TY - GEN A1 - Granacher, Urs A1 - Schellbach, Jörg A1 - Klein, Katja A1 - Prieske, Olaf A1 - Baeyens, Jean-Pierre A1 - Mühlbauer, Thomas T1 - Effects of core strength training using stable versus unstable surfaces on physical fitness in adolescents BT - a randomized controlled trial N2 - Background It has been demonstrated that core strength training is an effective means to enhance trunk muscle strength (TMS) and proxies of physical fitness in youth. Of note, cross-sectional studies revealed that the inclusion of unstable elements in core strengthening exercises produced increases in trunk muscle activity and thus provide potential extra training stimuli for performance enhancement. Thus, utilizing unstable surfaces during core strength training may even produce larger performance gains. However, the effects of core strength training using unstable surfaces are unresolved in youth. This randomized controlled study specifically investigated the effects of core strength training performed on stable surfaces (CSTS) compared to unstable surfaces (CSTU) on physical fitness in school-aged children. Methods Twenty-seven (14 girls, 13 boys) healthy subjects (mean age: 14 ± 1 years, age range: 13–15 years) were randomly assigned to a CSTS (n = 13) or a CSTU (n = 14) group. Both training programs lasted 6 weeks (2 sessions/week) and included frontal, dorsal, and lateral core exercises. During CSTU, these exercises were conducted on unstable surfaces (e.g., TOGU© DYNAIR CUSSIONS, THERA-BAND© STABILITY TRAINER). Results Significant main effects of Time (pre vs. post) were observed for the TMS tests (8-22%, f = 0.47-0.76), the jumping sideways test (4-5%, f = 1.07), and the Y balance test (2-3%, f = 0.46-0.49). Trends towards significance were found for the standing long jump test (1-3%, f = 0.39) and the stand-and-reach test (0-2%, f = 0.39). We could not detect any significant main effects of Group. Significant Time x Group interactions were detected for the stand-and-reach test in favour of the CSTU group (2%, f = 0.54). Conclusions Core strength training resulted in significant increases in proxies of physical fitness in adolescents. However, CSTU as compared to CSTS had only limited additional effects (i.e., stand-and-reach test). Consequently, if the goal of training is to enhance physical fitness, then CSTU has limited advantages over CSTS. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 297 KW - Resistance training KW - Trunk muscle strength KW - Physical fitness Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-93490 ER - TY - JOUR A1 - Jafarnezhadgero, Amir Ali A1 - Amirzadeh, Nasrin A1 - Fatollahi, Amir A1 - Siahkouhian, Marefat A1 - de Souza Castelo Oliveira, Anderson A1 - Granacher, Urs T1 - Effects of running on sand vs. stable ground on kinetics and muscle activities in individuals with over-pronated feet JF - Frontiers in physiology / Frontiers Research Foundation N2 - 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. KW - flat feet KW - loading rate KW - lower limb mechanics KW - unstable walkway KW - muscle Y1 - 2022 U6 - https://doi.org/10.3389/fphys.2021.822024 SN - 1664-042X VL - 12 SP - 1 EP - 10 PB - Frontiers Research Foundation CY - Lausanne, Schweiz ER - TY - JOUR A1 - Granacher, Urs A1 - Kiss, Rainer A1 - Lüder, Benjamin T1 - Single- and Dual-Task Balance Training Are Equally Effective in Youth JF - Frontiers in Psychology N2 - Due to maturation of the postural control system and secular declines in motor performance, adolescents experience deficits in postural control during standing and walking while concurrently performing cognitive interference tasks. Thus, adequately designed balance training programs may help to counteract these deficits. While the general effectiveness of youth balance training is well-documented, there is hardly any information available on the specific effects of single-task (ST) versus dual-task (DT) balance training. Therefore, the objectives of this study were (i) to examine static/dynamic balance performance under ST and DT conditions in adolescents and (ii) to study the effects of ST versus DT balance training on static/dynamic balance under ST and DT conditions in adolescents. Twenty-eight healthy girls and boys aged 12–13 years were randomly assigned to either 8 weeks of ST or DT balance training. Before and after training, postural sway and spatio-temporal gait parameters were registered under ST (standing/walking only) and DT conditions (standing/walking while concurrently performing an arithmetic task). At baseline, significantly slower gait speed (p < 0.001, d = 5.1), shorter stride length (p < 0.001, d = 4.8), and longer stride time (p < 0.001, d = 3.8) were found for DT compared to ST walking but not standing. Training resulted in significant pre–post decreases in DT costs for gait velocity (p < 0.001, d = 3.1), stride length (-45%, p < 0.001, d = 2.4), and stride time (-44%, p < 0.01, d = 1.9). Training did not induce any significant changes (p > 0.05, d = 0–0.1) in DT costs for all parameters of secondary task performance during standing and walking. Training produced significant pre–post increases (p = 0.001; d = 1.47) in secondary task performance while sitting. The observed increase was significantly greater for the ST training group (p = 0.04; d = 0.81). For standing, no significant changes were found over time irrespective of the experimental group. We conclude that adolescents showed impaired DT compared to ST walking but not standing. ST and DT balance training resulted in significant and similar changes in DT costs during walking. Thus, there appears to be no preference for either ST or DT balance training in adolescents. KW - postural control KW - cognitive performance KW - attentional demand KW - dual-task costs KW - cognitive interference Y1 - 2018 U6 - https://doi.org/10.3389/fpsyg.2018.00912 SN - 1664-1078 VL - 9 SP - 1 EP - 12 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Negra, Yassine A1 - Chaabene, Helmi A1 - Fernandez-Fernandez, Jaime A1 - Sammoud, Senda A1 - Bouguezzi, Raja A1 - Prieske, Olaf A1 - Granacher, Urs T1 - Short-term plyometric Jump training improves repeated-sprint ability in prepuberal male soccer players JF - Journal of strength and conditioning research : the research journal of the NSCA N2 - 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. KW - youth KW - stretch-shortening cycle KW - athletic performance KW - soccer Y1 - 2020 U6 - https://doi.org/10.1519/JSC.0000000000002703 SN - 1064-8011 SN - 1533-4287 VL - 34 IS - 11 SP - 3241 EP - 3249 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Lesinski, Melanie A1 - Prieske, Olaf A1 - Granacher, Urs T1 - Effects and dose-response relationships of resistance training on physical performance in youth athletes: a systematic review and meta-analysis JF - British journal of sports medicine : the journal of sport and exercise medicine N2 - Objectives To quantify age, sex, sport and training type-specific effects of resistance training on physical performance, and to characterise dose-response relationships of resistance training parameters that could maximise gains in physical performance in youth athletes. Design Systematic review and meta-analysis of intervention studies. Data sources Studies were identified by systematic literature search in the databases PubMed and Web of Science (1985-2015). Weighted mean standardised mean differences (SMDwm) were calculated using random-effects models. Eligibility criteria for selecting studies Only studies with an active control group were included if these investigated the effects of resistance training in youth athletes (6-18 years) and tested at least one physical performance measure. Results 43 studies met the inclusion criteria. Our analyses revealed moderate effects of resistance training on muscle strength and vertical jump performance (SMDwm 0.8-1.09), and small effects on linear sprint, agility and sport-specific performance (SMDwm 0.58-0.75). Effects were moderated by sex and resistance training type. Independently computed dose-response relationships for resistance training parameters revealed that a training period of >23 weeks, 5 sets/exercise, 6-8 repetitions/set, a training intensity of 80-89% of 1 repetition maximum (RM), and 3-4 min rest between sets were most effective to improve muscle strength (SMDwm 2.09-3.40). Summary/conclusions Resistance training is an effective method to enhance muscle strength and jump performance in youth athletes, moderated by sex and resistance training type. Dose-response relationships for key training parameters indicate that youth coaches should primarily implement resistance training programmes with fewer repetitions and higher intensities to improve physical performance measures of youth athletes. Y1 - 2016 U6 - https://doi.org/10.1136/bjsports-2015-095497 SN - 0306-3674 SN - 1473-0480 VL - 50 SP - 781 EP - 795 PB - BMJ Publishing Group CY - London ER - TY - JOUR A1 - Lacroix, Andre A1 - Kressig, Reto W. A1 - Mühlbauer, Thomas A1 - Gschwind, Yves J. A1 - Pfenninger, Barbara A1 - Bruegger, Othmar A1 - Granacher, Urs T1 - Effects of a Supervised versus an Uniupervised Combined Balance and Strength Training Program on Balance and Muscle Power in Healthy Older Adults: A Randomized Controlled Trial JF - Gerontology N2 - Background: Losses in lower extremity muscle strength/power, muscle mass and deficits in static and particularly dynamic balance due to aging are associated with impaired functional performance and an increased fall risk. It has been shown that the combination of balance and strength training (BST) mitigates these age-related deficits. However, it is unresolved whether supervised versus unsupervised BST is equally effective in improving muscle power and balance in older adults. Objective:This study examined the impact of a 12-week BST program followed by 12 weeks of detraining on measures of balance and muscle power in healthy older adults enrolled in supervised (SUP) or unsupervised (UNSUP) training. Methods: Sixty-six older adults (men: 25, women: 41; age 73 4 years) were randomly assigned to a SUP group (2/week supervised training, 