time interactions were found for Y-BAL (p < 0.001, ES = 1.73), LKS (p < 0.001, ES = 0.76), and RSI (p < 0.001, ES = 1.39). Contrast analysis demonstrated that COMB yielded significantly greater improvements in Y-BAL, LKS, and RSI (all p < 0.001), in addition to significantly better performances in LSI (all p < 0.001), than CON, PLYO, and ECC, respectively. Conclusion: In conclusion, combined (eccentric/plyometric) training seems to represent the most effective training method as it exerts positive effects on both stability and functional performance in the post-ACL-surgical rehabilitation period of elite female athletes.},
language = {en}
}
@article{WerfelliHammamiSelmietal.2021,
author = {Werfelli, Hanen and Hammami, Raouf and Selmi, Mohamed Amine and Selmi, Walid and Gabrilo, Goran and Clark, Cain C. T. and Duncan, Michael and Sekulic, Damir and Granacher, Urs and Rebai, Haithem},
title = {Acute Effects of Different Plyometric and Strength Exercises on Balance Performance in Youth Weightlifters},
series = {Frontiers in Physiology},
volume = {12},
journal = {Frontiers in Physiology},
publisher = {Frontiers Research Foundation},
address = {Lausanne},
issn = {1664-042X},
doi = {10.3389/fphys.2021.716981},
pages = {9},
year = {2021},
abstract = {Background: High-intensity muscle actions have the potential to temporarily improve the performance which has been denoted as postactivation performance enhancement. Objectives: This study determined the acute effects of different stretch-shortening (fast vs. low) and strength (dynamic vs. isometric) exercises executed during one training session on subsequent balance performance in youth weightlifters. Materials and Methods: Sixteen male and female young weightlifters, aged 11.3±0.6years, performed four strength exercise conditions in randomized order, including dynamic strength (DYN; 3 sets of 3 repetitions of 10 RM) and isometric strength exercises (ISOM; 3 sets of maintaining 3s of 10 RM of back-squat), as well as fast (FSSC; 3 sets of 3 repetitions of 20-cm drop-jumps) and slow (SSSC; 3 sets of 3 hurdle jumps over a 20-cm obstacle) stretch-shortening cycle protocols. Balance performance was tested before and after each of the four exercise conditions in bipedal stance on an unstable surface (i.e., BOSU ball with flat side facing up) using two dependent variables, i.e., center of pressure surface area (CoP SA) and velocity (CoP V). Results: There was a significant effect of time on CoP SA and CoP V [F(1,60)=54.37, d=1.88, p<0.0001; F(1,60)=9.07, d=0.77, p=0.003]. In addition, a statistically significant effect of condition on CoP SA and CoP V [F(3,60)=11.81, d=1.53, p<0.0001; F(3,60)=7.36, d=1.21, p=0.0003] was observed. Statistically significant condition-by-time interactions were found for the balance parameters CoP SA (p<0.003, d=0.54) and CoP V (p<0.002, d=0.70). Specific to contrast analysis, all specified hypotheses were tested and demonstrated that FSSC yielded significantly greater improvements than all other conditions in CoP SA and CoP V [p<0.0001 (d=1.55); p=0.0004 (d=1.19), respectively]. In addition, FSSC yielded significantly greater improvements compared with the two conditions for both balance parameters [p<0.0001 (d=2.03); p<0.0001 (d=1.45)]. Conclusion: Fast stretch-shortening cycle exercises appear to be more effective to improve short-term balance performance in young weightlifters. Due to the importance of balance for overall competitive achievement in weightlifting, it is recommended that young weightlifters implement dynamic plyometric exercises in the fast stretch-shortening cycle during the warm-up to improve their balance performance.},
language = {en}
}
@article{LesinskiPrieskeBeurskensetal.2017,
author = {Lesinski, Melanie and Prieske, Olaf and Beurskens, Rainer and Behm, David George and Granacher, Urs},
title = {Effects of Drop-height and Surface Instability on Jump Performance and Knee Kinematics},
series = {International journal of sports medicine},
volume = {39},
journal = {International journal of sports medicine},
number = {1},
publisher = {Thieme},
address = {Stuttgart},
issn = {0172-4622},
doi = {10.1055/s-0043-117610},
pages = {50 -- 57},
year = {2017},
abstract = {The purpose of this study was to examine the combined effects of drop-height and surface condition on drop jump (DJ) performance and knee joint kinematics. DJ performance, sagittal and frontal plane knee joint kinematics were measured in jump experienced young male and female adults during DJs on stable, unstable and highly unstable surfaces using different drop-heights (20, 40, 60 cm). Findings revealed impaired DJ performance (Δ5-16\%; p<0.05; 1.43≤d≤2.82), reduced knee valgus motion (Δ33-52\%; p<0.001; 2.70≤d≤3.59), and larger maximum knee flexion angles (Δ13-19\%; p<0.01; 1.74≤d≤1.75) when using higher (60 cm) compared to lower drop-heights (≤40 cm). Further, lower knee flexion angles and velocity were found (Δ8-16\%; p<0.01; 1.49≤d≤2.38) with increasing surface instability. When performing DJs from high (60 cm) compared to moderate drop-heights (40 cm) on highly unstable surfaces, higher knee flexion velocity and maximum knee valgus angles were found (Δ15-19\%; p<0.01; 1.50≤d≤1.53). No significant main and/or interaction effects were observed for the factor sex. In conclusion, knee motion strategies were modified by the factors 'drop-height' and/or 'surface instability'. The combination of high drop-heights (>40 cm) together with highly unstable surfaces should be used cautiously during plyometrics because this may increase the risk of injury due to higher knee valgus stress.},
language = {en}
}
@article{GaeblerBerberyanPrieskeetal.2021,
author = {G{\"a}bler, Martijn and Berberyan, Hermine S. and Prieske, Olaf and Elferink-Gemser, Marije Titia and Hortob{\´a}gyi, Tibor and Warnke, Torsten and Granacher, Urs},
title = {Strength Training Intensity and Volume Affect Performance of Young Kayakers/Canoeists},
series = {Frontiers in physiology},
volume = {12},
journal = {Frontiers in physiology},
publisher = {Frontiers Research Foundation},
address = {Lausanne, Schweiz},
issn = {1664-042X},
doi = {10.3389/fphys.2021.686744},
pages = {1 -- 10},
year = {2021},
abstract = {Purpose: The aim of this study was to compare the effects of moderate intensity, low volume (MILV) vs. low intensity, high volume (LIHV) strength training on sport-specific performance, measures of muscular fitness, and skeletal muscle mass in young kayakers and canoeists. Methods: Semi-elite young kayakers and canoeists (N = 40, 13 ± 0.8 years, 11 girls) performed either MILV (70-80\% 1-RM, 6-12 repetitions per set) or LIHV (30-40\% 1-RM, 60-120 repetitions per set) strength training for one season. Linear mixed-effects models were used to compare effects of training condition on changes over time in 250 and 2,000 m time trials, handgrip strength, underhand shot throw, average bench pull power over 2 min, and skeletal muscle mass. Both between- and within-subject designs were used for analysis. An alpha of 0.05 was used to determine statistical significance. Results: Between- and within-subject analyses showed that monthly changes were greater in LIHV vs. MILV for the 2,000 m time trial (between: 9.16 s, SE = 2.70, p < 0.01; within: 2,000 m: 13.90 s, SE = 5.02, p = 0.01) and bench pull average power (between: 0.021 W⋅kg-1, SE = 0.008, p = 0.02; within: 0.010 W⋅kg-1, SE = 0.009, p > 0.05). Training conditions did not affect other outcomes. Conclusion: Young sprint kayakers and canoeists benefit from LIHV more than MILV strength training in terms of 2,000 m performance and muscular endurance (i.e., 2 min bench pull power).},
language = {en}
}
@article{MuehlbauerGranacherBordeetal.2017,
author = {Muehlbauer, Thomas and Granacher, Urs and Borde, Ron and Hortobagyi, Tibor},
title = {Non-Discriminant Relationships between Leg Muscle Strength, Mass and Gait Performance in Healthy Young and Old Adults},
series = {Gerontology},
volume = {64},
journal = {Gerontology},
number = {1},
publisher = {Karger},
address = {Basel},
issn = {0304-324X},
doi = {10.1159/000480150},
pages = {11 -- 18},
year = {2017},
abstract = {Background: Gait speed declines with increasing age, but it is unclear if gait speed preferentially correlates with leg muscle strength or mass. Objective: We determined the relationship between gait speed and (1) leg muscle strength measured at 3 lower extremity joints and (2) leg lean tissue mass (LTM) in healthy young (age: 25 years, n = 20) and old (age: 70 years, n = 20) adults. Methods: Subjects were tested for maximal isokinetic hip, knee, and ankle extension torque, leg LTM by bioimpedance, and gait performance (i.e., gait speed, stride length) at preferred and maximal gait speeds. Results: We found no evidence for a preferential relationship between gait performance and leg muscle strength compared with gait performance and leg LTM in healthy young and old adults. In old adults, hip extensor strength only predicted habitual gait speed (R-2 = 0.29, p = 0.015), whereas ankle plantarflexion strength only predicted maximal gait speed and stride length (both R-2 = 0.40, p = 0.003). Conclusions: Gait speed did not preferentially correlate with leg muscle strength or leg LTM, favoring neither outcome for predicting mobility. Thus, we recommend that both leg muscle strength and leg LTM should be tested and trained complementarily. Further, hip and ankle extension torque predicted gait performance, and thus we recommend to test and train healthy old adults by functional integrated multiarticular rather than monoarticular lower extremity strength exercises.},
language = {en}
}
@article{JararnezhadgeroMamashliGranacher2021,
author = {Jararnezhadgero, AmirAli and Mamashli, Elaheh and Granacher, Urs},
title = {An Endurance-Dominated Exercise Program Improves Maximum Oxygen Consumption, Ground Reaction Forces, and Muscle Activities in Patients With Moderate Diabetic Neuropathy},
series = {Frontiers in physiology / Frontiers Research Foundation},
volume = {12},
journal = {Frontiers in physiology / Frontiers Research Foundation},
publisher = {Frontiers Research Foundation},
address = {Lausanne, Schweiz},
issn = {1664-042X},
doi = {10.3389/fphys.2021.654755},
pages = {1 -- 15},
year = {2021},
abstract = {Background: The prevalence of diabetes worldwide is predicted to increase from 2.8\% in 2000 to 4.4\% in 2030. Diabetic neuropathy (DN) is associated with damage to nerve glial cells, their axons, and endothelial cells leading to impaired function and mobility. Objective: We aimed to examine the effects of an endurance-dominated exercise program on maximum oxygen consumption (VO2max), ground reaction forces, and muscle activities during walking in patients with moderate DN. Methods: Sixty male and female individuals aged 45-65 years with DN were randomly assigned to an intervention (IG, n = 30) or a waiting control (CON, n = 30) group. The research protocol of this study was registered with the Local Clinical Trial Organization (IRCT20200201046326N1). IG conducted an endurance-dominated exercise program including exercises on a bike ergometer and gait therapy. The progressive intervention program lasted 12 weeks with three sessions per week, each 40-55 min. CON received the same treatment as IG after the post-tests. Pre- and post-training, VO2max was tested during a graded exercise test using spiroergometry. In addition, ground reaction forces and lower limbs muscle activities were recorded while walking at a constant speed of ∼1 m/s. Results: No statistically significant baseline between group differences was observed for all analyzed variables. Significant group-by-time interactions were found for VO2max (p < 0.001; d = 1.22). The post-hoc test revealed a significant increase in IG (p < 0.001; d = 1.88) but not CON. Significant group-by-time interactions were observed for peak lateral and vertical ground reaction forces during heel contact and peak vertical ground reaction force during push-off (p = 0.001-0.037; d = 0.56-1.53). For IG, post-hoc analyses showed decreases in peak lateral (p < 0.001; d = 1.33) and vertical (p = 0.004; d = 0.55) ground reaction forces during heel contact and increases in peak vertical ground reaction force during push-off (p < 0.001; d = 0.92). In terms of muscle activity, significant group-by-time interactions were found for vastus lateralis and gluteus medius during the loading phase and for vastus medialis during the mid-stance phase, and gastrocnemius medialis during the push-off phase (p = 0.001-0.044; d = 0.54-0.81). Post-hoc tests indicated significant intervention-related increases in vastus lateralis (p = 0.001; d = 1.08) and gluteus medius (p = 0.008; d = 0.67) during the loading phase and vastus medialis activity during mid-stance (p = 0.001; d = 0.86). In addition, post-hoc tests showed decreases in gastrocnemius medialis during the push-off phase in IG only (p < 0.001; d = 1.28). Conclusions: This study demonstrated that an endurance-dominated exercise program has the potential to improve VO2max and diabetes-related abnormal gait in patients with DN. The observed decreases in peak vertical ground reaction force during the heel contact of walking could be due to increased vastus lateralis and gluteus medius activities during the loading phase. Accordingly, we recommend to implement endurance-dominated exercise programs in type 2 diabetic patients because it is feasible, safe and effective by improving aerobic capacity and gait characteristics.},