1/week unsupervised training; n = 22), an UNSUP group (3/week unsupervised training; n = 22) or a passive control group (CON; n = 22). Static (i.e., Romberg Test) and dynamic (i.e., 10-meter walk test) steady-state, proactive (i.e., Timed Up and Go Test, Functional Reach Test), and reactive balance (e.g., Push and Release Test), as well as lower extremity muscle power (i.e., Chair Stand Test; Stair Ascent and Descent Test) were tested before and after the active training phase as well as after detraining. Results: Adherence rates to training were 92% for SUP and 97% for UNSUP. BST resulted in significant group x time interactions. Post hoc analyses showed, among others, significant training-related improvements for the Romberg Test, stride velocity, Timed Up and Go Test, and Chair Stand Test in favor of the SUP group. Following detraining, significantly enhanced performances (compared to baseline) were still present in 13 variables for the SUP group and in 10 variables for the UNSUP group. Conclusion: Twelve weeks of BST proved to be safe (no training-related injuries) and feasible (high attendance rates of >90%). Deficits of balance and lower extremity muscle power can be mitigated by BST in healthy older adults. Additionally, supervised as compared to unsupervised BST was more effective. Thus, it is recommended to counteract intrinsic fall risk factors by applying supervised BST programs for older adults. (C) 2015 The Author(s) Published by S. Karger AG, Basel KW - Sensorimotor training KW - Resistance training KW - Gym-based/home-based training KW - Detraining KW - Seniors Y1 - 2016 U6 - https://doi.org/10.1159/000442087 SN - 0304-324X SN - 1423-0003 VL - 62 SP - 275 EP - 288 PB - Karger CY - Basel ER - TY - JOUR A1 - Peitz, Matti A1 - Behringer, Michael A1 - Granacher, Urs T1 - A systematic review on the effects of resistance and plyometric training on physical fitness in youth BT - What do comparative studies tell us? JF - PlOS ONE N2 - Introduction To date, several meta-analyses clearly demonstrated that resistance and plyometric training are effective to improve physical fitness in children and adolescents. However, a methodological limitation of meta-analyses is that they synthesize results from different studies and hence ignore important differences across studies (i.e., mixing apples and oranges). Therefore, we aimed at examining comparative intervention studies that assessed the effects of age, sex, maturation, and resistance or plyometric training descriptors (e.g., training intensity, volume etc.) on measures of physical fitness while holding other variables constant. Methods To identify relevant studies, we systematically searched multiple electronic databases (e.g., PubMed) from inception to March 2018. We included resistance and plyometric training studies in healthy young athletes and non-athletes aged 6 to 18 years that investigated the effects of moderator variables (e.g., age, maturity, sex, etc.) on components of physical fitness (i.e., muscle strength and power). Results Our systematic literature search revealed a total of 75 eligible resistance and plyometric training studies, including 5,138 participants. Mean duration of resistance and plyometric training programs amounted to 8.9 ± 3.6 weeks and 7.1±1.4 weeks, respectively. Our findings showed that maturation affects plyometric and resistance training outcomes differently, with the former eliciting greater adaptations pre-peak height velocity (PHV) and the latter around- and post-PHV. Sex has no major impact on resistance training related outcomes (e.g., maximal strength, 10 repetition maximum). In terms of plyometric training, around-PHV boys appear to respond with larger performance improvements (e.g., jump height, jump distance) compared with girls. Different types of resistance training (e.g., body weight, free weights) are effective in improving measures of muscle strength (e.g., maximum voluntary contraction) in untrained children and adolescents. Effects of plyometric training in untrained youth primarily follow the principle of training specificity. Despite the fact that only 6 out of 75 comparative studies investigated resistance or plyometric training in trained individuals, positive effects were reported in all 6 studies (e.g., maximum strength and vertical jump height, respectively). Conclusions The present review article identified research gaps (e.g., training descriptors, modern alternative training modalities) that should be addressed in future comparative studies. KW - young soccer players KW - randomized controlled-trial KW - school baseball players KW - whole-body vibratoin KW - rugby league players KW - of-direction speed KW - endurance performance KW - muscular strength KW - motor-performance Y1 - 2018 U6 - https://doi.org/10.1371/journal.pone.0205525 SN - 1932-6203 VL - 13 IS - 10 PB - Public Library of Science CY - San Francisco ER - TY - JOUR A1 - Fernandez-Fernandez, Jaime A1 - Granacher, Urs A1 - Sanz-Rivas, David A1 - Sarabia Marin, Jose Manuel A1 - Luis Hernandez-Davo, Jose A1 - Moya, Manuel T1 - Sequencing Effects of Neuromuscular Training on Physical Fitness in Youth Elite Tennis Players JF - Journal of strength and conditioning research : the research journal of the NSCA N2 - 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. KW - athletic performance KW - intermittent sport KW - plyometrics KW - speed KW - change of direction Y1 - 2018 U6 - https://doi.org/10.1519/JSC.0000000000002319 SN - 1064-8011 SN - 1533-4287 VL - 32 IS - 3 SP - 849 EP - 856 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Singh, Gaurav A1 - Kushwah, Gaurav Singh A1 - Singh, Tanvi A1 - Thapa, Rohit Kumar A1 - Granacher, Urs A1 - Ramirez-Campillo, Rodrigo T1 - Effects of sand-based plyometric-jump training in combination with endurance running on outdoor or treadmill surface on physical fitness in young adult males JF - Journal of sports science & medicine N2 - 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). KW - Muscle strength KW - musculoskeletal and neural physiological phenomena KW - movement KW - resistance training KW - high-intensity interval training KW - exercise Y1 - 2022 U6 - https://doi.org/10.52082/jssm.2022.277 SN - 1303-2968 VL - 21 IS - 2 SP - 277 EP - 286 PB - Department of Sports Medicine, Medical Faculty of Uludag University CY - Bursa ER - TY - JOUR A1 - Jafarnezhadgero, Amir Ali A1 - Piran Hamlabadi, Milad A1 - Sajedi, Heidar A1 - Granacher, Urs T1 - Recreational runners who recovered from COVID-19 show different running kinetics and muscle activities compared with healthy controls JF - Gait & posture : official journal of Gait and Clinical Movement Analysis Society, European Society of Movement Analysis in Adults and Children, Società Italiana di Analisi del Movimento in Clinica, International Society for Posture and Gait Research N2 - 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. KW - Quarantine KW - Ground reaction force KW - Electromyography Y1 - 2022 U6 - https://doi.org/10.1016/j.gaitpost.2021.11.002 SN - 0966-6362 SN - 1879-2219 VL - 91 SP - 260 EP - 265 PB - Elsevier CY - Amsterdam [u.a.] ER - TY - JOUR A1 - Wick, Kristin A1 - Kriemler, Susi A1 - Granacher, Urs T1 - Associations between measures of physical fitness and cognitive performance in preschool children JF - BMC sports science, medicine & rehabilitation N2 - 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. KW - Motor skills KW - Cognitive skills KW - Attention KW - Kindergarten Y1 - 2022 U6 - https://doi.org/10.1186/s13102-022-00470-w SN - 2052-1847 VL - 14 IS - 1 PB - BMC CY - London ER - TY - JOUR A1 - Zghal, Firas A1 - Colson, Serge S. A1 - Blain, Grégory A1 - Behm, David George A1 - Granacher, Urs A1 - Chaouachi, Anis T1 - Combined Resistance and Plyometric Training Is More Effective Than Plyometric Training Alone for Improving Physical Fitness of Pubertal Soccer Players JF - frontiers in Physiology N2 - The purpose of this study was to compare the effects of combined resistance and plyometric/sprint training with plyometric/sprint training or typical soccer training alone on muscle strength and power, speed, change-of-direction ability in young soccer players. Thirty-one young (14.5 ± 0.52 years; tanner stage 3–4) soccer players were randomly assigned to either a combined- (COMB, n = 14), plyometric-training (PLYO, n = 9) or an active control group (CONT, n = 8). Two training sessions were added to the regular soccer training consisting of one session of light-load high-velocity resistance exercises combined with one session of plyometric/sprint training (COMB), two sessions of plyometric/sprint training (PLYO) or two soccer training sessions (CONT). Training volume was similar between the experimental groups. Before and after 7-weeks of training, peak torque, as well as absolute and relative (normalized to torque; RTDr) rate of torque development (RTD) during maximal voluntary isometric contraction of the knee extensors (KE) were monitored at time intervals from the onset of contraction to 200 ms. Jump height, sprinting speed at 5, 10, 20-m and change-of-direction ability performances were also assessed. There were no significant between–group baseline differences. Both COMB and PLYO significantly increased their jump height (Δ14.3%; ES = 0.94; Δ12.1%; ES = 0.54, respectively) and RTD at mid to late phases but with greater within effect sizes in COMB in comparison with PLYO. However, significant increases in peak torque (Δ16.9%; p < 0.001; ES = 0.58), RTD (Δ44.3%; ES = 0.71), RTDr (Δ27.3%; ES = 0.62) and sprint performance at 5-m (Δ-4.7%; p < 0.001; ES = 0.73) were found in COMB without any significant pre-to-post change in PLYO and CONT groups. Our results suggest that COMB is more effective than PLYO or CONT for enhancing strength, sprint and jump performances. KW - strength KW - power KW - rate of torque development KW - jumping KW - running Y1 - 2019 U6 - https://doi.org/10.3389/fphys.2019.01026 SN - 1664-042X VL - 10 IS - August 2019 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Golle, Kathleen A1 - Granacher, Urs A1 - Hoffmann, Martin A1 - Wick, Ditmar A1 - Mühlbauer, Thomas