language = {en}
}
@article{SariatiHammamiZouhaletal.2021,
author = {Sariati, Dorsaf and Hammami, Raouf and Zouhal, Hassane and Clark, Cain Craig Truman and Nebigh, Ammar and Chtara, Moktar and Chortane, Sabri Gaied and Hackney, Anthony C. and Souissi, Nizar and Granacher, Urs and Ben Ounis, Omar},
title = {Improvement of Physical Performance Following a 6 Week Change-of-Direction Training Program in Elite Youth Soccer Players of Different Maturity Levels},
series = {Frontiers in physiology},
volume = {12},
journal = {Frontiers in physiology},
editor = {Trecroci, Athos},
publisher = {Frontiers Research Foundation},
address = {Lausanne, Schweiz},
issn = {1664-042X},
doi = {10.3389/fphys.2021.668437},
pages = {1 -- 8},
year = {2021},
abstract = {Background: Change-of-direction (CoD) is a necessary physical ability of a field sport and may vary in youth players according to their maturation status. Objectives: The aim of this study is: to compare the effectiveness of a 6-week CoD training intervention on dynamic balance (CS-YBT), horizontal jump (5JT), speed (10 and 30-m linear sprint times), CoD with (15 m-CoD + B) and without (15 m-CoD) the ball, in youth male soccer players at different levels of maturity [pre- and post-peak height velocity (PHV)]. Materials and Methods: Thirty elite male youth soccer players aged 10-17 years from the Tunisian first division participated in this study. The players were divided into pre- (G1, n = 15) and post-PHV (G2, n = 15) groups. Both groups completed a similar 6-week training program with two sessions per week of four CoD exercises. All players completed the following tests before and after intervention: CS-YBT; 5 JT; 10, 30, and 15 m-CoD; and 15 m-CoD + B, and data were analyzed using ANCOVA. Results: All 30 players completed the study according to the study design and methodology. Adherence rate was 100\% across all groups, and no training or test-related injuries were reported. Pre-PHV and post-PHV groups showed significant amelioration post-intervention for all dependent variables (after test > before test; p < 0.01, d = 0.09-1.51). ANOVA revealed a significant group × time interaction only for CS-YBT (F = 4.45; p < 0.04; η2 = 0.14), 5JT (F = 6.39; p < 0.02; η2 = 0.18), and 15 m-CoD (F = 7.88; p < 0.01; η2 = 0.22). CS-YBT, 5JT, and 15 m-CoD improved significantly in the post-PHV group (+ 4.56\%, effect size = 1.51; + 4.51\%, effect size = 1.05; and -3.08\%, effect size = 0.51, respectively), more than the pre-PHV group (+ 2.77\%, effect size = 0.85; + 2.91\%, effect size = 0.54; and -1.56\%, effect size = 0.20, respectively). Conclusion: The CoD training program improved balance, horizontal jump, and CoD without the ball in male preadolescent and adolescent soccer players, and this improvement was greater in the post-PHV players. The maturity status of the athletes should be considered when programming CoD training for soccer players.},
language = {en}
}
@article{GranacherNobariRuivoAlvesetal.2020,
author = {Granacher, Urs and Nobari, Hadi and Ruivo Alves, Ana and Clemente, Filipe Manuel and P{\´e}rez-G{\´o}mez, Jorge and Clark, Cain Craig Truman and Zouhal, Hassane},
title = {Associations Between Variations in Accumulated Workload and Physiological Variables in Young Male Soccer Players Over the Course of a Season},
series = {Frontiers in physiology},
volume = {12},
journal = {Frontiers in physiology},
publisher = {Frontiers Research Foundation},
address = {Lausanne, Schweiz},
issn = {1664-042X},
doi = {10.3389/fphys.2021.638180},
pages = {1 -- 12},
year = {2020},
abstract = {This study sought to analyze the relationship between in-season training workload with changes in aerobic power (VO2max), maximum and resting heart rate (HRmax and HRrest), linear sprint medium (LSM), and short test (LSS), in soccer players younger than 16 years (under-16 soccer players). We additionally aimed to explain changes in fitness levels during the in-season through regression models, considering accumulated load, baseline levels, and peak height velocity (PHV) as predictors. Twenty-three male sub-elite soccer players aged 15.5 ± 0.2 years (PHV: 13.6 ± 0.4 years; body height: 172.7 ± 4.2 cm; body mass: 61.3 ± 5.6 kg; body fat: 13.7\% ± 3.9\%; VO2max: 48.4 ± 2.6 mL⋅kg-1⋅min-1), were tested three times across the season (i.e., early-season (EaS), mid-season (MiS), and end-season (EnS) for VO2max, HRmax, LSM, and LSS. Aerobic and speed variables gradually improved over the season and had a strong association with PHV. Moreover, the HRmax demonstrated improvements from EaS to EnS; however, this was more evident in the intermediate period (from EaS to MiS) and had a strong association with VO2max. Regression analysis showed significant predictions for VO2max [F(2, 20) = 8.18, p ≤ 0.001] with an R2 of 0.45. In conclusion, the meaningful variation of youth players' fitness levels can be observed across the season, and such changes can be partially explained by the load imposed.},
language = {en}
}
@article{MohammadiHilfikerJafarnezhadgeroetal.2017,
author = {Mohammadi, Vahid and Hilfiker, Roger and Jafarnezhadgero, Amir Ali and Jamialahmadi, Shima and Ardakani, Mohammad Karimizadeh and Granacher, Urs},
title = {Relationship between training-induced changes in the star excursion balance test and the Y balance test in young male athletes},
series = {Annals of applied sport science},
volume = {5},
journal = {Annals of applied sport science},
number = {3},
publisher = {Annals applied sport science},
address = {Tehran},
issn = {2322-4479},
doi = {10.29252/acadpub.aassjournal.5.3.31},
pages = {31 -- 38},
year = {2017},
abstract = {Background. Dynamic balance is often assessed in athletes using either the Star Excursion Balance Test (SEBT) or the Y Balance Test (YBT). There is evidence that the results for the three common directions are not comparable. Thus, the question is open to debate as to which instrument is better suited to measure training-induced changes over time. Objectives. The aim of this study is to compare the changes in the SEBT and the YBT, measured before and after six weeks of balance and strength exercise programmes in young and healthy athletes. Methods. A total of 30 young male athletes aged 15-17 years participated in this study and were involved in a six-week combined training, including balance and strength exercise. During pre-and post-training periods, the SEBT and YBT were conducted in random order. Results. The comparison between the changes in the SEBT and YBT with a paired sample T-test showed a significant increase in PM (p=0.001) and PL reach directions (p=0.000). No differences were observed in the A reach direction (p=0.38). Conclusion. the responsiveness levels of the SEBT and YBT are similar is valid. Also, because of higher effect size value in the anterior direction in YBT compared with SEBT, this balance test could possibly be preferred in this direction for postural control evaluation.},
language = {en}
}
@article{FernandezFernandezGranacherSanzRivasetal.2018,
author = {Fernandez-Fernandez, Jaime and Granacher, Urs and Sanz-Rivas, David and Sarabia Marin, Jose Manuel and Luis Hernandez-Davo, Jose and Moya, Manuel},
title = {Sequencing Effects of Neuromuscular Training on Physical Fitness in Youth Elite Tennis Players},
series = {Journal of strength and conditioning research : the research journal of the NSCA},
volume = {32},
journal = {Journal of strength and conditioning research : the research journal of the NSCA},
number = {3},
publisher = {Lippincott Williams \& Wilkins},
address = {Philadelphia},
issn = {1064-8011},
doi = {10.1519/JSC.0000000000002319},
pages = {849 -- 856},
year = {2018},
abstract = {Fernandez-Fernandez, J, Granacher, U, Sanz-Rivas, D, Sarabia Marin, JM, Hernandez-Davo, JL, and Moya, M. Sequencing effects of neuromuscular training on physical fitness in youth elite tennis players. J Strength Cond Res 32(3): 849-856, 2018-The aim of this study was to analyze the effects of a 5-week neuromuscular training (NMT) implemented before or after a tennis session in prepubertal players on selected components of physical fitness. Sixteen high-level tennis players with a mean age of 12.9 +/- 0.4 years participated in this study, and were assigned to either a training group performing NMT before tennis-specific training (BT; n = 8) or a group that conducted NMT after tennis-specific training (AT; n = 8). Pretest and posttest included: speed (5, 10, and 20 m); modified 5-0-5 agility test; countermovement jump (CMJ); overhead medicine ball throw (MBT); and serve velocity (SV). Results showed that the BT group achieved positive effects from pretest to posttest measures in speed (d = 0.52, 0.32, and 1.08 for 5, 10, and 20 m respectively), 5-0-5 (d = 0.22), CMJ (d = 0.29), MBT (d = 0.51), and SV (d = 0.32), whereas trivial (10 m, 20 m, CMJ, SV, and MBT) or negative effects (d = -0.19 and -0.24 for 5 m and 5-0-5, respectively) were reported for the AT group. The inclusion of an NMT session before the regular tennis training led to positive effects from pretest to posttest measures in performance-related variables (i.e., jump, sprint, change of direction capacity, as well as upper-body power), whereas conducting the same exercise sessions after the regular tennis training was not accompanied by the same improvements.},
language = {en}
}
@article{WeberPutaLesinskietal.2018,
author = {Weber, Stephanie and Puta, Christian and Lesinski, Melanie and Gabriel, Brunhild and Steidten, Thomas and B{\"a}r, Karl-J{\"u}rgen and Herbsleb, Marco and Granacher, Urs and Gabriel, Holger H. W.},
title = {Symptoms of anxiety and depression in young athletes using the hospital anxiety and depression scale},
series = {Frontiers in physiology},
volume = {9},
journal = {Frontiers in physiology},
publisher = {Frontiers Research Foundation},
address = {Lausanne},
issn = {1664-042X},
doi = {10.3389/fphys.2018.00182},
pages = {12},
year = {2018},
abstract = {Elite young athletes have to cope with multiple psychological demands such as training volume, mental and physical fatigue, spatial separation of family and friends or time management problems may lead to reduced mental and physical recovery. While normative data regarding symptoms of anxiety and depression for the general population is available (Hinz and Brahler, 2011), hardly any information exists for adolescents in general and young athletes in particular. Therefore, the aim of this study was to assess overall symptoms of anxiety and depression in young athletes as well as possible sex differences. The survey was carried out within the scope of the study "Resistance Training in Young Athletes" (KINGS-Study). Between August 2015 and September 2016, 326 young athletes aged (mean +/- SD) 14.3 +/- 1.6 years completed the Hospital Anxiety and Depression Scale (HAD Scale). Regarding the analysis of age on the anxiety and depression subscales, age groups were classified as follows: late childhood (12-14 years) and late adolescence (15-18 years). The participating young athletes were recruited from Olympic weight lifting, handball, judo, track and field athletics, boxing, soccer, gymnastics, ice speed skating, volleyball, and rowing. Anxiety and depression scores were (mean +/- SD) 4.3 +/- 3.0 and 2.8 +/- 2.9, respectively. In the subscale anxiety, 22 cases (6.7\%) showed subclinical scores and 11 cases (3.4\%) showed clinical relevant score values. When analyzing the depression subscale, 31 cases (9.5\%) showed subclinical score values and 12 cases (3.7\%) showed clinically important values. No significant differences were found between male and female athletes (p >= 0.05). No statistically significant differences in the HADS scores were found between male athletes of late childhood and late adolescents (p >= 0.05). To the best of our knowledge, this is the first report describing questionnaire based indicators of symptoms of anxiety and depression in young athletes. Our data implies the need for sports medical as well as sports psychiatric support for young athletes. In addition, our results demonstrated that the chronological classification concerning age did not influence HAD Scale outcomes. Future research should focus on sports medical and sports psychiatric interventional approaches with the goal to prevent anxiety and depression as well as teaching coping strategies to young athletes.},
language = {en}
}
@article{BriniBenAbderrahmanClarketal.2021,
author = {Brini, Seifeddine and Ben Abderrahman, Abderraouf and Clark, Cain C. T. and Zouita, Sghaeir and Hackney, Anthony C. and Govindasamy, Karuppasamy and Granacher, Urs and Zouhal, Hassane},
title = {Sex-specific effects of small-sided games in basketball on psychometric and physiological markers during Ramadan intermittent fasting},
series = {BMC Sports Science, Medicine and Rehabilitation},
volume = {13},
journal = {BMC Sports Science, Medicine and Rehabilitation},
publisher = {BioMed Central},
address = {London},
issn = {2052-1847},
doi = {10.1186/s13102-021-00285-1},
pages = {9},
year = {2021},
abstract = {Background: We assessed the effects of gender, in association with a four-week small-sided games (SSGs) training program, during Ramadan intermitting fasting (RIF) on changes in psychometric and physiological markers in professional male and female basketball players. Methods: Twenty-four professional basketball players from the first Tunisian (Tunisia) division participated in this study. The players were dichotomized by sex (males [GM = 12]; females [GF = 12]). Both groups completed a 4 weeks SSGs training program with 3 sessions per week. Psychometric (e.g., quality of sleep, fatigue, stress, and delayed onset of muscle soreness [DOMS]) and physiological parameters (e.g., heart rate frequency, blood lactate) were measured during the first week (baseline) and at the end of RIF (post-test). Results: Post hoc tests showed a significant increase in stress levels in both groups (GM [- 81.11\%; p < 0.001, d = 0.33, small]; GF [- 36,53\%; p = 0.001, d = 0.25, small]). Concerning physiological parameters, ANCOVA revealed significantly lower heart rates in favor of GM at post-test (1.70\%, d = 0.38, small, p = 0.002). Conclusions: Our results showed that SSGs training at the end of the RIF negatively impacted psychometric parameters of male and female basketball players. It can be concluded that there are sex-mediated effects of training during RIF in basketball players, and this should be considered by researchers and practitioners when programing training during RIF.},
language = {en}
}
@misc{RamirezCampilloAlvarezGarciaHermosoetal.2018,
author = {Ramirez-Campillo, Rodrigo and Alvarez, Cristian and Garcia-Hermoso, Antonio and Ramirez-Velez, Robinson and Gentil, Paulo and Asadi, Abbas and Chaabene, Helmi and Moran, Jason and Meylan, Cesar and Garcia-de-Alcaraz, Antonio and Sanchez-Sanchez, Javier and Nakamura, Fabio Y. and Granacher, Urs and Kraemer, William and Izquierdo, Mikel},
title = {Methodological characteristics and future directions for plyometric jump training research},
series = {Sports medicine},
volume = {48},
journal = {Sports medicine},
number = {5},
publisher = {Springer},
address = {Northcote},
issn = {0112-1642},
doi = {10.1007/s40279-018-0870-z},
pages = {1059 -- 1081},
year = {2018},
abstract = {Recently, there has been a proliferation of published articles on the effect of plyometric jump training, including several review articles and meta-analyses. However, these types of research articles are generally of narrow scope. Furthermore, methodological limitations among studies (e.g., a lack of active/passive control groups) prevent the generalization of results, and these factors need to be addressed by researchers. On that basis, the aims of this scoping review were to (1) characterize the main elements of plyometric jump training studies (e.g., training protocols) and (2) provide future directions for research. From 648 potentially relevant articles, 242 were eligible for inclusion in this review. The main issues identified related to an insufficient number of studies conducted in females, youths, and individual sports (~ 24.0, ~ 37.0, and ~ 12.0\% of overall studies, respectively); insufficient reporting of effect size values and training prescription (~ 34.0 and ~ 55.0\% of overall studies, respectively); and studies missing an active/passive control group and randomization (~ 40.0 and ~ 20.0\% of overall studies, respectively). Furthermore, plyometric jump training was often combined with other training methods and added to participants' daily training routines (~ 47.0 and ~ 39.0\% of overall studies, respectively), thus distorting conclusions on its independent effects. Additionally, most studies lasted no longer than 7 weeks. In future, researchers are advised to conduct plyometric training studies of high methodological quality (e.g., randomized controlled trials). More research is needed in females, youth, and individual sports. Finally, the identification of specific dose-response relationships following plyometric training is needed to specifically tailor intervention programs, particularly in the long term.},
language = {en}
}
@article{GranacherMuehlbauerGoestemeyeretal.2021,
author = {Granacher, Urs and Muehlbauer, Thomas and G{\"o}stemeyer, Gerd and Gruber, Stefanie and Gruber, Markus},
title = {The performance of balance exercises during daily tooth brushing is not sufficient to improve balance and muscle strength in healthy older adults},
series = {BMC Geriatrics},
volume = {21},
journal = {BMC Geriatrics},
publisher = {BioMed Central},
address = {London},
issn = {1471-2318},
doi = {10.1186/s12877-021-02206-w},
pages = {9},
year = {2021},
abstract = {Background High prevalence rates have been reported for physical inactivity, mobility limitations, and falls in older adults. Home-based exercise might be an adequate means to increase physical activity by improving health- (i.e., muscle strength) and skill-related components of physical fitness (i.e., balance), particularly in times of restricted physical activity due to pandemics. Objective The objective of this study was to examine the effects of home-based balance exercises conducted during daily tooth brushing on measures of balance and muscle strength in healthy older adults. Methods Fifty-one older adults were randomly assigned to a balance exercise group (n = 27; age: 65.1 ± 1.1 years) or a passive control group (n = 24; age: 66.2 ± 3.3 years). The intervention group conducted balance exercises over a period of eight weeks twice daily for three minutes each during their daily tooth brushing routine. Pre- and post-intervention, tests were included for the assessment of static steady-state balance (i.e., Romberg test), dynamic steady-state balance (i.e., 10-m single and dual-task walk test using a cognitive and motor interference task), proactive balance (i.e., Timed-Up-and-Go Test [TUG], Functional-Reach-Test [FRT]), and muscle strength (i.e., Chair-Rise-Test [CRT]). Results Irrespective of group, the statistical analysis revealed significant main effects for time (pre vs. post) for dual-task gait speed (p < .001, 1.12 ≤ d ≤ 2.65), TUG (p < .001, d = 1.17), FRT (p = .002, d = 0.92), and CRT (p = .002, d = 0.94) but not for single-task gait speed and for the Romberg-Test. No significant group × time interactions were found for any of the investigated variables. Conclusions The applied lifestyle balance training program conducted twice daily during tooth brushing routines appears not to be sufficient in terms of exercise dosage and difficulty level to enhance balance and muscle strength in healthy adults aged 60-72 years. Consequently, structured balance training programs using higher exercise dosages and/or more difficult balance tasks are recommended for older adults to improve balance and muscle strength.},
language = {en}
}
@article{PutaSteidtenBaumbachetal.2018,
author = {Puta, Christian and Steidten, Thomas and Baumbach, Philipp and Woehrl, Toni and May, Rico and Kellmann, Michael and Herbsleb, Marco and Gabriel, Brunhild and Weber, Stephanie and Granacher, Urs and Gabriel, Holger H. W.},
title = {Standardized assessment of resistance training-Induced subjective symptoms and objective signs of immunological stress responses in young athletes},
series = {Frontiers in physiology},
volume = {9},
journal = {Frontiers in physiology},
publisher = {Frontiers Research Foundation},
address = {Lausanne},
issn = {1664-042X},
doi = {10.3389/fphys.2018.00698},
pages = {11},
year = {2018},
abstract = {From a health and performance-related perspective, it is crucial to evaluate subjective symptoms and objective signs of acute training-induced immunological responses in young athletes. The limited number of available studies focused on immunological adaptations following aerobic training. Hardly any studies have been conducted on resistance-training induced stress responses. Therefore, the aim of this observational study was to investigate subjective symptoms and objective signs of immunological stress responses following resistance training in young athletes. Fourteen (7 females and 7 males) track and field athletes with a mean age of 16.4 years and without any symptoms of upper or lower respiratory tract infections participated in this study. Over a period of 7 days, subjective symptoms using the Acute Recovery and Stress Scale (ARSS) and objective signs of immunological responses using capillary blood markers were taken each morning and after the last training session. Differences between morning and evening sessions and associations between subjective and objective parameters were analyzed using generalized estimating equations (GEE). In post hoc analyses, daily change-scores of the ARSS dimensions were compared between participants and revealed specific changes in objective capillary blood samples. In the GEE models, recovery (ARSS) was characterized by a significant decrease while stress (ARSS) showed a significant increase between morning and evening-training sessions. A concomitant increase in white blood cell count (WBC), granulocytes (GRAN) and percentage shares of granulocytes (GRAN\%) was found between morning and evening sessions. Of note, percentage shares of lymphocytes (LYM\%) showed a significant decrease. Furthermore, using multivariate regression analyses, we identified that recovery was significantly associated with LYM\%, while stress was significantly associated with WBC and GRAN\%. Post hoc analyses revealed significantly larger increases in participants' stress dimensions who showed increases in GRAN\%. For recovery, significantly larger decreases were found in participants with decreases in LYM\% during recovery. More specifically, daily change-scores of the recovery and stress dimensions of the ARSS were associated with specific changes in objective immunological markers (GRAN\%, LYM\%) between morning and evening-training sessions. Our results indicate that changes of subjective symptoms of recovery and stress dimensions using the ARSS were associated with specific changes in objectively measured immunological markers.},
language = {en}
}
@article{ChaabeneLesinskiBehmetal.2020,
author = {Chaabene, Helmi and Lesinski, Melanie and Behm, David George and Granacher, Urs},
title = {Performance- and healthrelated benefits of youth resistance training},
series = {Sports Orthopaedics and Traumatology},
volume = {36},
journal = {Sports Orthopaedics and Traumatology},
number = {3},
publisher = {Elsevier},
address = {Amsterdam},
pages = {10},
year = {2020},