T1 - Effect of living area and sports club participation on physical fitness in children: a 4 year longitudinal study JF - BMC public health N2 - Background: Cross-sectional studies detected associations between physical fitness, living area, and sports participation in children. Yet, their scientific value is limited because the identification of cause-and-effect relationships is not possible. In a longitudinal approach, we examined the effects of living area and sports club participation on physical fitness development in primary school children from classes 3 to 6. Methods: One-hundred and seventy-two children (age: 9-12 years; sex: 69 girls, 103 boys) were tested for their physical fitness (i.e., endurance [9-min run], speed [50-m sprint], lower- [triple hop] and upper-extremity muscle strength [1-kg ball push], flexibility [stand-and-reach], and coordination [star coordination run]). Living area (i.e., urban or rural) and sports club participation were assessed using parent questionnaire. Results: Over the 4 year study period, urban compared to rural children showed significantly better performance development for upper- (p = 0.009, ES = 0.16) and lower-extremity strength (p < 0.001, ES = 0.22). Further, significantly better performance development were found for endurance (p = 0.08, ES = 0.19) and lower-extremity strength (p = 0.024, ES = 0.23) for children continuously participating in sports clubs compared to their non-participating peers. Conclusions: Our findings suggest that sport club programs with appealing arrangements appear to represent a good means to promote physical fitness in children living in rural areas. KW - Motor performance KW - Youth KW - Primary school KW - Maturation Y1 - 2014 U6 - https://doi.org/10.1186/1471-2458-14-499 SN - 1471-2458 VL - 14 PB - BioMed Central CY - London ER - TY - JOUR A1 - Prieske, Olaf A1 - Wick, Ditmar A1 - Granacher, Urs T1 - Intrasession and intersession reliability in maximal and explosive isometric torque production of the elbow flexors JF - Journal of strength and conditioning research : the research journal of the NSCA N2 - The purpose of this study was to assess intrasession and intersession reliability of maximal and explosive isometric torque production of the elbow flexors and its respective neuromuscular activation pattern. Subjects (13 men, age: 24.8 +/- 3.1 years, height: 1.9 +/- 0.1 m, body mass: 83.7 +/- 12.7 kg; and 6 women, age: 26.5 +/- 1.4 years, height: 1.7 +/- 0.1 m, body mass: 62.7 +/- 7.0 kg) were tested and retested 2-7 days later performing unilateral maximal isometric elbow flexions. Absolute (coefficient of variation[CV], test-retest variability[TRV], Bland-Altman plots with 95% limits of agreement) and relative reliability statistics (intraclass correlation coefficient) were calculated for various mechanical (i.e., maximal isometric torque, rate of torque development, impulse) and electromyographical measures (i.e., mean average voltage) at different time intervals relative to onset of torque (i. e., 30, 50, 100, 200, 300, 400, 100-200 ms). Intraclass correlation coefficient values were >= 0.61 for all mechanical and electromyographical measures and time intervals indicating good to excellent intrasession and intersession reliability. BlandAltman plots confirmed these findings by showing that only 0-2 (<= 3.3%) data points were beyond the limits of agreement. Regarding torque and electromyographic measures, CV (11.9-32.3%) and TRV (18.4-53.8%) values were high during the early intervals of torque development (<= 100 ms) indicating high variability. During the later intervals (>100 ms), lower CV (i. e., 5.0-29.9%) and TRV values (i.e., 5.4-34.6%) were observed indicating lower variability. The present study revealed that neuromuscular performance during explosive torque production of the elbow flexors is reproducible in time intervals >100 ms after onset of isometric actions, whereas during earlier time intervals variability is high. KW - maximal isometric contraction KW - explosive force production KW - electromyography KW - test-retest reliability Y1 - 2014 SN - 1064-8011 SN - 1533-4287 VL - 28 IS - 6 SP - 1771 EP - 1777 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Meyer, Ursina A1 - Ernst, Dominique A1 - Schott, Silvia A1 - Riera, Claudia A1 - Hattendorf, Jan A1 - Romkes, Jacqueline A1 - Granacher, Urs A1 - Göpfert, Beat A1 - Kriemler, Susi T1 - Validation of two accelerometers to determine mechanical loading of physical activities in children JF - Journal of sports sciences N2 - The purpose of this study was to assess the validity of accelerometers using force plates (i.e., ground reaction force (GRF)) during the performance of different tasks of daily physical activity in children. Thirteen children (10.1 (range 5.4-15.7)years, 3 girls) wore two accelerometers (ActiGraph GT3X+ (ACT), GENEA (GEN)) at the hip that provide raw acceleration signals at 100Hz. Participants completed different tasks (walking, jogging, running, landings from boxes of different height, rope skipping, dancing) on a force plate. GRF was collected for one step per trial (10 trials) for ambulatory movements and for all landings (10 trials), rope skips and dance procedures. Accelerometer outputs as peak loading (g) per activity were averaged. ANOVA, correlation analyses and Bland-Altman plots were computed to determine validity of accelerometers using GRF. There was a main effect of task with increasing acceleration values in tasks with increasing locomotion speed and landing height (P<0.001). Data from ACT and GEN correlated with GRF (r=0.90 and 0.89, respectively) and between each other (r=0.98), but both accelerometers consistently overestimated GRF. The new generation of accelerometer models that allow raw signal detection are reasonably accurate to measure impact loading of bone in children, although they systematically overestimate GRF. KW - bone KW - impact loading KW - children KW - physical activity KW - ground reaction force Y1 - 2015 U6 - https://doi.org/10.1080/02640414.2015.1004638 SN - 0264-0414 SN - 1466-447X VL - 33 IS - 16 SP - 1702 EP - 1709 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - Mühlbauer, Thomas A1 - Mettler, Claude A1 - Roth, Ralf A1 - Granacher, Urs T1 - One-leg standing performance and muscle activity: Are there limb differences? JF - Journal of applied biomechanics N2 - The purpose of this study was to compare static balance performance and muscle activity during one-leg standing on the dominant and nondominant leg under various sensory conditions with increased levels of task difficulty. Thirty healthy young adults (age: 23 +/- 2 years) performed one-leg standing tests for 30 s under three sensory conditions (ie, eyes open/firm ground; eyes open/foam ground [elastic pad on top of the balance plate]; eyes closed/firm ground). Center of pressure displacements and activity of four lower leg muscles (ie, m. tibialis anterior [TA], m. soleus [SOL], m. gastrocnemius medialis [GAS], m. peroneus longus [PER]) were analyzed. An increase in sensory task difficulty resulted in deteriorated balance performance (P < .001, effect size [ES] = .57-2.54) and increased muscle activity (P < .001, ES = .50-1.11) for all but two muscles (ie, GAS, PER). However, regardless of the sensory condition, one-leg standing on the dominant as compared with the nondominant limb did not produce statistically significant differences in various balance (P > .05, ES = .06-.22) and electromyographic (P > .05, ES = .03-.13) measures. This indicates that the dominant and the nondominant leg can be used interchangeably during static one-leg balance testing in healthy young adults. KW - postural control KW - electromyography KW - sensory input KW - task difficulty Y1 - 2014 U6 - https://doi.org/10.1123/jab.2013-0230 SN - 1065-8483 SN - 1543-2688 VL - 30 IS - 3 SP - 407 EP - 414 PB - Human Kinetics Publ. CY - Champaign ER - TY - JOUR A1 - Golle, Kathleen A1 - Mühlbauer, Thomas A1 - Wick, Ditmar A1 - Granacher, Urs T1 - Physical Fitness Percentiles of German Children Aged 9-12 Years: Findings from a Longitudinal Study JF - PLoS one N2 - Background Generating percentile values is helpful for the identification of children with specific fitness characteristics (i. e., low or high fitness level) to set appropriate fitness goals (i. e., fitness/ health promotion and/or long-term youth athlete development). Thus, the aim of this longitudinal study was to assess physical fitness development in healthy children aged 9-12 years and to compute sex-and age-specific percentile values. Methods Two-hundred and forty children (88 girls, 152 boys) participated in this study and were tested for their physical fitness. Physical fitness was assessed using the 50-m sprint test (i. e., speed), the 1-kg ball push test, the triple hop test (i. e., upper-and lower-extremity muscular power), the stand-and-reach test (i. e., flexibility), the star run test (i. e., agility), and the 9-min run test (i. e., endurance). Age-and sex-specific percentile values (i. e., P-10 to P-90) were generated using the Lambda, Mu, and Sigma method. Adjusted (for change in body weight, height, and baseline performance) age-and sex-differences as well as the interactions thereof were expressed by calculating effect sizes (Cohen's d). Results Significant main effects of Age were detected for all physical fitness tests (d = 0.40-1.34), whereas significant main effects of Sex were found for upper-extremity muscular power (d = 0.55), flexibility (d = 0.81), agility (d = 0.44), and endurance (d = 0.32) only. Further, significant Sex by Age interactions were observed for upper-extremity muscular power (d = 0.36), flexibility (d = 0.61), and agility (d = 0.27) in favor of girls. Both, linear and curvilinear shaped curves were found for percentile values across the fitness tests. Accelerated (curvilinear) improvements were observed for upper-extremity muscular power (boys: 10-11 yrs; girls: 9-11 yrs), agility (boys: 9-10 yrs; girls: 9-11 yrs), and endurance (boys: 9-10 yrs; girls: 9-10 yrs). Tabulated percentiles for the 9-min run test indicated that running distances between 