abstract = {Performance- and healthrelated benefits of yoThere is ample evidence that youth resistance training (RT) is safe, joyful, and effective for different markers of performance (e.g., muscle strength, power, linear sprint speed) and health (e.g., injury prevention). Accordingly, the first aim of this narrative review is to present and discuss the relevance of muscle strength for youth physical development. The second purpose is to report evidence on the effectiveness of RT on muscular fitness (muscle strength, power, muscle endurance), on movement skill performance and injury prevention in youth. There is evidence that RT is effective in enhancing measures of muscle fitness in children and adolescents, irrespective of sex. Additionally, numerous studies indicate that RT has positive effects on fundamental movement skills (e.g., jumping, running, throwing) in youth regardless of age, maturity, training status, and sex. Further, irrespective of age, sex, and training status, regular exposure to RT (e.g., plyometric training) decreases the risk of sustaining injuries in youth. This implies that RT should be a meaningful element of youths' exercise programming. This has been acknowledged by global (e.g., World Health Organization) and national (e.g., National Strength and Conditioning Association) health- and performance-related organizations which is why they recommended to perform RT as an integral part of weekly exercise programs to promote muscular strength, fundamental movement skills, and to resist injuries in youth.uth resistance training},
language = {en}
}
@article{RamachandranSinghRamirezCampilloetal.2021,
author = {Ramachandran, Akhilesh Kumar and Singh, Utkarsh and Ramirez-Campillo, Rodrigo and Clemente, Filipe Manuel and Afonso, Jos{\´e} and Granacher, Urs},
title = {Effects of Plyometric Jump Training on Balance Performance in Healthy Participants: A Systematic Review With Meta-Analysis / Effects of plyometric-jump training on balance performance in healthy individuals across the lifespan: A systematic review with meta-analysisist},
series = {Frontiers in Physiology},
volume = {12},
journal = {Frontiers in Physiology},
publisher = {Frontiers Research Foundation},
address = {Lausanne},
issn = {1664-042X},
pages = {22},
year = {2021},
abstract = {Postural balance represents a fundamental movement skill for the successful performance of everyday and sport-related activities. There is ample evidence on the effectiveness of balance training on balance performance in athletic and non-athletic population. However, less is known on potential transfer effects of other training types, such as plyometric jump training (PJT) on measures of balance. Given that PJT is a highly dynamic exercise mode with various forms of jump-landing tasks, high levels of postural control are needed to successfully perform PJT exercises. Accordingly, PJT has the potential to not only improve measures of muscle strength and power but also balance. To systematically review and synthetize evidence from randomized and non-randomized controlled trials regarding the effects of PJT on measures of balance in apparently healthy participants. Systematic literature searches were performed in the electronic databases PubMed, Web of Science, and SCOPUS. A PICOS approach was applied to define inclusion criteria, (i) apparently healthy participants, with no restrictions on their fitness level, sex, or age, (ii) a PJT program, (iii) active controls (any sport-related activity) or specific active controls (a specific exercise type such as balance training), (iv) assessment of dynamic, static balance pre- and post-PJT, (v) randomized controlled trials and controlled trials. The methodological quality of studies was assessed using the Physiotherapy Evidence Database (PEDro) scale. This meta-analysis was computed using the inverse variance random-effects model. The significance level was set at p <0.05. The initial search retrieved 8,251 plus 23 records identified through other sources. Forty-two articles met our inclusion criteria for qualitative and 38 for quantitative analysis (1,806 participants [990 males, 816 females], age range 9-63 years). PJT interventions lasted between 4 and 36 weeks. The median PEDro score was 6 and no study had low methodological quality (≤3). The analysis revealed significant small effects of PJT on overall (dynamic and static) balance (ES = 0.46; 95\% CI = 0.32-0.61; p < 0.001), dynamic (e.g., Y-balance test) balance (ES = 0.50; 95\% CI = 0.30-0.71; p < 0.001), and static (e.g., flamingo balance test) balance (ES = 0.49; 95\% CI = 0.31-0.67; p < 0.001). The moderator analyses revealed that sex and/or age did not moderate balance performance outcomes. When PJT was compared to specific active controls (i.e., participants undergoing balance training, whole body vibration training, resistance training), both PJT and alternative training methods showed similar effects on overall (dynamic and static) balance (p = 0.534). Specifically, when PJT was compared to balance training, both training types showed similar effects on overall (dynamic and static) balance (p = 0.514). Conclusion: Compared to active controls, PJT showed small effects on overall balance, dynamic and static balance. Additionally, PJT produced similar balance improvements compared to other training types (i.e., balance training). Although PJT is widely used in athletic and recreational sport settings to improve athletes' physical fitness (e.g., jumping; sprinting), our systematic review with meta-analysis is novel in as much as it indicates that PJT also improves balance performance. The observed PJT-related balance enhancements were irrespective of sex and participants' age. Therefore, PJT appears to be an adequate training regime to improve balance in both, athletic and recreational settings.},
language = {en}
}
@article{ChaabenePrieskeNegraetal.2018,
author = {Chaabene, Helmi and Prieske, Olaf and Negra, Yassine and Granacher, Urs},
title = {Change of direction speed},
series = {Sports medicine},
volume = {48},
journal = {Sports medicine},
number = {8},
publisher = {Springer},
address = {Northcote},
issn = {0112-1642},
doi = {10.1007/s40279-018-0907-3},
pages = {1773 -- 1779},
year = {2018},
abstract = {There is growing evidence that eccentric strength training appears to have benefits over traditional strength training (i.e., strength training with combined concentric and eccentric muscle actions) from muscular, neuromuscular, tendinous, and metabolic perspectives. Eccentric muscle strength is particularly needed to decelerate and stabilize the body during the braking phase of a jump exercise or during rapid changes of direction (CoD) tasks. However, surprisingly little research has been conducted to elucidate the effects of eccentric strength training or strength training with accentuated eccentric muscle actions on CoD speed performance. In this current opinion article, we present findings from cross-sectional studies on the relationship between measures of eccentric muscle strength and CoD speed performance. In addition, we summarize the few available studies on the effects of strength training with accentuated eccentric muscle actions on CoD speed performance in athletic populations. Finally, we propose strength training with accentuated eccentric muscle actions as a promising element in strength and conditioning programs of sports with high CoD speed demands. Our findings from five cross-sectional studies revealed statistically significant moderate-to large-sized correlations (r = 0.45-0.89) between measures of eccentric muscle strength and CoD speed performance in athletic populations. The identified three intervention studies were of limited methodological quality and reported small-to large-sized effects (d = 0.46-1.31) of strength training with accentuated eccentric muscle actions on CoD speed performance in athletes. With reference to the available but preliminary literature and from a performance-related point of view, we recommend strength and conditioning coaches to include strength training with accentuated eccentric muscle actions in training routines of sports with high CoD speed demands (e.g., soccer, handball, basketball, hockey) to enhance sport-specific performance. Future comparative studies are needed to deepen our knowledge of the effects of strength training with accentuated eccentric muscle actions on CoD speed performance in athletes.},
language = {en}
}
@article{TrautmannZhouBrahmsetal.2021,
author = {Trautmann, Justin and Zhou, Lin and Brahms, Clemens Markus and Tunca, Can and Ersoy, Cem and Granacher, Urs and Arnrich, Bert},
title = {TRIPOD},
series = {Data : open access ʻData in scienceʼ journal},
volume = {6},
journal = {Data : open access ʻData in scienceʼ journal},
number = {9},
publisher = {MDPI},
address = {Basel},
issn = {2306-5729},
doi = {10.3390/data6090095},
pages = {19},
year = {2021},
abstract = {Inertial measurement units (IMUs) enable easy to operate and low-cost data recording for gait analysis. When combined with treadmill walking, a large number of steps can be collected in a controlled environment without the need of a dedicated gait analysis laboratory. In order to evaluate existing and novel IMU-based gait analysis algorithms for treadmill walking, a reference dataset that includes IMU data as well as reliable ground truth measurements for multiple participants and walking speeds is needed. This article provides a reference dataset consisting of 15 healthy young adults who walked on a treadmill at three different speeds. Data were acquired using seven IMUs placed on the lower body, two different reference systems (Zebris FDMT-HQ and OptoGait), and two RGB cameras. Additionally, in order to validate an existing IMU-based gait analysis algorithm using the dataset, an adaptable modular data analysis pipeline was built. Our results show agreement between the pressure-sensitive Zebris and the photoelectric OptoGait system (r = 0.99), demonstrating the quality of our reference data. As a use case, the performance of an algorithm originally designed for overground walking was tested on treadmill data using the data pipeline. The accuracy of stride length and stride time estimations was comparable to that reported in other studies with overground data, indicating that the algorithm is equally applicable to treadmill data. The Python source code of the data pipeline is publicly available, and the dataset will be provided by the authors upon request, enabling future evaluations of IMU gait analysis algorithms without the need of recording new data.},
language = {en}
}
@article{SandauChaabeneGranacher2021,
author = {Sandau, Ingo and Chaabene, Helmi and Granacher, Urs},
title = {Concurrent validity of barbell force measured from video-based barbell kinematics during the snatch in male elite weightlifters},
series = {PLOS ONE / Public Library of Science},
volume = {16},
journal = {PLOS ONE / Public Library of Science},
number = {7},
publisher = {PLOS},
address = {San Francisco},
issn = {1932-6203},
doi = {10.1371/journal.pone.0254705},
pages = {11},
year = {2021},
abstract = {This study examined the concurrent validity of an inverse dynamic (force computed from barbell acceleration [reference method]) and a work-energy (force computed from work at the barbell [alternative method]) approach to measure the mean vertical barbell force during the snatch using kinematic data from video analysis. For this purpose, the acceleration phase of the snatch was analyzed in thirty male medal winners of the 2018 weightlifting World Championships (age: 25.2±3.1 years; body mass: 88.9±28.6 kg). Vertical barbell kinematics were measured using a custom-made 2D real-time video analysis software. Agreement between the two computational approaches was assessed using Bland-Altman analysis, Deming regression, and Pearson product-moment correlation. Further, principal component analysis in conjunction with multiple linear regression was used to assess whether individual differences related to the two approaches are due to the waveforms of the acceleration time-series data. Results indicated no mean difference (p > 0.05; d = -0.04) and an extremely large correlation (r = 0.99) between the two approaches. Despite the high agreement, the total error of individual differences was 8.2\% (163.0 N). The individual differences can be explained by a multiple linear regression model (R2adj = 0.86) on principal component scores from the principal component analysis of vertical barbell acceleration time-series waveforms. Findings from this study indicate that the individual errors of force measures can be associated with the inverse dynamic approach. This approach uses vertical barbell acceleration data from video analysis that is prone to error. Therefore, it is recommended to use the work-energy approach to compute mean vertical barbell force as this approach did not rely on vertical barbell acceleration.},
language = {en}
}
@misc{GaeblerPrieskeHortobagyietal.2018,
author = {Gaebler, Martijn and Prieske, Olaf and Hortobagyi, Tibor and Granacher, Urs},
title = {The effects of concurrent strength and endurance training on physical fitness and athletic performance in Youth},
series = {Frontiers in physiology},
volume = {9},
journal = {Frontiers in physiology},
publisher = {Frontiers Research Foundation},
address = {Lausanne},
issn = {1664-042X},
doi = {10.3389/fphys.2018.01057},
pages = {13},
year = {2018},
abstract = {Combining training of muscle strength and cardiorespiratory fitness within a training cycle could increase athletic performance more than single-mode training. However, the physiological effects produced by each training modality could also interfere with each other, improving athletic performance less than single-mode training. Because anthropometric, physiological, and biomechanical differences between young and adult athletes can affect the responses to exercise training, young athletes might respond differently to concurrent training (CT) compared with adults. Thus, the aim of the present systematic review with meta-analysis was to determine the effects of concurrent strength and endurance training on selected physical fitness components and athletic performance in youth. A systematic literature search of PubMed and Web of Science identified 886 records. The studies included in the analyses examined children (girls age 6-11 years, boys age 6-13 years) or adolescents (girls age 12-18 years, boys age 14-18 years), compared CT with single-mode endurance (ET) or strength training (ST), and reported at least one strength/power-(e.g., jump height), endurance-(e.g., peak. VO2, exercise economy), or performance-related (e.g., time trial) outcome. We calculated weighted standardized mean differences (SMDs). CT compared to ET produced small effects in favor of CT on athletic performance (n = 11 studies, SMD = 0.41, p = 0.04) and trivial effects on cardiorespiratory endurance (n = 4 studies, SMD = 0.04, p = 0.86) and exercise economy (n = 5 studies, SMD = 0.16, p = 0.49) in young athletes. A sub-analysis of chronological age revealed a trend toward larger effects of CT vs. ET on athletic performance in adolescents (SMD = 0.52) compared with children (SMD = 0.17). CT compared with ST had small effects in favor of CT on muscle power (n = 4 studies, SMD = 0.23, p = 0.04). In conclusion, CT is more effective than single-mode ET or ST in improving selected measures of physical fitness and athletic performance in youth. Specifically, CT compared with ET improved athletic performance in children and particularly adolescents. Finally, CT was more effective than ST in improving muscle power in youth.},
language = {en}
}
@article{HelmPrieskeMuehlbaueretal.2018,
author = {Helm, Norman and Prieske, Olaf and M{\"u}hlbauer, Thomas and Kr{\"u}ger, Tom and Chaabene, Helmi and Granacher, Urs},
title = {Validation of a new judo-specific ergometer system in male elite and sub-elite athletes},
series = {Journal of sports science \& medicine},
volume = {17},
journal = {Journal of sports science \& medicine},
number = {3},
publisher = {Department of Sports Medicine, Medical Faculty of Uludag University},
address = {Bursa},
issn = {1303-2968},
pages = {465 -- 474},
year = {2018},
abstract = {Our experimental approach included two studies to determine discriminative validity and test-retest reliability (study 1) as well as ecological validity (study 2) of a judo ergometer system while performing judo-specific movements. Sixteen elite (age: 23 +/- 3 years) and 11 sub-elite (age: 16 +/- 1 years) athletes participated in study 1 and 14 male sub-elite judo athletes participated in study 2. Discriminative validity and test-retest reliability of sport-specific parameters (mechanical work, maximal force) were assessed during pulling movements with and without tsukuri (kuzushi). Ecological validity of muscle activity was determined by performing pulling movements using the ergometer without tsukuri and during the same movements against an opponent. In both conditions, electromyographic activity of trunk (e.g., m. erector spinae) and upper limb muscles (e.g., m. biceps brachii) were assessed separately for the lifting and pulling arm. Elite athletes showed mostly better mechanical work, maximal force, and power (0.12 <= d <= 1.80) compared with sub-elite athletes. The receiver operating characteristic analysis revealed acceptable validity of the JERGo(C) system to discriminate athletes of different performance levels predominantly during kuzushi without tsukuri (area under the curve = 0.27-0.90). Moreover, small-to-medium discriminative validity was found to detect meaningful performance changes for mechanical work and maximal force. The JERGo(C) system showed small-to-high relative (ICC = 0.37-0.92) and absolute reliability (SEM = 10.8-18.8\%). Finally, our analyses revealed acceptable correlations (r = 0.41-0.88) between muscle activity during kuzushi performed with the JERGo(C) system compared with a judo opponent. Our findings indicate that the JERGo(C) system is a valid and reliable test instrument for the assessment and training of judo-specific pulling kinetics particularly during kuzushi movement without tsukuri.},
language = {en}
}
@misc{GebelLesinskiBehmetal.2018,
author = {Gebel, Arnd and Lesinski, Melanie and Behm, David George and Granacher, Urs},
title = {Effects and dose-response relationship of balance training on balance performance in Youth},
series = {Sports medicine},
volume = {48},
journal = {Sports medicine},
number = {9},
publisher = {Springer},
address = {Northcote},
issn = {0112-1642},
doi = {10.1007/s40279-018-0926-0},
pages = {2067 -- 2089},
year = {2018},
abstract = {Background Effects and dose-response relationships of balance training on measures of balance are well-documented for healthy young and old adults. However, this has not been systematically studied in youth. Objectives The objectives of this systematic review and meta-analysis were to quantify effects of balance training (BT) on measures of static and dynamic balance in healthy children and adolescents. Additionally, dose-response relations for BT modalities (e.g. training period, frequency, volume) were quantified through the analysis of controlled trials. Data Sources A computerized systematic literature search was conducted in the electronic databases PubMed and Web of Science from January 1986 until June 2017 to identify articles related to BT in healthy trained and untrained children and adolescents. Study Eligibility Criteria A systematic approach was used to evaluate articles that examined the effects of BT on balance outcomes in youth. Controlled trials with pre- and post-measures were included if they examined healthy youth with a mean age of 6-19 years and assessed at least one measure of balance (i.e. static/dynamic steady-state balance, reactive balance, proactive balance) with behavioural (e.g. time during single-leg stance) or biomechanical (e.g. centre of pressure displacements during single-leg stance) test methods. Study Appraisal and Synthesis Methods The included studies were coded for the following criteria: training modalities (i.e. training period, frequency, volume), balance outcomes (i.e. static and dynamic balance) as well as chronological age, sex (male vs. female), training status (trained vs. untrained), setting (school vs. club), and testing method (biomechanical vs. physical fitness test). Weighted mean standardized mean differences (SMDwm) were calculated using a random-effects model to compute overall intervention effects relative to active and passive control groups. Between-study heterogeneity was assessed using I 2 and chi(2) statistics. A multivariate random effects meta-regression was computed to explain the influence of key training modalities (i.e. training period, training frequency, total number of training sessions, duration of training sessions, and total duration of training per week) on the effectiveness of BT on measures of balance performance. Further, subgroup univariate analyses were computed for each training modality. Additionally, dose-response relationships were characterized independently by interpreting the modality specific magnitude of effect sizes. Methodological quality of the included studies was rated with the help of the Physiotherapy Evidence Database (PEDro) Scale. Results Overall, our literature search revealed 198 hits of which 17 studies were eligible for inclusion in this systematic review and meta-analysis. Irrespective of age, sex, training status, sport discipline and training method, moderate to large BT-related effects were found for measures of static (SMDwm = 0.71) and dynamic (SMDwm = 1.03) balance in youth. However, our subgroup analyses did not reveal any statistically significant effects of the moderator variables age, sex, training status, setting and testing method on overall balance (i.e. aggregation of static and dynamic balance). BT-related effects in adolescents were moderate to large for measures of static (SMDwm = 0.61) and dynamic (SMDwm = 0.86) balance. With regard to the dose-response relationships, findings from the multivariate random effects meta-regression revealed that none of the examined training modalities predicted the effects of BT on balance performance in adolescents (R-2 = 0.00). In addition, results from univariate analysis have to be interpreted with caution because training modalities were computed as single factors irrespective of potential between-modality interactions. For training period, 12 weeks of training achieved the largest effect (SMDwm = 1.40). For training frequency, the largest effect was found for two sessions per week (SMDwm = 1.29). For total number of training sessions, the largest effect was observed for 24-36 sessions (SMDwm = 1.58). For the modality duration of a single training session, 4-15 min reached the largest effect (SMDwm = 1.03). Finally, for the modality training per week, a total duration of 31-60 min per week (SMDwm = 1.33) provided the largest effects on overall balance in adolescents. Methodological quality of the studies was rated as moderate with a median PEDro score of 6.0. Limitations Dose-response relationships were calculated independently for training modalities (i.e. modality specific) and not interdependently. Training intensity was not considered for the calculation of dose-response relationships because the included studies did not report this training modality. Further, the number of included studies allowed the characterization of dose-response relationships in adolescents for overall balance only. In addition, our analyses revealed a considerable between-study heterogeneity (I-2 = 66-83\%). The results of this meta-analysis have to be interpreted with caution due to their preliminary status. Conclusions BT is a highly effective means to improve balance performance with moderate to large effects on static and dynamic balance in healthy youth irrespective of age, sex, training status, setting and testing method. The examined training modalities did not have a moderating effect on balance performance in healthy adolescents. Thus, we conclude that an additional but so far unidentified training modality may have a major effect on balance performance that was not assessed in our analysis. Training intensity could be a promising candidate. However, future studies are needed to find appropriate methods to assess BT intensity.},
language = {en}
}
@misc{GranacherPutaGabrieletal.2018,
author = {Granacher, Urs and Puta, Christian and Gabriel, Holger H. W. and Behm, David George and Arampatzis, Adamantios},
title = {Neuromuscular Training and Adaptations in Youth Athletes},
series = {Frontiers in physiology},
volume = {9},
journal = {Frontiers in physiology},
publisher = {Frontiers Research Foundation},
address = {Lausanne},
issn = {1664-042X},
doi = {10.3389/fphys.2018.01264},
pages = {5},
year = {2018},
language = {en}
}
@article{HammamiChaabeneKharratetal.2021,
author = {Hammami, Raouf and Chaabene, Helmi and Kharrat, Fatma and Werfelli, Hanen and Duncan, Michael and Rebai, Haithem and Granacher, Urs},
title = {Acute effects of different balance exercise types on selected measures of physical fitness in youth female volleyball players},
series = {BMC Sports Science, Medicine and Rehabilitation},
volume = {13},
journal = {BMC Sports Science, Medicine and Rehabilitation},
publisher = {BioMed Central},
address = {London},
issn = {1758-2555},
doi = {10.1186/s13102-021-00249-5},
pages = {8},
year = {2021},