1,407-1,507 m, 1,479-1,597 m, 1,423-1,654 m, and 1,433-1,666 m in 9-to 12-year-old boys and 1,262-1,362 m, 1,329-1,434 m, 1,392-1,501 m, and 1,415-1,526 m in 9-to 12-year-old girls correspond to a "medium" fitness level (i. e., P-40 to P-60) in this population. Conclusions The observed differences in physical fitness development between boys and girls illustrate that age- and sex-specific maturational processes might have an impact on the fitness status of healthy children. Our statistical analyses revealed linear (e. g., lower-extremity muscular power) and curvilinear (e. g., agility) models of fitness improvement with age which is indicative of timed and capacity-specific fitness development pattern during childhood. Lastly, the provided age-and sex-specific percentile values can be used by coaches for talent identification and by teachers for rating/ grading of children's motor performance. Y1 - 2015 U6 - https://doi.org/10.1371/journal.pone.0142393 SN - 1932-6203 VL - 10 IS - 11 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Beurskens, Rainer A1 - Gollhofer, Albert A1 - Mühlbauer, Thomas A1 - Cardinale, Marco A1 - Granacher, Urs T1 - Effects of Heavy-Resistance Strength and Balance Training on Unilateral and Bilateral Leg Strength Performance in Old Adults JF - PLoS one N2 - The term "bilateral deficit" (BLD) has been used to describe a reduction in performance during bilateral contractions when compared to the sum of identical unilateral contractions. In old age, maximal isometric force production (MIF) decreases and BLD increases indicating the need for training interventions to mitigate this impact in seniors. In a cross-sectional approach, we examined age-related differences in MIF and BLD in young (age: 20-30 years) and old adults (age: > 65 years). In addition, a randomized-controlled trial was conducted to investigate training-specific effects of resistance vs. balance training on MIF and BLD of the leg extensors in old adults. Subjects were randomly assigned to resistance training (n = 19), balance training (n = 14), or a control group (n = 20). Bilateral heavy-resistance training for the lower extremities was performed for 13 weeks (3 x /week) at 80% of the one repetition maximum. Balance training was conducted using predominately unilateral exercises on wobble boards, soft mats, and uneven surfaces for the same duration. Pre-and post-tests included uni-and bilateral measurements of maximal isometric leg extension force. At baseline, young subjects outperformed older adults in uni-and bilateral MIF (all p < .001; d = 2.61-3.37) and in measures of BLD (p < .001; d = 2.04). We also found significant increases in uni-and bilateral MIF after resistance training (all p < .001, d = 1.8-5.7) and balance training (all p < .05, d = 1.3-3.2). In addition, BLD decreased following resistance (p < .001, d = 3.4) and balance training (p < .001, d = 2.6). It can be concluded that both training regimens resulted in increased MIF and decreased BLD of the leg extensors (HRT-group more than BAL-group), almost reaching the levels of young adults. Y1 - 2015 U6 - https://doi.org/10.1371/journal.pone.0118535 SN - 1932-6203 VL - 10 IS - 2 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Howard, Joshua A1 - Granacher, Urs A1 - Behm, David George T1 - Trunk extensor fatigue decreases jump height similarly under stable and unstable conditions with experienced jumpers JF - European journal of applied physiology N2 - The purpose of this study was to investigate the effects of back extensor fatigue on performance measures and electromyographic (EMG) activity of leg and trunk muscles during jumping on stable and unstable surfaces. Before and after a modified Biering-Sorensen fatigue protocol for the back extensors, countermovement (CMJ) and lateral jumps (LJ) were performed on a force plate under stable and unstable (balance pad on the force plate) conditions. Performance measures for LJ (contact time) and CMJ height and leg and trunk muscles EMG activity were tested in 14 male experienced jumpers during 2 time intervals for CMJ (braking phase, push-off phase) and 5 intervals for LJ (-30 to 0, 0-30, 30-60, 60-90, and 90-120 ms) in non-fatigued and fatigued conditions. A significant main effect of test (fatigue) (p = 0.007, f = 0.57) was observed for CMJ height. EMG analysis showed a significant fatigue-induced decrease in biceps femoris and gastrocnemius activity with CMJ (p = 0.008, f = 0.58 andp = 0.04, f = 0.422, respectively). LJ contact time was not affected by fatigue or surface interaction. EMG activity was significantly lower in the tibialis anterior with LJ following fatigue (p = 0.05, f = 0.405). A test x surface (p = 0.04, f = 0.438) interaction revealed that the non-fatigued unstable CMJ gastrocnemius EMG activity was lower than the non-fatigued stable condition during the onset-of-force phase. The findings revealed that fatiguing the trunk negatively impacts CMJ height and muscle activity during the performance of CMJs. However, skilled jumpers are not additionally affected by a moderately unstable surface as compared to a stable surface. KW - Countermovement jump KW - Instability KW - Balance KW - Crossover fatigue KW - Lateral jumps Y1 - 2015 U6 - https://doi.org/10.1007/s00421-014-3011-x SN - 1439-6319 SN - 1439-6327 VL - 115 IS - 2 SP - 285 EP - 294 PB - Springer CY - New York ER - TY - JOUR A1 - Prieske, Olaf A1 - Mühlbauer, Thomas A1 - Krüger, Tom A1 - Kibele, A. A1 - Behm, David George A1 - Granacher, Urs T1 - Sex-Specific effects of surface instability on drop jump and landing biomechanics JF - International journal of sports medicine N2 - This study investigated sex-specific effects of surface instability on kinetics and lower extremity kinematics during drop jumping and landing. Ground reaction forces as well as knee valgus and flexion angles were tested in 14 males (age: 23 +/- 2 years) and 14 females (age: 24 +/- 3 years) when jumping and landing on stable and unstable surfaces. Jump height was found to be significantly lower (9 %, p < 0.001) when drop jumps were performed on unstable vs. stable surface. Significantly higher peak ground reaction forces were observed when jumping was performed on unstable vs. stable surfaces (5 %, p = 0.022). Regarding frontal plane kinematics during jumping and landing, knee valgus angles were higher on unstable compared to stable surfaces (1932 %, p < 0.05). Additionally, at the onset of ground contact during landings, females showed higher knee valgus angles than males (222 %, p = 0.027). Sagittal plane kinematics indicated significantly smaller knee flexion angles (6-35 %, p < 0.05) when jumping and landing on unstable vs. stable surfaces. During drop jumps and landings, women showed smaller knee flexion angles at ground contact compared to men (27-33 %, p < 0.05). These findings imply that knee motion strategies were modified by surface instability and sex during drop jumps and landings. KW - stretch-shortening cycle KW - ground reaction force KW - knee joint angle KW - injury risk Y1 - 2015 U6 - https://doi.org/10.1055/s-0034-1384549 SN - 0172-4622 SN - 1439-3964 VL - 36 IS - 1 SP - 75 EP - 81 PB - Thieme CY - Stuttgart ER - TY - JOUR A1 - Sammoud, Senda A1 - Negra, Yassine A1 - Bouguezzi, Raja A1 - Hachana, Younes A1 - Granacher, Urs A1 - Chaabene, Helmi T1 - The effects of plyometric jump training on jump and sport-specific performances in prepubertal female swimmers JF - Journal of exercise science and fitness : JESF : official journal of The Society of Chinese Scholars on Exercise Physiology and Fitness and Hong Kong Association of Sports Medicine & Sports Science N2 - Background/objective Dry land-training (e.g., plyometric jump training) can be a useful mean to improve swimming performance. This study examined the effects of an 8-week plyometric jump training (PJT) program on jump and sport-specific performances in prepubertal female swimmers. Methods Twenty-two girls were randomly assigned to either a plyometric jump training group (PJTG; n = 12, age: 10.01 ± 0.57 years, maturity-offset = -1.50 ± 0.50, body mass = 36.39 ± 6.32 kg, body height = 146.90 ± 7.62 cm, body mass index = 16.50 ± 1.73 kg/m2) or an active control (CG; n = 10, age: 10.50 ± 0.28 years, maturity-offset = -1.34 ± 0.51, body mass = 38.41 ± 9.42 kg, body height = 143.60 ± 5.05 cm, body mass index = 18.48 ± 3.77 kg/m2). Pre- and post-training, tests were conducted for the assessment of muscle power (e.g., countermovement-jump [CMJ], standing-long-jump [SLJ]). Sport-specific-performances were tested using the timed 25 and 50-m front crawl with a diving-start, timed 25-m front crawl without push-off from the wall (25-m WP), and a timed 25-m kick without push-off from the wall (25-m KWP). Results Findings showed a significant main effect of time for the CMJ (d = 0.78), the SLJ (d = 0.91), 25-m front crawl test (d = 2.5), and the 25-m-KWP (d = 1.38) test. Significant group × time interactions were found for CMJ, SLJ, 25-m front crawl, 50-m front crawl, 25-m KWP, and 25-m WP test (d = 0.29–1.63) in favor of PJTG (d = 1.34–3.50). No significant pre-post changes were found for CG (p > 0.05). Conclusion In sum, PJT is effective in improving muscle power and sport-specific performances in prepubertal swimmers. Therefore, PJT should be included from an early start into the regular training program of swimmers. KW - Stretch-shortening cycle KW - Young swimmers KW - Swimming performance Y1 - 2020 U6 - https://doi.org/10.1016/j.jesf.2020.07.003 SN - 1728-869x VL - 19 IS - 1 SP - 25 EP - 31 PB - Elsevier CY - Singapore ER - TY - JOUR A1 - Ravé, Guillaume A1 - Granacher, Urs A1 - Boullosa, Daniel A1 - Hackney, Anthony C. A1 - Zouhal, Hassane T1 - How to Use Global Positioning Systems (GPS) Data to Monitor Training Load in the “Real World” of Elite Soccer JF - Frontiers in Physiology KW - acute chronic workload ratio KW - injury risk KW - physical performance KW - monitoring KW - external training load Y1 - 2020 U6 - https://doi.org/10.3389/fphys.2020.00944 SN - 1664-042X VL - 11 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Hammami, Raouf A1 - Chaabene, Helmi A1 - Kharrat, Fatma A1 - Werfelli, Hanen A1 - Duncan, Michael A1 - Rebai, Haithem A1 - Granacher, Urs T1 - Acute effects of different balance exercise types on selected measures of physical fitness in youth female volleyball players JF - BMC Sports Science, Medicine and Rehabilitation N2 - 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. KW - Postural stability KW - Conditioning activity KW - Short‐term effect KW - Team sports KW - Youth Y1 - 2021 U6 - https://doi.org/10.1186/s13102-021-00249-5 SN - 1758-2555 VL - 13 PB - BioMed Central CY - London ER - TY - JOUR A1 - Ramirez-Campillo, Rodrigo A1 - Alvarez, Cristian A1 - Garcia-Hermoso, Antonio A1 - Ramirez-Velez, Robinson A1 - Gentil, Paulo A1 - Asadi, Abbas A1 - Chaabene, Helmi A1 - Moran, Jason A1 - Meylan, Cesar A1 - Garcia-de-Alcaraz, Antonio A1 - Sanchez-Sanchez, Javier A1 - Nakamura, Fabio Y. A1 - Granacher, Urs A1 - Kraemer, William A1 - Izquierdo, Mikel T1 - Methodological characteristics and future directions for plyometric jump training research BT - a scoping review JF - Sports medicine N2 - 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. Y1 - 2018 U6 - https://doi.org/10.1007/s40279-018-0870-z SN - 0112-1642 SN - 1179-2035 VL - 48 IS - 5 SP - 1059 EP - 1081 PB - Springer CY - Northcote ER - TY - JOUR A1 - Fernandez-Fernandez, Jaime A1 - Granacher, Urs A1 - Martinez-Martin, Isidoro A1 - Garcia-Tormo, José Vicente A1 - Herrero-Molleda, Alba A1 - Barbado, David A1 - García López, Juan T1 - Physical fitness and throwing speed in U13 versus U15 male handball players JF - BMC Sports Science, Medicine and Rehabilitation N2 - 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. KW - Overhead athletes KW - Shoulder KW - Injury risk KW - Sport-specific performance Y1 - 2022 U6 - https://doi.org/10.1186/s13102-022-00507-0 SN - 1758-2555 VL - 14 PB - Springer CY - London ER - TY - JOUR A1 - Prieske, Olaf A1 - Dalager, Tina A1 - Looks, Vanessa A1 - Golle, Kathleen A1 - Granacher, Urs T1 - Physical fitness and psycho-cognitive performance in the young and middle-aged workforce with primarily physical versus mental work demands JF - Journal of public health : from theory to practice : official organ of the Deutscher Verband für Gesundheitswissenschaften Public Health e.V. (DVGPH) N2 - 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. KW - Core strength KW - Endurance KW - Stress KW - Work ability KW - Association Y1 - 2019 U6 - https://doi.org/10.1007/s10389-019-01099-9 SN - 2198-1833 SN - 1613-2238 VL - 29 IS - 1 SP - 75 EP - 84 PB - Springer CY - Berlin ; Heidelberg ER - TY - GEN A1 - Hortobágyi, Tibor A1 - Lesinski, Melanie A1 - Gäbler, Martijn A1 - VanSwearingen, Jessie M. A1 - Malatesta, Davide A1 - Granacher, Urs T1 - Effects of three types of exercise interventions on healthy old adults’ gait speed BT - a systematic review and meta-analysis T2 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe N2 - 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. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 840 KW - resistance training KW - exercise intervention KW - gait speed KW - power training KW - mobility disability Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-431150 SN - 1866-8364 ER - TY - GEN A1 - Hortobágyi, Tibor A1 - Lesinski, Melanie A1 - Fernandez‐del‐Olmo, Miguel A1 - Granacher, Urs T1 - Small and inconsistent effects of whole body vibration on athletic performance BT - a systematic review and meta-analysis T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe N2 - Purpose We quantified the acute and chronic effects of whole body vibration on athletic performance or its proxy measures in competitive and/or elite athletes. Methods Systematic literature review and meta-analysis. Results Whole body vibration combined with exercise had an overall 0.3 % acute effect on maximal voluntary leg force (−6.4 %, effect size = −0.43, 1 study), leg power (4.7 %, weighted mean effect size = 0.30, 6 studies), flexibility (4.6 %, effect size = −0.12 to 0.22, 2 studies), and athletic performance (−1.9 %, weighted mean effect size = 0.26, 6 studies) in 191 (103 male, 88 female) athletes representing eight sports (overall effect size = 0.28). Whole body vibration combined with exercise had an overall 10.2 % chronic effect on maximal voluntary leg force (14.6 %, weighted mean effect size = 0.44, 5 studies), leg power (10.7 %, weighted mean effect size = 0.42, 9 studies), flexibility (16.5 %, effect size = 0.57 to 0.61, 2 studies), and athletic performance (−1.2 %, weighted mean effect size = 0.45, 5 studies) in 437 (169 male, 268 female) athletes (overall effect size = 0.44). Conclusions Whole body vibration has small and inconsistent acute and chronic effects on athletic performance in competitive and/or elite athletes. These findings lead to the hypothesis that neuromuscular adaptive processes following whole body vibration are not specific enough to enhance athletic performance. Thus, other types of exercise programs (e.g., resistance training) are recommended if the goal is to improve athletic performance. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 627 KW - exercise KW - muscle KW - force KW - power KW - skill KW - reflex KW - endocrine KW - metabolism Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-431993 SN - 1866-8364 IS - 627 ER - TY - JOUR A1 - Muehlbauer, Thomas A1 - Granacher, Urs A1 - Borde, Ron A1 - Hortobagyi, Tibor T1 - Non-Discriminant Relationships between Leg Muscle Strength, Mass and Gait Performance in Healthy Young and Old Adults JF - Gerontology N2 - 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. KW - Body composition KW - Muscle torque KW - Walking KW - Seniors Y1 - 2017 U6 - https://doi.org/10.1159/000480150 SN - 0304-324X SN - 1423-0003 VL - 64 IS - 1 SP - 11 EP - 18 PB - Karger CY - Basel ER - TY - JOUR A1 - Brahms, Clemens Markus A1 - Hortobágyi, Tibor A1 - Kressig, Reto W. A1 - Granacher, Urs T1 - The Interaction between mobility status and exercise specificity in older adults JF - Exercise and sport sciences reviews N2 - 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. KW - exercise prescription KW - training intervention KW - walking speed KW - activities KW - of daily living KW - elderly Y1 - 2021 U6 - https://doi.org/10.1249/JES.0000000000000237 SN - 0091-6331 SN - 1538-3008 VL - 49 IS - 1 SP - 15 EP - 22 PB - Lippincott Williams & Wilkins CY - Hagerstown, Md. ER - TY - JOUR A1 - Hortobágyi, Tibor A1 - Vetrovsky, Tomas A1 - Balbim, Guilherme Moraes A1 - Sorte Silva, Narlon Cassio Boa A1 - Manca, Andrea A1 - Deriu, Franca A1 - Kolmos, Mia A1 - Kruuse, Christina A1 - Liu-Ambrose, Teresa A1 - Radak, Zsolt A1 - Vaczi, Mark A1 - Johansson, Hanna A1 - Rocha dos Santos, Paulo Cezar A1 - Franzen, Erika A1 - Granacher, Urs T1 - The impact of aerobic and resistance training intensity on markers of neuroplasticity in health and disease JF - Ageing research reviews : ARR N2 - 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. KW - Aging KW - Exercise KW - Intensity Dose -response relationship KW - Cognition motor KW - function Y1 - 2022 U6 - https://doi.org/10.1016/j.arr.2022.101698 SN - 1568-1637 SN - 1872-9649 VL - 80 PB - Elsevier CY - Clare ER - TY - JOUR A1 - Lacroix, Andre A1 - Hortobagyi, Tibor A1 - Beurskens, Rainer A1 - Granacher, Urs T1 - Effects of Supervised vs. Unsupervised Training Programs on Balance and Muscle Strength in Older Adults: A Systematic Review and Meta-Analysis JF - Sports medicine N2 - Objectives The objective of this systematic review and meta-analysis was to quantify the effectiveness of supervised vs. unsupervised balance and/or resistance training programs on measures of balance and muscle strength/ power in healthy older adults. In addition, the impact of supervision on training-induced adaptive processes was evaluated in the form of dose-response relationships by analyzing randomized controlled trials that compared supervised with unsupervised trials. Data Sources A computerized systematic literature search was performed in the electronic databases PubMed, Web of Science, and SportDiscus to detect articles examining the role of supervision in balance and/or resistance training in older adults. Study Eligibility Criteria The initially identified 6041 articles were systematically screened. Studies were included if they examined balance and/or resistance training in adults aged >= 65 years with no relevant diseases and registered at least one behavioral balance (e.g., time during single leg stance) and/or muscle strength/ power outcome (e.g., time for 5-Times-Chair-Rise-Test). Finally, 11 studies were eligible for inclusion in this meta-analysis. Study Appraisal Weighted mean standardized mean differences between subjects (SMDbs) of supervised vs. unsupervised balance/resistance training studies were calculated. The included studies were coded for the following variables: number of participants, sex, age, number and type of interventions, type of balance/strength tests, and change (%) from pre- to post-intervention values. Additionally, we coded training according to the following modalities: period, frequency, volume, modalities of supervision (i.e., number of supervised/unsupervised sessions within the supervised or unsupervised training groups, respectively). Heterogeneity was computed using I 2 and chi(2) statistics. The methodological quality of the included studies was evaluated using the Physiotherapy Evidence Database scale. Results Our analyses revealed that in older adults, supervised balance/resistance training was superior compared with unsupervised balance/resistance training in improving measures of static steady-state balance (mean SMDbs = 0.28, p = 0.39), dynamic steady-state balance (mean SMDbs = 0.35, p = 0.02), proactive balance (mean SMDbs = 0.24, p = 0.05), balance test batteries (mean SMDbs = 0.53, p = 0.02), and measures of muscle strength/power (mean SMDbs = 0.51, p = 0.04). Regarding the examined dose-response relationships, our analyses showed that a number of 10-29 additional supervised sessions in the supervised training groups compared with the unsupervised training groups resulted in the largest effects for static