abstract = {Background Earlier studies have shown that balance training (BT) has the potential to induce performance enhancements in selected components of physical fitness (i.e., balance, muscle strength, power, speed). While there is ample evidence on the long-term effects of BT on components of physical fitness in youth, less is known on the short-term or acute effects of single BT sessions on selected measures of physical fitness. Objective To examine the acute effects of different balance exercise types on balance, change-of-direction (CoD) speed, and jump performance in youth female volleyball players. Methods Eleven female players aged 14 years participated in this study. Three types of balance exercises (i.e., anterior, posterolateral, rotational type) were conducted in randomized order. For each exercise, 3 sets including 5 repetitions were performed. Before and after the performance of the balance exercises, participants were tested for their static balance (center of pressure surface area [CoP SA] and velocity [CoP V]) on foam and firm surfaces, CoD speed (T-Half test), and vertical jump height (countermovement jump [CMJ] height). A 3 (condition: anterior, mediolateral, rotational balance exercise type) × 2 (time: pre, post) analysis of variance was computed with repeated measures on time. Results Findings showed no significant condition × time interactions for all outcome measures (p > 0.05). However, there were small main effects of time for CoP SA on firm and foam surfaces (both d = 0.38; all p < 0.05) with no effect for CoP V on both surface conditions (p > 0.05). For CoD speed, findings showed a large main effect of time (d = 0.91; p < 0.001). However, for CMJ height, no main effect of time was observed (p > 0.05). Conclusions Overall, our results indicated small-to-large changes in balance and CoD speed performances but not in CMJ height in youth female volleyball players, regardless of the balance exercise type. Accordingly, it is recommended to regularly integrate balance exercises before the performance of sport-specific training to optimize performance development in youth female volleyball players.},
language = {en}
}
@article{LesinskiPrieskeBordeetal.2018,
author = {Lesinski, Melanie and Prieske, Olaf and Borde, Ron and Beurskens, Rainer and Granacher, Urs},
title = {Effects of Different Footwear Properties and Surface Instability on Neuromuscular Activity and Kinematics During Jumping},
series = {Journal of strength and conditioning research : the research journal of the NSCA},
volume = {32},
journal = {Journal of strength and conditioning research : the research journal of the NSCA},
number = {11},
publisher = {Lippincott Williams \& Wilkins},
address = {Philadelphia},
issn = {1064-8011},
doi = {10.1519/JSC.0000000000002556},
pages = {3246 -- 3257},
year = {2018},
abstract = {The purpose of this study was to examine sex-specific effects of different footwear properties vs. barefoot condition during the performance of drop jumps (DJs) on stable and unstable surfaces on measures of jump performance, electromyographic (EMG) activity, and knee joint kinematics. Drop jump performance, EMG activity of lower-extremity muscles, as well as sagittal and frontal knee joint kinematics were tested in 28 healthy male (n = 14) and female (n = 14) physically active sports science students (23 6 2 years) during the performance of DJs on stable and unstable surfaces using different footwear properties (elastic vs. minimal shoes) vs. barefoot condition. Analysis revealed a significantly lower jump height and performance index (Delta 7-12\%; p < 0.001; 2.22 <= d = 2.90) during DJs on unstable compared with stable surfaces. This was accompanied by lower thigh/shank muscle activities (Delta 11-28\%; p < 0.05; 0.99 <= d = 2.16) and knee flexion angles (Delta 5-8\%; p < 0.05; 1.02 <= d = 2.09). Furthermore, knee valgus angles during DJs were significantly lower when wearing shoes compared with barefoot condition (Delta 22-32\%; p < 0.01; 1.38 <= d = 3.31). Sex-specific analyses indicated higher knee flexion angles in females compared with males during DJs, irrespective of the examined surface and footwear conditions (Delta 29\%; p < 0.05; d = 0.92). Finally, hardly any significant footwear-surface interactions were detected. Our findings revealed that surface instability had an impact on DJ performance, thigh/shank muscle activity, and knee joint kinematics. In addition, the single factors "footwear" and "sex" modulated knee joint kinematics during DJs. However, hardly any significant interaction effects were found. Thus, additional footwear-related effects can be neglected when performing DJs during training on different surfaces.},
language = {en}
}
@article{GrabowYoungAlcocketal.2018,
author = {Grabow, Lena and Young, James D. and Alcock, Lynsey R. and Quigley, Patrick J. and Byrne, Jeannette M. and Granacher, Urs and Skarabot, Jakob and Behm, David George},
title = {Higher Quadriceps Roller Massage Forces Do Not Amplify Range-of-Motion Increases nor Impair Strength and Jump Performance},
series = {Journal of strength and conditioning research : the research journal of the NSCA},
volume = {32},
journal = {Journal of strength and conditioning research : the research journal of the NSCA},
number = {11},
publisher = {Lippincott Williams \& Wilkins},
address = {Philadelphia},
issn = {1064-8011},
doi = {10.1519/JSC.0000000000001906},
pages = {3059 -- 3069},
year = {2018},
abstract = {Grabow, L, Young, JD, Alcock, LR, Quigley, PJ, Byrne, JM, Granacher, U, Škarabot, J, and Behm, DG. Higher quadriceps roller massage forces do not amplify range-of-motion increases nor impair strength and jump performance. J Strength Cond Res 32(11): 3059-3069, 2018—Roller massage (RM) has been reported to increase range of motion (ROM) without subsequent performance decrements. However, the effects of different rolling forces have not been examined. The purpose of this study was to compare the effects of sham (RMsham), moderate (RMmod), and high (RMhigh) RM forces, calculated relative to the individuals' pain perception, on ROM, strength, and jump parameters. Sixteen healthy individuals (27 ± 4 years) participated in this study. The intervention involved three 60-second quadriceps RM bouts with RMlow (3.9/10 ± 0.64 rating of perceived pain [RPP]), RMmod (6.2/10 ± 0.64 RPP), and RMhigh (8.2/10 ± 0.44 RPP) pain conditions, respectively. A within-subject design was used to assess dependent variables (active and passive knee flexion ROM, single-leg drop jump [DJ] height, DJ contact time, DJ performance index, maximum voluntary isometric contraction [MVIC] force, and force produced in the first 200 milliseconds [F200] of the knee extensors and flexors). A 2-way repeated measures analysis of variance showed a main effect of testing time in active (p < 0.001, d = 2.54) and passive (p < 0.001, d = 3.22) ROM. Independent of the RM forces, active and passive ROM increased by 7.0\% (p = 0.03, d = 2.25) and 15.4\% (p < 0.001, d = 3.73) from premeasure to postmeasure, respectively. Drop jump and MVIC parameters were unaffected from pretest to posttest (p > 0.05, d = 0.33-0.84). Roller massage can be efficiently used to increase ROM without substantial pain and without subsequent performance impairments.},
language = {en}
}
@misc{MoranRamirezCampilloGranacher2018,
author = {Moran, Jason and Ramirez-Campillo, Rodrigo and Granacher, Urs},
title = {Effects of Jumping Exercise on Muscular Power in Older Adults},
series = {Sports medicine},
volume = {48},
journal = {Sports medicine},
number = {12},
publisher = {Springer},
address = {Northcote},
issn = {0112-1642},
doi = {10.1007/s40279-018-1002-5},
pages = {2843 -- 2857},
year = {2018},
abstract = {Background Jump training (JT) can be used to enhance the ability of skeletal muscle to exert maximal force in as short a time as possible. Despite its usefulness as a method of performance enhancement in athletes, only a small number of studies have investigated its effects on muscle power in older adults. Objectives The aims of this meta-analysis were to measure the effect of JT on muscular power in older adults (≥ 50 years), and to establish appropriate programming guidelines for this population. Data Sources The data sources utilised were Google Scholar, PubMed, and Microsoft Academic. Study Eligibility Criteria Studies were eligible for inclusion if they comprised JT interventions in healthy adults (≥ 50 years) who were free of any medical condition that could impair movement. Study Appraisal and Synthesis Methods The inverse variance random-effects model for meta-analyses was used because it allocates a proportionate weight to trials based on the size of their individual standard errors and facilitates analysis while accounting for heterogeneity across studies. Effect sizes (ESs), calculated from a measure of muscular power, were represented by the standardised mean difference and were presented alongside 95\% confidence intervals (CIs). Results Thirteen training groups across nine studies were included in this meta-analysis. The magnitude of the main effect was 'moderate' (0.66, 95\% CI 0.33, 0.98). ESs were larger in non-obese participants (body mass index [BMI] < 30 vs. ≥ 30 kg/m2; 1.03 [95\% CI 0.34, 1.73] vs. 0.53 [95\% CI - 0.03, 1.09]). Among the studies included in this review, just one reported an acute injury, which did not result in the participant ceasing their involvement. JT was more effective in programmes with more than one exercise (range 1-4 exercises; ES = 0.74 [95\% CI - 0.49, 1.96] vs. 0.53 [95\% CI 0.29, 0.78]), more than two sets per exercise (range 1-4 sets; ES = 0.91 [95\% CI 0.04, 1.77] vs. 0.68 [95\% CI 0.15, 1.21]), more than three jumps per set (range 1-14 jumps; ES = 1.02 [95\% CI 0.16, 1.87] vs. 0.53 [95\% CI - 0.03, 1.09]) and more than 25 jumps per session (range 6-200 jumps; ES = 0.88 [95\% CI 0.05, 1.70] vs. 0.49 [95\% CI 0.14, 0.83]). Conclusions JT is safe and effective in older adults. Practitioners should construct varied JT programmes that include more than one exercise and comprise more than two sets per exercise, more than three jumps per set, and 60 s of recovery between sets. An upper limit of three sets per exercise and ten jumps per set is recommended. Up to three training sessions per week can be performed.},
language = {en}
}
@article{HortobagyiUematsuSandersetal.2018,
author = {Hortobagyi, Tibor and Uematsu, Azusa and Sanders, Lianne and Kliegl, Reinhold and Tollar, Jozsef and Moraes, Renato and Granacher, Urs},
title = {Beam Walking to Assess Dynamic Balance in Health and Disease},
series = {Gerontology},
volume = {65},
journal = {Gerontology},
number = {4},
publisher = {Karger},
address = {Basel},
issn = {0304-324X},
doi = {10.1159/000493360},
pages = {332 -- 339},
year = {2018},
abstract = {Background: Dynamic balance keeps the vertical projection of the center of mass within the base of support while walking. Dynamic balance tests are used to predict the risks of falls and eventual falls. The psychometric properties of most dynamic balance tests are unsatisfactory and do not comprise an actual loss of balance while walking. Objectives: Using beam walking distance as a measure of dynamic balance, the BEAM consortium will determine the psychometric properties, lifespan and patient reference values, the relationship with selected "dynamic balance tests," and the accuracy of beam walking distance to predict falls. Methods: This cross-sectional observational study will examine healthy adults in 7 decades (n = 432) at 4 centers. Center 5 will examine patients (n = 100) diagnosed with Parkinson's disease, multiple sclerosis, stroke, and balance disorders. In test 1, all participants will be measured for demographics, medical history, muscle strength, gait, static balance, dynamic balance using beam walking under single (beam walking only) and dual task conditions (beam walking while concurrently performing an arithmetic task), and several cognitive functions. Patients and healthy participants age 50 years or older will be additionally measured for fear of falling, history of falls, miniBESTest, functional reach on a force platform, timed up and go, and reactive balance. All participants age 50 years or older will be recalled to report fear of falling and fall history 6 and 12 months after test 1. In test 2, seven to ten days after test 1, healthy young adults and age 50 years or older (n = 40) will be retested for reliability of beam walking performance. Conclusion: We expect to find that beam walking performance vis-{\`a}-vis the traditionally used balance outcomes predicts more accurately fall risks and falls. Clinical Trial Registration Number: NCT03532984.},
language = {en}
}
@article{PrieskeChaabenePutaetal.2019,
author = {Prieske, Olaf and Chaabene, Helmi and Puta, Christian and Behm, David George and B{\"u}sch, Dirk and Granacher, Urs},
title = {Effects of Drop Height on Jump Performance in Male and Female Elite Adolescent Handball Players},