steady-state balance (mean SMDbs = 0.35), dynamic steady-state balance (mean SMDbs = 0.37), and muscle strength/power (mean SMDbs = 1.12). Further, >= 30 additional supervised sessions in the supervised training groups were needed to produce the largest effects on proactive balance (mean SMDbs = 0.30) and balance test batteries (mean SMDbs = 0.77). Effects in favor of supervised programs were larger for studies that did not include any supervised sessions in their unsupervised programs (mean SMDbs: 0.28-1.24) compared with studies that implemented a few supervised sessions in their unsupervised programs (e.g., three supervised sessions throughout the entire intervention program; SMDbs: -0.06 to 0.41). Limitations The present findings have to be interpreted with caution because of the low number of eligible studies and the moderate methodological quality of the included studies, which is indicated by a median Physiotherapy Evidence Database scale score of 5. Furthermore, we indirectly compared dose-response relationships across studies and not from single controlled studies. Conclusions Our analyses suggest that supervised balance and/or resistance training improved measures of balance and muscle strength/power to a greater extent than unsupervised programs in older adults. Owing to the small number of available studies, we were unable to establish a clear dose-response relationship with regard to the impact of supervision. However, the positive effects of supervised training are particularly prominent when compared with completely unsupervised training programs. It is therefore recommended to include supervised sessions (i.e., two out of three sessions/week) in balance/resistance training programs to effectively improve balance and muscle strength/power in older adults. Y1 - 2017 U6 - https://doi.org/10.1007/s40279-017-0747-6 SN - 0112-1642 SN - 1179-2035 VL - 47 SP - 2341 EP - 2361 PB - Springer CY - Northcote ER - TY - JOUR A1 - Prieske, Olaf A1 - Dalager, Tina A1 - Herz, Michael A1 - Hortobagyi, Tibor A1 - Sjogaard, Gisela A1 - Sogaard, Karen A1 - Granacher, Urs T1 - Effects of Physical Exercise Training in the Workplace on Physical Fitness: A Systematic Review and Meta-analysis JF - Sports medicine N2 - Background There is evidence that physical exercise training (PET) conducted at the workplace is effective in improving physical fitness and thus health. However, there is no current systematic review available that provides high-level evidence regarding the effects of PET on physical fitness in the workforce. Objectives To quantify sex-, age-, and occupation type-specific effects of PET on physical fitness and to characterize dose-response relationships of PET modalities that could maximize gains in physical fitness in the working population. Data Sources A computerized systematic literature search was conducted in the databases PubMed and Cochrane Library (2000-2019) to identify articles related to PET in workers. Study Eligibility Criteria Only randomized controlled trials with a passive control group were included if they investigated the effects of PET programs in workers and tested at least one fitness measure. Study Appraisal and Synthesis Methods Weighted mean standardised mean differences (SMDwm) were calculated using random effects models. A multivariate random effects meta-regression was computed to explain the influence of key training modalities (e.g., training frequency, session duration, intensity) on the effectiveness of PET on measures of physical fitness. Further, subgroup univariate analyses were computed for each training modality. Additionally, methodological quality of the included studies was rated with the help of the Physiotherapy Evidence Database (PEDro) Scale. Results Overall, 3423 workers aged 30-56 years participated in 17 studies (19 articles) that were eligible for inclusion. Methodological quality of the included studies was moderate with a median PEDro score of 6. Our analyses revealed significant, small-sized effects of PET on cardiorespiratory fitness (CRF), muscular endurance, and muscle power (0.29 <= SMDwm <= 0.48). Medium effects were found for CRF and muscular endurance in younger workers (<= 45 years) (SMDwm = 0.71) and white-collar workers (SMDwm = 0.60), respectively. Multivariate random effects meta-regression for CRF revealed that none of the examined training modalities predicted the effects of PET on CRF (R-2 = 0). Independently computed subgroup analyses showed significant PET effects on CRF when conducted for 9-12 weeks (SMDwm = 0.31) and for 17-20 weeks (SMDwm = 0.74). Conclusions PET effects on physical fitness in healthy workers are moderated by age (CRF) and occupation type (muscular endurance). Further, independently computed subgroup analyses indicated that the training period of the PET programs may play an important role in improving CRF in workers. Y1 - 2019 U6 - https://doi.org/10.1007/s40279-019-01179-6 SN - 0112-1642 SN - 1179-2035 VL - 49 IS - 12 SP - 1903 EP - 1921 PB - Springer CY - Northcote ER - TY - JOUR A1 - Hortobagyi, Tibor A1 - Lesinski, Melanie A1 - Fernandez-del-Olmo, Miguel A1 - Granacher, Urs T1 - Small and inconsistent effects of whole body vibration on athletic performance: a systematic review and meta-analysis JF - European journal of applied physiology N2 - We quantified the acute and chronic effects of whole body vibration on athletic performance or its proxy measures in competitive and/or elite athletes. Systematic literature review and meta-analysis. Whole body vibration combined with exercise had an overall 0.3 % acute effect on maximal voluntary leg force (-6.4 %, effect size = -0.43, 1 study), leg power (4.7 %, weighted mean effect size = 0.30, 6 studies), flexibility (4.6 %, effect size = -0.12 to 0.22, 2 studies), and athletic performance (-1.9 %, weighted mean effect size = 0.26, 6 studies) in 191 (103 male, 88 female) athletes representing eight sports (overall effect size = 0.28). Whole body vibration combined with exercise had an overall 10.2 % chronic effect on maximal voluntary leg force (14.6 %, weighted mean effect size = 0.44, 5 studies), leg power (10.7 %, weighted mean effect size = 0.42, 9 studies), flexibility (16.5 %, effect size = 0.57 to 0.61, 2 studies), and athletic performance (-1.2 %, weighted mean effect size = 0.45, 5 studies) in 437 (169 male, 268 female) athletes (overall effect size = 0.44). Whole body vibration has small and inconsistent acute and chronic effects on athletic performance in competitive and/or elite athletes. These findings lead to the hypothesis that neuromuscular adaptive processes following whole body vibration are not specific enough to enhance athletic performance. Thus, other types of exercise programs (e.g., resistance training) are recommended if the goal is to improve athletic performance. KW - Exercise KW - Muscle KW - Force KW - Power KW - Skill KW - Reflex KW - Endocrine KW - Metabolism Y1 - 2015 U6 - https://doi.org/10.1007/s00421-015-3194-9 SN - 1439-6319 SN - 1439-6327 VL - 115 IS - 8 SP - 1605 EP - 1625 PB - Springer CY - New York ER - TY - JOUR A1 - Jararnezhadgero, AmirAli A1 - Mamashli, Elaheh A1 - Granacher, Urs T1 - An Endurance-Dominated Exercise Program Improves Maximum Oxygen Consumption, Ground Reaction Forces, and Muscle Activities in Patients With Moderate Diabetic Neuropathy JF - Frontiers in physiology / Frontiers Research Foundation N2 - 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. KW - oxygen consumption KW - kinetics KW - electromyography KW - diabetic KW - gait Y1 - 2021 U6 - https://doi.org/10.3389/fphys.2021.654755 SN - 1664-042X VL - 12 SP - 1 EP - 15 PB - Frontiers Research Foundation CY - Lausanne, Schweiz ER - TY - JOUR A1 - Prieske, Olaf A1 - Mühlbauer, Thomas A1 - Müller, Steffen A1 - Krüger, Tom A1 - Kibele, Armin A1 - Behm, David George A1 - Granacher, Urs T1 - Effects of surface instability on neuromuscular performance during drop jumps and landings JF - European journal of applied physiology N2 - The purpose of this study was to investigate the effects of surface instability on measures of performance and activity of leg and trunk muscles during drop jumps and landings. Drop jumps and landings were assessed on a force plate under stable and unstable (balance pad on top of the force plate) conditions. Performance measures (contact time, jump height, peak ground reaction force) and electromyographic (EMG) activity of leg and trunk muscles were tested in 27 subjects (age 23 +/- A 3 years) during different time intervals (preactivation phase, braking phase, push-off phase). The performance of drop jumps under unstable compared to stable conditions produced a decrease in jump height (9 %, p < 0.001, f = 0.92) and an increase in peak ground reaction force (5 %, p = 0.022, f = 0.72), and time for braking phase (12 %, p < 0.001, f = 1.25). When performing drop jumps on unstable compared to stable surfaces, muscle activity was reduced in the lower extremities during the preactivation, braking and push-off phases (11-25 %, p < 0.05, 0.48 a parts per thousand currency sign f a parts per thousand currency sign 1.23). Additionally, when landing on unstable compared to stable conditions, reduced lower limb muscle activities were observed during the preactivation phase (7-60 %, p < 0.05, 0.50 a parts per thousand currency sign f a parts per thousand currency sign 3.62). Trunk muscle activity did not significantly differ between the test conditions for both jumping and landing tasks. The present findings indicate that modified feedforward mechanisms in terms of lower leg muscle activities during the preactivation phase and/or possible alterations in leg muscle activity shortly after ground contact (i.e., braking phase) are responsible for performance decrements during jumping on unstable surfaces. KW - Stretch-shortening cycle KW - Trunk muscle strength KW - Jump height KW - Electromyography Y1 - 2013 U6 - https://doi.org/10.1007/s00421-013-2724-6 SN - 1439-6319 SN - 1439-6327 VL - 113 IS - 12 SP - 2943 EP - 2951 PB - Springer CY - New York ER - TY - JOUR A1 - Arazi, Hamid A1 - Asadi, Abbas A1 - Khalkhali, Farhood A1 - Boullosa, Daniel A1 - Hackney, Anthony C. A1 - Granacher, Urs A1 - Zouhal, Hassane T1 - Association Between the Acute to Chronic Workload Ratio and Injury Occurrence in Young Male Team Soccer Players BT - A Preliminary Study N2 - This study aimed to investigate the relationship between the acute to chronic workload ratio (ACWR), based upon participant session rating of perceived exertion (sRPE), using two models [(1) rolling averages (ACWRRA); and (2) exponentially weighted moving averages (ACWREWMA)] and the injury rate in young male team soccer players aged 17.1 ± 0.7 years during a competitive mesocycle. Twenty-two players were enrolled in this study and performed four training sessions per week with 2 days of recovery and 1 match day per week. During each training session and each weekly match, training time and sRPE were recorded. In addition, training impulse (TRIMP), monotony, and strain were subsequently calculated. The rate of injury was recorded for each soccer player over a period of 4 weeks (i.e., 28 days) using a daily questionnaire. The results showed that over the course of the study, the number of non-contact injuries was significantly higher than that for contact injuries (2.5 vs. 0.5, p = 0.01). There were also significant positive correlations between sRPE and training time (r = 0.411, p = 0.039), ACWRRA (r = 0.47, p = 0.049), and ACWREWMA (r = 0.51, p = 0.038). In addition, small-to-medium correlations were detected between ACWR and non-contact injury occurrence (ACWRRA, r = 0.31, p = 0.05; ACWREWMA, r = 0.53, p = 0.03). Explained variance (r²) for non-contact injury was significantly greater using the ACWREWMA model (ranging between 21 and 52%) compared with ACWRRA (ranging between 17 and 39%). In conclusion, the results of this study showed that the ACWREWMA model is more sensitive than ACWRRA to identify non-contact injury occurrence in male team soccer players during a short period in the competitive season. KW - training load KW - rate of perceived exertion KW - rolling averages KW - weighted moving averages KW - football Y1 - 2020 U6 - https://doi.org/10.3389/fphys.2020.00608 SN - 1664-042X VL - 11 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Ahmadi, Hamid A1 - Herat, Nehara A1 - Alizadeh, Shahab A1 - Button, Duane C. A1 - Granacher, Urs A1 - Behm, David G. T1 - Effect of an inverted seated position with upper arm blood flow restriction on measures of elbow flexors neuromuscular performance JF - PLOS ONE / Public Library of Science N2 - 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. Y1 - 2021 U6 - https://doi.org/10.1371/journal.pone.0245311 SN - 1932-6203 VL - 16 IS - 5 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Lesinski, Melanie A1 - Herz, Michael A1 - Schmelcher, Alina A1 - Granacher, Urs T1 - Effects of resistance training on physical fitness in healthy children and adolescents BT - an umbrella review JF - Sports medicine N2 - 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. Y1 - 2020 U6 - https://doi.org/10.1007/s40279-020-01327-3 SN - 0112-1642 SN - 1179-2035 VL - 50 IS - 11 SP - 1901 EP - 1928 PB - Springer CY - Northcote ER - TY - JOUR A1 - Jafarnezhadgero, Amir Ali A1 - Madadi-Shad, Morteza A1 - Alavi-Mehr, Seyed Majid A1 - Granacher, Urs T1 - The long-term use of foot orthoses affects walking kinematics and kinetics of children with flexible flat feet BT - A randomized controlled trial JF - PLoS ONE N2 - Background Due to inconclusive evidence on the effects of foot orthoses treatment on lower limb kinematics and kinetics in children, studies are needed that particularly evaluate the long-term use of foot orthoses on lower limb alignment during walking. Thus, the main objective of this study was to evaluate the effects of long-term treatment with arch support foot orthoses versus a sham condition on lower extremity kinematics and kinetics during walking in children with flexible flat feet. Methods Thirty boys aged 8–12 years with flexible flat feet participated in this study. While the experimental group (n = 15) used medial arch support foot orthoses during everyday activities over a period of four months, the control group (n = 15) received flat 2-mm-thick insoles (i.e., sham condition) for the same time period. Before and after the intervention period, walking kinematics and ground reaction forces were collected. Results Significant group by time interactions were observed during walking at preferred gait speed for maximum ankle eversion, maximum ankle internal rotation angle, minimum knee abduction angle, maximum knee abduction angle, maximum knee external rotation angle, maximum knee internal rotation angle, maximum hip extension angle, and maximum hip external rotation angle in favor of the foot orthoses group. In addition, statistically significant group by time interactions were detected for maximum posterior, and vertical ground reaction forces in favor of the foot orthoses group. Conclusions The long-term use of arch support foot orthoses proved to be feasible and effective in boys with flexible flat feet to improve lower limb alignment during walking. KW - lower-extremity kinematics KW - medial longitudinal arch KW - limb overuse conditions KW - ground reaction force KW - low-back-pain KW - knee osteoarthritis KW - calcaneal eversion KW - standing position KW - pelvic alignment KW - sex-differences Y1 - 2018 U6 - https://doi.org/10.1371/journal.pone.0205187 SN - 1932-6203 VL - 13 IS - 10 SP - 1 EP - 19 PB - Public Library of Science CY - San Francisco ER - TY - JOUR A1 - Makhlouf, Issam A1 - Chaouachi, Anis A1 - Chaouachi, Mehdi A1 - Othman, Aymen Ben A1 - Granacher, Urs T1 - Combination of Agility and Plyometric Training Provides Similar Training Benefits as Combined Balance and Plyometric Training in Young Soccer Players JF - Frontiers in Physiology N2 - Introduction: Studies that combined balance and resistance training induced larger performance improvements compared with single mode training. Agility exercises contain more dynamic and sport-specific movements compared with balance training. Thus, the purpose of this study was to contrast the effects of combined balance and plyometric training with combined agility and plyometric training and an active control on physical fitness in youth. Methods: Fifty-seven male soccer players aged 10–12 years participated in an 8-week training program (2 × week). They were randomly assigned to a balance-plyometric (BPT: n = 21), agility-plyometric (APT: n = 20) or control group (n = 16). Measures included proxies of muscle power [countermovement jump (CMJ), triple-hop-test (THT)], muscle strength [reactive strength index (RSI), maximum voluntary isometric contraction (MVIC) of handgrip, back extensors, knee extensors], agility [4-m × 9-m shuttle run, Illinois change of direction test (ICODT) with and without the ball], balance (Standing Stork, Y-Balance), and speed (10–30 m sprints). Results: Significant time × group interactions were found for CMJ, hand grip MVIC force, ICODT without a ball, agility (4 m × 9 m), standing stork balance, Y-balance, 10 and 30-m sprint. The APT pre- to post-test measures displayed large ES improvements for hand grip MVIC force, ICODT without a ball, agility test, CMJ, standing stork balance test, Y-balance test but only moderate ES improvements with the 10 and 30 m sprints. The BPT group showed small (30 m sprint), moderate (hand grip MVIC, ICODTwithout a ball) and large ES [agility (4 m × 9 m) test, CMJ, standing stork balance test, Y-balance] improvements, respectively. Conclusion: In conclusion, both training groups provided significant improvements in all measures. It is recommended that youth incorporate balance exercises into their training and progress to agility with their strength and power training. KW - jump training KW - plyometrics KW - change of direction KW - adolescents KW - football Y1 - 2018 U6 - https://doi.org/10.3389/fphys.2018.01611 SN - 1664-042X VL - 9 SP - 1 EP - 17 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Arazi, Hamid A1 - Asadi, Abbas A1 - Khalkhali, Farhood A1 - Boullosa, Daniel A1 - Hackney, Anthony C. A1 - Granacher, Urs A1 - Zouhal, Hassane T1 - Association Between the Acute to Chronic Workload Ratio and Injury Occurrence in Young Male Team Soccer Players BT - A Preliminary Study JF - Frontiers in Physiology N2 - This study aimed to investigate the relationship between the acute to chronic workload ratio (ACWR), based upon participant session rating of perceived exertion (sRPE), using two models [(1) rolling averages (ACWRRA); and (2) exponentially weighted moving averages (ACWREWMA)] and the injury rate in young male team soccer players aged 17.1 ± 0.7 years during a competitive mesocycle. Twenty-two players were enrolled in this study and performed four training sessions per week with 2 days of recovery and 1 match day per week. During each training session and each weekly match, training time and sRPE were recorded. In addition, training impulse (TRIMP), monotony, and strain were subsequently calculated. The rate of injury was recorded for each soccer player over a period of 4 weeks (i.e., 28 days) using a daily questionnaire. The results showed that over the course of the study, the number of non-contact injuries was significantly higher than that for contact injuries (2.5 vs. 0.5, p = 0.01). There were also significant positive correlations between sRPE and training time (r = 0.411, p = 0.039), ACWRRA (r = 0.47, p = 0.049), and ACWREWMA (r = 0.51, p = 0.038). In addition, small-to-medium correlations were detected between ACWR and non-contact injury occurrence (ACWRRA, r = 0.31, p = 0.05; ACWREWMA, r = 0.53, p = 0.03). Explained variance (r 2) for non-contact injury was significantly greater using the ACWREWMA model (ranging between 21 and 52%) compared with ACWRRA (ranging between 17 and 39%). In conclusion, the results of this study showed that the ACWREWMA model is more sensitive than ACWRRA to identify non-contact injury occurrence in male team soccer players during a short period in the competitive season. KW - training load KW - rate of perceived exertion KW - rolling averages KW - weighted