series = {International journal of sports physiology and performance},
volume = {14},
journal = {International journal of sports physiology and performance},
number = {5},
publisher = {Human Kinetics Publ.},
address = {Champaign},
issn = {1555-0265},
doi = {10.1123/ijspp.2018-0482},
pages = {674 -- 680},
year = {2019},
abstract = {Purpose: To examine the effects of drop height on drop-jump (DJ) performance and on associations between DJ and horizontal-jump/sprint performances in adolescent athletes. Methods: Male (n = 119, 2.5 [0.6] y post-peak-height velocity) and female (n = 120, 2.5 [0.5] y post-peak-height velocity) adolescent handball players (national level) performed DJs in randomized order using 3 drop heights (20, 35, and 50 cm). DJ performance (jump height, reactive strength index [RSI]) was analyzed using the Optojump Next system. In addition, correlations were computed between DJ height and RSI with standing-long-jump and 20-m linear-sprint performances. Results: Statistical analyses revealed medium-size main effects of drop height for DJ height and RSI (P <.001, 0.63 <= d <= 0.71). Post hoc tests indicated larger DJ heights from 20 to 35 and 35 to 50 cm (P <=.031, 0.33 <= d <= 0.71) and better RSI from 20- to 35-cm drop height (P <.001, d = 0.77). No significant difference was found for RSI between 35- and 50-cm drop height. Irrespective of drop height, associations of DJ height and RSI were small with 5-m-split time (-.27 <= r <=.05), medium with 10-m-split time (-.44 <= r <=.14), and medium to large with 20-m sprint time and standing-long-jump distance (-.57 <= r <=.22). Conclusions: The present findings indicate that, irrespective of sex, 35-cm drop heights are best suited to induce rapid and powerful DJ performance (ie, RSI) during reactive strength training in elite adolescent handball players. Moreover, training-related gains in DJ performance may at least partly translate to gains in horizontal jump and longer sprint distances (ie, >= 20-m) and/or vice versa in male and female elite adolescent athletes, irrespective of drop height.},
language = {en}
}
@article{ZouitaZouhalFerchichietal.2020,
author = {Zouita, Sghaier and Zouhal, Hassane and Ferchichi, Habiba and Paillard, Thierry and Dziri, Catherine and Hackney, Anthony C. and Laher, Ismail and Granacher, Urs and Ben Moussa Zouita, Amira},
title = {Effects of Combined Balance and Strength Training on Measures of Balance and Muscle Strength in Older Women With a History of Falls},
series = {Frontiers in Physiology},
volume = {11},
journal = {Frontiers in Physiology},
publisher = {Frontiers Research Foundation},
address = {Lausanne},
issn = {1664-042X},
doi = {10.3389/fphys.2020.619016},
pages = {13},
year = {2020},
abstract = {Objective: We investigated the effects of combined balance and strength training on measures of balance and muscle strength in older women with a history of falls. Methods: Twenty-seven older women aged 70.4 ± 4.1 years (age range: 65 to 75 years) were randomly allocated to either an intervention (IG, n = 12) or an active control (CG, n = 15) group. The IG completed 8 weeks combined balance and strength training program with three sessions per week including visual biofeedback using force plates. The CG received physical therapy and gait training at a rehabilitation center. Training volumes were similar between the groups. Pre and post training, tests were applied for the assessment of muscle strength (weight-bearing squat [WBS] by measuring the percentage of body mass borne by each leg at different knee flexions [0°, 30°, 60°, and 90°], sit-to-stand test [STS]), and balance. Balance tests used the modified clinical test of sensory interaction (mCTSIB) with eyes closed (EC) and opened (EO), on stable (firm) and unstable (foam) surfaces as well as spatial parameters of gait such as step width and length (cm) and walking speed (cm/s). Results: Significant group × time interactions were found for different degrees of knee flexion during WBS (0.0001 < p < 0.013, 0.441 < d < 0.762). Post hoc tests revealed significant pre-to-post improvements for both legs and for all degrees of flexion (0.0001 < p < 0.002, 0.697 < d < 1.875) for IG compared to CG. Significant group × time interactions were found for firm EO, foam EO, firm EC, and foam EC (0.006 < p < 0.029; 0.302 < d < 0.518). Post hoc tests showed significant pre-to-post improvements for both legs and for all degrees of oscillations (0.0001 < p < 0.004, 0.753 < d < 2.097) for IG compared to CG. This study indicates that combined balance and strength training improved percentage distribution of body weight between legs at different conditions of knee flexion (0°, 30°, 60°, and 90°) and also decreased the sway oscillation on a firm surface with eyes closed, and on foam surface (with eyes opened or closed) in the IG. Conclusion: The higher positive effects of training seen in standing balance tests, compared with dynamic tests, suggests that balance training exercises including lateral, forward, and backward exercises improved static balance to a greater extent in older women.},
language = {en}
}
@article{ZinkeGebelGranacheretal.2019,
author = {Zinke, Fridolin and Gebel, Arnd and Granacher, Urs and Prieske, Olaf},
title = {Acute Effects of Short-Term Local Tendon Vibration on Plantar Flexor Torque, Muscle Contractile Properties, Neuromuscular and Brain Activity in Young Athletes},
series = {Journal of sports science \& medicine},
volume = {18},
journal = {Journal of sports science \& medicine},
number = {2},
publisher = {Department of Sports Medicine, Medical Faculty of Uludag University},
address = {Bursa},
issn = {1303-2968},
pages = {327 -- 336},
year = {2019},
abstract = {The purpose of this study was to examine the acute effects of short-term Achilles tendon vibration on plantar flexor torque, twitch contractile properties as well as muscle and cortical activity in young athletes. Eleven female elite soccer players aged 15.6 +/- 0.5 years participated in this study. Three different conditions were applied in randomized order: Achilles tendon vibration (80 Hz) for 30 and 300 s, and a passive control condition (300 s). Tests at baseline and following conditions included the assessment of peak plantar flexor torque during maximum voluntary contraction, electrically evoked muscle twitches (e.g., potentiated twitch peak torque [PT]), and electromyographic (EMG) activity of the plantar flexors. Additionally, electroencephalographic (EEG) activity of the primary motor and somatosensory cortex were assessed during a submaximal dynamic concentric-eccentric plantar flexion exercise using an elastic rubber band. Large-sized main effects of condition were found for EEG absolute alpha-1 and beta-1 band power (p <= 0.011; 1.5 <= d <= 2.6). Post-hoc tests indicated that alpha-1 power was significantly lower at 30 and 300 s (p = 0.009; d = 0.8) and beta-1 power significantly lower at 300 s (p < 0.001; d = 0.2) compared to control condition. No significant effect of condition was found for peak plantar flexor torque, electrical evoked muscle twitches, and EMG activity. In conclusion, short-term local Achilles tendon vibration induced lower brain activity (i.e., alpha-1 and beta-1 band power) but did not affect lower limb peak torque, twitch contractile properties, and muscle activity. Lower brain activity following short-term local Achilles tendon vibration may indicate improved cortical function during a submaximal dynamic exercise in female young soccer players.},
language = {en}
}
@article{ChaabeneNegraCapranicaetal.2019,
author = {Chaabene, Helmi and Negra, Yassine and Capranica, Laura and Prieske, Olaf and Granacher, Urs},
title = {A Needs Analysis of Karate Kumite With Recommendations for Performance Testing and Training},
series = {Strength and conditioning journal},
volume = {41},
journal = {Strength and conditioning journal},
number = {3},
publisher = {Lippincott Williams \& Wilkins},
address = {Philadelphia},
issn = {1524-1602},
doi = {10.1519/SSC.0000000000000445},
pages = {35 -- 46},
year = {2019},
abstract = {An effective training program needs to be customized to the specific demands of the redpective sport. Therefore, it is important to conduct a needs analysis to gain information on the unique characteristics of the sport. The objectives of thes review were (A) to conduct a systematic needs analysis of karate kumite and (B) to provide practical recommendations for sport-specific performance testing and training of karate kumite athletes.},
language = {en}
}
@article{PavillonTournyBenAbderrahmanetal.2020,
author = {Pavillon, Thomas and Tourny, Claire and Ben Abderrahman, Abderraouf and Salhi, Iyed and Zouita, Sghaeir and Rouissi, Mehdi and Hackney, Anthony C. and Granacher, Urs and Zouhal, Hassane},
title = {Sprint and jump performances in highly trained young soccer players of different chronological age},
series = {Journal of Exercise Science \& Fitness},
volume = {19},
journal = {Journal of Exercise Science \& Fitness},
number = {2},
publisher = {Elsevier},
address = {Singapore},
issn = {1728-869x},
doi = {10.1016/j.jesf.2020.10.003},
pages = {81 -- 90},
year = {2020},
abstract = {Objective The aim of this study was to examine the effects of two different sprint-training regimes on sprint and jump performances according to age in elite young male soccer players over the course of one soccer season. Methods Players were randomly assigned to two training groups. Group 1 performed systematic change-of-direction sprints (CODST, U19 [n = 9], U17 [n = 9], U15 [n = 10]) while group 2 conducted systematic linear sprints (LST, U19 [n = 9], U17 [n = 9], U15 [n = 9]). Training volumes were similar between groups (40 sprints per week x 30 weeks = 1200 sprints per season). Pre and post training, all players performed tests for the assessment of linear and slalom sprint speed (5-m and 10-m), countermovement jump, and maximal aerobic speed performance. Results For all physical fitness measures, the baseline-adjusted means data (ANCOVA) across the age groups showed no significant differences between LST and CODST at post (0.061 < p < 0.995; 0.0017 < d < 1.01). The analyses of baseline-adjusted means for all physical fitness measures for U15, U17, and U19 (LST vs. CODST) revealed no significant differences between LST and CODST for U15 (0.213 < p < 0.917; 0.001 < d < 0.087), U17 (0.132 < p < 0.976; 0.001 < d < 0.310), and U19 (0.300 < p < 0.999; 0.001 < d < 0.049) at post. Conclusions The results from this study showed that both, LST and CODST induced significant changes in the sprint, lower limbs power, and aerobic performances in young elite soccer players. Since no significant differences were observed between LST and CODST, the observed changes are most likely due to training and/or maturation. Therefore, more research is needed to elucidate whether CODST, LST or a combination of both is beneficial for youth soccer athletes' performance development.},
language = {en}
}
@article{NevillNegraMyersetal.2021,
author = {Nevill, Alan M. and Negra, Yassine and Myers, Tony D. and Duncan, Michael J. and Chaabene, Helmi and Granacher, Urs},
title = {Are Early or Late Maturers Likely to Be Fitter in the General Population?},
series = {International Journal of Environmental Research and Public Health},
volume = {18},
journal = {International Journal of Environmental Research and Public Health},
number = {2},
publisher = {MDPI},
address = {Basel},
issn = {1660-4601},
doi = {10.3390/ijerph18020497},
pages = {16},
year = {2021},
abstract = {The present study aims to identify the optimal body-size/shape and maturity characteristics associated with superior fitness test performances having controlled for body-size, sex, and chronological-age differences. The sample consisted of 597 Tunisian children (396 boys and 201 girls) aged 8 to 15 years. Three sprint speeds recorded at 10, 20 and 30 m; two vertical and two horizontal jump tests; a change-of-direction and a handgrip-strength tests, were assessed during physical-education classes. Allometric modelling was used to identify the benefit of being an early or late maturer. Findings showed that being tall and light is the ideal shape to be successful at most physical fitness tests, but the height-to-weight "shape" ratio seems to be test-dependent. Having controlled for body-size/shape, sex, and chronological age, the model identified maturity-offset as an additional predictor. Boys who go earlier/younger through peak-height-velocity (PHV) outperform those who go at a later/older age. However, most of the girls' physical-fitness tests peaked at the age at PHV and decline thereafter. Girls whose age at PHV was near the middle of the age range would appear to have an advantage compared to early or late maturers. These findings have important implications for talent scouts and coaches wishing to recruit children into their sports/athletic clubs.},
language = {en}
}
@article{CoppalleRaveMoranetal.2021,
author = {Coppalle, Sullivan and Rav{\´e}, Guillaume and Moran, Jason and Salhi, Iyed and Ben Abderrahman, Abderraouf and Zouita, Sghaeir and Granacher, Urs and Zouhal, Hassane},
title = {Internal and External Training Load in Under-19 versus Professional Soccer Players during the In-Season Period},
series = {International Journal of Environmental Research and Public Health},
volume = {18},
journal = {International Journal of Environmental Research and Public Health},
number = {2},
publisher = {MDPI AG},
address = {Basel},
issn = {1660-4601},
doi = {10.3390/ijerph18020558},
pages = {10},
year = {2021},
abstract = {This study aimed to compare the training load of a professional under-19 soccer team (U-19) to that of an elite adult team (EAT), from the same club, during the in-season period. Thirty-nine healthy soccer players were involved (EAT [n = 20]; U-19 [n = 19]) in the study which spanned four weeks. Training load (TL) was monitored as external TL, using a global positioning system (GPS), and internal TL, using a rating of perceived exertion (RPE). TL data were recorded after each training session. During soccer matches, players' RPEs were recorded. The internal TL was quantified daily by means of the session rating of perceived exertion (session-RPE) using Borg's 0-10 scale. For GPS data, the selected running speed intensities (over 0.5 s time intervals) were 12-15.9 km/h; 16-19.9 km/h; 20-24.9 km/h; >25 km/h (sprint). Distances covered between 16 and 19.9 km/h, > 20 km/h and >25 km/h were significantly higher in U-19 compared to EAT over the course of the study (p = 0.023, d = 0.243, small; p = 0.016, d = 0.298, small; and p = 0.001, d = 0.564, small, respectively). EAT players performed significantly fewer sprints per week compared to U-19 players (p = 0.002, d = 0.526, small). RPE was significantly higher in U-19 compared to EAT (p = 0.001, d = 0.188, trivial). The external and internal measures of TL were significantly higher in the U-19 group compared to the EAT soccer players. In conclusion, the results obtained show that the training load is greater in U19 compared to EAT.},
language = {en}
}
@article{MadadiShadJafarnezhadgeroZagoetal.2019,
author = {Madadi-Shad, Morteza and Jafarnezhadgero, Amir Ali and Zago, Matteo and Granacher, Urs},
title = {Effects of varus knee alignment on gait biomechanics and lower limb muscle activity in boys},
series = {Gait \& posture},
volume = {72},
journal = {Gait \& posture},
publisher = {Elsevier},
address = {Amsterdam},
issn = {0966-6362},
doi = {10.1016/j.gaitpost.2019.05.030},
pages = {69 -- 75},
year = {2019},
abstract = {Background: There is evidence that frontal plane lower limb malalignment (e.g., genu varus) is a risk factor for knee osteoarthritis development. However, only scarce information is available on gait biomechanics and muscle activity in boys with genu varus. Research question: To examine the effects of knee varus alignment on lower limb kinematics, kinetics and muscular activity during walking at self-selected speed in boys with genu varus versus healthy age-matched controls. Methods: Thirty-six boys were enrolled in this study and divided into a group of boys with genu varus (n = 18; age: 11.66 +/- 1.64 years) and healthy controls (n = 18; age: 11.44 +/- 1.78 years). Three-dimensional kinematics, ground reaction forces, loading rates, impulses and free moments of both limbs were recorded during five walking trials at self-selected speed. Surface electromyography was recorded for rectus femoris and vastus lateralis/medialis muscles. Results: No significant between-group differences were found for gait speed. Participants in the genu varus group versus controls showed larger peak knee flexion (p = 0.030; d = 0.77), peak knee adduction (p < 0.001; d = 1.63), and peak ankle eversion angles (p < 0.001; d = 2.06). Significantly higher peak ground reaction forces were found at heel contact (vertical [p = 0.002; d = 1.16] and posterior [p < 0.001; d = 1.63] components) and at push off (vertical [p = 0.010; d = 0.93] and anterior [p < 0.001; d = 1.34] components) for genu varus versus controls. Peak medial ground reaction force (p = 0.032; d = 0.76), vertical loading rate (p < 0.001; d = 1.52), anterior-posterior impulse (p = 0.011; d = 0.92), and peak negative free moment (p = 0.030; d = 0.77) were significantly higher in genu varus. Finally, time to reach peak forces was significantly shorter in genu varus boys compared with healthy controls (p < 0.01; d = 0.73-1.60). The genu varus group showed higher activities in vastus lateralis (p < 0.001; d = 1.82) and vastus medialis (p = 0.013; d = 0.90) during the loading phase of walking. Significance: Our study revealed genu varus specific gait characteristics and muscle activities. Greater knee adduction angle in genu varus boys may increase the load on the medial compartment of the knee joint. The observed characteristics in lower limb biomechanics and muscle activity could play a role in the early development of knee osteoarthritis in genu varus boys.},
language = {en}
}
@article{ElAshkerChaabeneNegraetal.2018,
author = {El-Ashker, Said and Chaabene, Helmi and Negra, Yassine and Prieske, Olaf and Granacher, Urs},
title = {Cardio-Respiratory Endurance Responses Following a Simulated 3 x 3 Minutes Amateur Boxing Contest in Elite Level Boxers},
series = {Sports},
volume = {6},
journal = {Sports},
number = {4},
publisher = {MDPI},
address = {Basel},
issn = {2075-4663},
doi = {10.3390/sports6040119},
pages = {8},
year = {2018},
abstract = {This study aimed at examining physiological responses (i.e., oxygen uptake [VO2] and heart rate [HR]) to a semi-contact 3 x 3-min format, amateur boxing combat simulation in elite level male boxers. Eleven boxers aged 21.4 +/- 2.1 years (body height 173.4 +/- 3.7, body mass 74.9 +/- 8.6 kg, body fat 12.1 +/- 1.9, training experience 5.7 +/- 1.3 years) volunteered to participate in this study. They performed a maximal graded aerobic test on a motor-driven treadmill to determine maximum oxygen uptake (VO2max), oxygen uptake (VO2AT) and heart rate (HRAT) at the anaerobic threshold, and maximal heart rate (HRmax). Additionally, VO2 and peak HR (HRpeak) were recorded following each boxing round. Results showed no significant differences between VO2max values derived from the treadmill running test and VO2 outcomes of the simulated boxing contest (p > 0.05, d = 0.02 to 0.39). However, HRmax and HRpeak recorded from the treadmill running test and the simulated amateur boxing contest, respectively, displayed significant differences regardless of the boxing round (p < 0.01, d = 1.60 to 3.00). In terms of VO2 outcomes during the simulated contest, no significant between-round differences were observed (p = 0.19, d = 0.17 to 0.73). Irrespective of the boxing round, the recorded VO2 was >90\% of the VO2max. Likewise, HRpeak observed across the three boxing rounds were >= 90\% of the HRmax. In summary, the simulated 3 x 3-min amateur boxing contest is highly demanding from a physiological standpoint. Thus, coaches are advised to systematically monitor internal training load for instance through rating of perceived exertion to optimize training-related adaptations and to prevent boxers from overreaching and/or overtraining.},
language = {en}
}
@article{AlbertOwolabiGebeletal.2020,
author = {Albert, Justin Amadeus and Owolabi, Victor and Gebel, Arnd and Brahms, Clemens Markus and Granacher, Urs and Arnrich, Bert},
title = {Evaluation of the Pose Tracking Performance of the Azure Kinect and Kinect v2 for Gait Analysis in Comparison with a Gold Standard},
series = {Sensors},
volume = {20},
journal = {Sensors},
number = {18},
publisher = {MDPI},
address = {Basel},
issn = {1424-8220},
doi = {10.3390/s20185104},
pages = {22},
year = {2020},
abstract = {Gait analysis is an important tool for the early detection of neurological diseases and for the assessment of risk of falling in elderly people. The availability of low-cost camera hardware on the market today and recent advances in Machine Learning enable a wide range of clinical and health-related applications, such as patient monitoring or exercise recognition at home. In this study, we evaluated the motion tracking performance of the latest generation of the Microsoft Kinect camera, Azure Kinect, compared to its predecessor Kinect v2 in terms of treadmill walking using a gold standard Vicon multi-camera motion capturing system and the 39 marker Plug-in Gait model. Five young and healthy subjects walked on a treadmill at three different velocities while data were recorded simultaneously with all three camera systems. An easy-to-administer camera calibration method developed here was used to spatially align the 3D skeleton data from both Kinect cameras and the Vicon system. With this calibration, the spatial agreement of joint positions between the two Kinect cameras and the reference system was evaluated. In addition, we compared the accuracy of certain spatio-temporal gait parameters, i.e., step length, step time, step width, and stride time calculated from the Kinect data, with the gold standard system. Our results showed that the improved hardware and the motion tracking algorithm of the Azure Kinect camera led to a significantly higher accuracy of the spatial gait parameters than the predecessor Kinect v2, while no significant differences were found between the temporal parameters. Furthermore, we explain in detail how this experimental setup could be used to continuously monitor the progress during gait rehabilitation in older people.},
language = {en}
}
@article{BenOthmanChaouachiChaouachietal.2019,
author = {Ben Othman, Aymen and Chaouachi, Anis and Chaouachi, Mehdi and Makhlouf, Issam and Farthing, Jonathan P. and Granacher, Urs and Behm, David George},
title = {Dominant and nondominant leg press training induce similar contralateral and ipsilateral limb training adaptations with children},
series = {Applied Physiology, Nutrition, and Metabolism},
volume = {44},
journal = {Applied Physiology, Nutrition, and Metabolism},
number = {9},
publisher = {NRC Research Press},
address = {Ottawa},
issn = {1715-5312},
doi = {10.1139/apnm-2018-0766},
pages = {973 -- 984},
year = {2019},
abstract = {Cross-education has been extensively investigated with adults. Adult studies report asymmetrical cross-education adaptations predominately after dominant limb training. The objective of the study was to examine unilateral leg press (LP) training of the dominant or nondominant leg on contralateral and ipsilateral strength and balance measures. Forty-two youth (10-13 years) were placed (random allocation) into a dominant (n = 15) or nondominant (n = 14) leg press training group or nontraining control (n = 13). Experimental groups trained 3 times per week for 8 weeks and were tested pre-/post-training for ipsilateral and contralateral 1-repetition maximum (RM) horizontal LP, maximum voluntary isometric contraction (MVIC) of knee extensors (KE) and flexors (KF), countermovement jump (CMJ), triple hop test (THT), MVIC strength of elbow flexors (EF) and handgrip, as well as the stork and Y balance tests. Both dominant and nondominant LP training significantly (p < 0.05) increased both ipsilateral and contralateral lower body strength (LP 1RM (dominant: 59.6\%-81.8\%; nondominant: 59.5\%-96.3\%), KE MVIC (dominant: 12.4\%-18.3\%; nondominant: 8.6\%-18.6\%), KF MVIC (dominant: 7.9\%-22.3\%; nondominant: nonsignificant-3.8\%), and power (CMJ: dominant: 11.1\%-18.1\%; nondominant: 7.7\%-16.6\%)). The exception was that nondominant LP training demonstrated a nonsignificant change with the contralateral KF MVIC. Other significant improvements were with nondominant LP training on ipsilateral EF 1RM (6.2\%) and THT (9.6\%). There were no significant changes with EF and handgrip MVIC. The contralateral leg stork balance test was impaired following dominant LP training. KF MVIC exhibited the only significant relative post-training to pretraining (post-test/pre-test) ratio differences between dominant versus nondominant LP cross-education training effects. In conclusion, children exhibit symmetrical cross-education or global training adaptations with unilateral training of dominant or nondominant upper leg.},
language = {en}
}