moving averages KW - football Y1 - 2020 U6 - https://doi.org/10.3389/fphys.2020.00995 SN - 1664-042X VL - 11 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Helm, Norman A1 - Prieske, Olaf A1 - Mühlbauer, Thomas A1 - Krüger, Tom A1 - Granacher, Urs T1 - Effects of judo-specific resistance training on kinetic and electromyographic parameters of pulling exercises in judo athletes T1 - Effekte eines judospezifischen Messplatztrainings auf kinetische und elektromyografische Parameter des Anreißens bei Wurfeingangsbewegungen von Judoka JF - Sportverletzung, Sportschaden : Grundlagen, Prävention, Rehabilitation N2 - Background In judo, rapid force production during pulling movements is an important component of athletic performance, which is why this capacity needs to be specifically exercised in judo. This study aimed at examining the effects of a judo-specific resistance training program using a judo ergometer system (PTJ) versus a traditional resistance training regime using a partner (PTP) on kinetics and muscle activity of judo-specific pulling exercises. Method Twenty-four male judo athletes (age: 22 +/- 4 years, training experience: 15 +/- 3 years) were randomly assigned to two groups. In a crossover design, the first group completed a 4-week PTJ followed by four weeks of PTP (each with three sessions per week). The second group conducted PTP prior to PTJ. PTJ and PTP were completed in addition to regular training. Before, 4 weeks and 8 weeks after training, tests were conducted to assess judo-specific pulling kinetics (i.e. maximal force, rate of force development [RFD], mechanical work) and electromyographic (EMG) shoulder/trunk muscle activity (i.e. biceps brachii muscle, deltoid muscle, trapezius muscle, erector spinae muscle) during pulling movements using a judo ergometer as well as unspecific strength tests (i.e. bench-pull, pull-ups). Results The statistical analysis revealed that in both groups ergometer pulling kinetics (p<.05, 0.83 <= d <= 1.77) and EMG activity (p<.05; 1.07 <= d <= 2.25) were significantly enhanced following 8 weeks of training. In addition, significantly larger gains in RFD, mechanical work, and EMG activity (i.e. deltoid muscle, erector spinae muscle, trapezius muscle) were found following PTJ compared to PTP (p<.05, 1.25 <= d <= 2.79). No significant enhancements were observed with the unspecific strength tests. Conclusion Our findings indicate that PTJ is superior to PTP regarding training-induced improvements in force production and muscle activity during judo-specific pulling exercises. Performance enhancements may partly be attributed to neural adaptations. No transfer effects on unspecific strength tests were detected following PTJ and PTP. N2 - Hintergrund Schnellkräftige Wurfeingangsbewegungen stellen im Judo entscheidende Voraussetzungen für den Wettkampferfolg dar, weshalb das Training der Anrissbewegung ein zentrales Element des judospezifischen Trainings darstellt. Das Ziel der Studie bestand darin, die Effekte eines Anrisstrainings mit einem Judoergometer-System (ATJ) gegenüber einem tradierten Anrisstraining mit Partner (ATP) auf kinetische und elektromyografische Parameter des Anreißens bei Wurfeingangsbewegungen von Judoka zu untersuchen. Methode Männliche leistungsorientierte Judoka (N = 24, Alter: 22 ± 4 Jahre; Trainingserfahrung: 15 ± 3 Jahre) wurden randomisiert in zwei Gruppen aufgeteilt. Im Crossover-Design absolvierte die erste Gruppe über vier Wochen ein ATJ gefolgt von vier Wochen ATP (je 3x/ Woche). Die zweite Gruppe führte beide Trainingsvarianten in umgekehrter Reihenfolge durch. ATJ und ATP wurden zusätzlich zum bestehenden Training absolviert. Vor dem Training sowie nach vier und nach acht Wochen Training wurden Tests zur Erfassung kinetischer Parameter (dynamisch-realisierte Maximalkraft, Explosivkraft, mechanische Arbeit) und elektromyografischer (EMG) Schulter-/ Rumpfmuskelaktivitäten (M. biceps brachii, M. deltoideus, M. trapezius, M. erector spinae) für die Hub- und Zugarmseite bei Wurfeingangsbewegungen am Judoergometer sowie sportartunspezifische Krafttests (d. h. Liegend-Anreißen, Klimmziehen) durchgeführt. Ergebnisse Die Ergebnisse der statistischen Analyse ergaben über den gesamten Interventionszeitraum (8 Wochen) für beide Trainingsgruppen signifikante Verbesserungen der kinetischen Parameter (p <,05; 0,83 ≤d≤ 1,77) und EMG-Aktivitäten (p <,05; 1,07 ≤d≤ 2,25). Darüber hinaus zeigten sich größere Zuwachsraten in der Explosivkraft, der mechanischen Arbeit und den Schulter-/Rumpfmuskelaktivitäten (M. deltoideus, M. erector spinae, M. trapezius) zugunsten von ATJ im Vergleich zu ATP (p <,05; 1,25 ≤d≤ 2,79). Für die sportartunspezifischen Kraftwerte wurden keine signifikanten Veränderungen festgestellt. Schlussfolgerung Die vorliegenden Ergebnisse zeigen, dass ATJ gegenüber ATP größere Steigerungsraten von kinetischen und elektromyografischen Parametern des Anreißens bei Wurfeingangsbewegungen von Judoka bewirkt. Die trainingsbedingten Leistungssteigerungen scheinen zumindest teilweise auf neuronalen Anpassungen zu beruhen. KW - combat sport KW - athletic performance KW - specific strength training KW - surface electromyography KW - Kampfsport KW - sportliche Leistung KW - spezifisches Krafttraining KW - Oberflächenelektromyografie Y1 - 2018 U6 - https://doi.org/10.1055/s-0043-122781 SN - 0932-0555 SN - 1439-1236 VL - 32 IS - 2 SP - 134 EP - 142 PB - Thieme CY - Stuttgart ER - TY - JOUR A1 - Gäbler, Martijn A1 - Prieske, Olaf A1 - Hortobagyi, Tibor A1 - Granacher, Urs T1 - The Effects of Concurrent Strength and Endurance Training on Physical Fitness and Athletic Performance in Youth BT - A Systematic Review and Meta-Analysis JF - Frontiers in Physiology N2 - 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 V°O2, 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. KW - child KW - adolescent KW - muscle strength KW - cardiorespiratory fitness KW - physical conditioning human KW - resistance training KW - youth sports Y1 - 2018 U6 - https://doi.org/10.3389/fphys.2018.01057 SN - 1664-042X VL - 9 SP - 1 EP - 13 PB - Frontiers Research Foundation CY - Lausanne ER - TY - GEN A1 - Gäbler, Martijn A1 - Berberyan, Hermine S. A1 - Prieske, Olaf A1 - Elferink-Gemser, Marije Titia A1 - Hortobagyi, Tibor A1 - Warnke, Torsten A1 - Granacher, Urs T1 - Strength Training Intensity and Volume Affect Performance of Young Kayakers/Canoeists T2 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe N2 - 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). T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 744 KW - youth sports KW - water sports KW - exercise test KW - athletic performance KW - anthropometry Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-542283 SN - 1866-8364 SP - 1 EP - 10 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - GEN A1 - Prieske, Olaf A1 - Maffiuletti, Nicola A. A1 - Granacher, Urs T1 - Postactivation Potentiation of the Plantar Flexors Does Not Directly Translate to Jump Performance in Female Elite Young Soccer Players T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe N2 - Background: Infection with human immunodeficiency virus (HIV) affects muscle mass, altering independent activities of people living with HIV (PLWH). Resistance training alone (RT) or combined with aerobic exercise (AE) is linked to improved muscle mass and strength maintenance in PLWH. These exercise benefits have been the focus of different meta-analyses, although only a limited number of studies have been identified up to the year 2013/4. An up-to-date systematic review and meta-analysis concerning the effect of RT alone or combined with AE on strength parameters and hormones is of high value, since more and recent studies dealing with these types of exercise in PLWH have been published. Methods: Randomized controlled trials evaluating the effects of RT alone, AE alone or the combination of both (AERT) on PLWH was performed through five web-databases up to December 2017. Risk of bias and study quality was attained using the PEDro scale. Weighted mean difference (WMD) from baseline to post-intervention changes was calculated. The I2 statistics for heterogeneity was calculated. Results: Thirteen studies reported strength outcomes. Eight studies presented a low risk of bias. The overall change in upper body strength was 19.3 Kg (95% CI: 9.8±28.8, p< 0.001) after AERT and 17.5 Kg (95% CI: 16±19.1, p< 0.001) for RT. Lower body change was 29.4 Kg (95% CI: 18.1±40.8, p< 0.001) after RT and 10.2 Kg (95% CI: 6.7±13.8, p< 0.001) for AERT. Changes were higher after controlling for the risk of bias in upper and lower body strength and for supervised exercise in lower body strength. A significant change towards lower levels of IL-6 was found (-2.4 ng/dl (95% CI: -2.6, -2.1, p< 0.001). Conclusion: Both resistance training alone and combined with aerobic exercise showed a positive change when studies with low risk of bias and professional supervision were analyzed, improving upper and, more critically, lower body muscle strength. Also, this study found that exercise had a lowering effect on IL-6 levels in PLWH. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 483 KW - sensorimotor training KW - conditioning activity KW - twitch torque KW - power KW - soccer Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-420558 SN - 1866-8364 IS - 483 ER - TY - GEN A1 - Gschwind, Yves J. A1 - Bridenbaugh, Stephanie A. A1 - Reinhard, Sarah A1 - Granacher, Urs A1 - Monsch, Andreas U. A1 - Kressig, Reto W. T1 - Ginkgo biloba special extract LI 1370 improves dual-task walking in patients with MCI BT - a randomised, double-blind, placebo-controlled exploratory study T2 - Postprints der Universität Potsdam : Mathematisch Naturwissenschaftliche Reihe N2 - Background In patients with mild cognitive impairment (MCI), gait instability, particularly in dual-task situations, has been associated with impaired executive function and an increased fall risk. Ginkgo biloba extract (GBE) could be an effective mean to improve gait stability. Aims This study investigated the effect of GBE on spatiotemporal gait parameters of MCI patients while walking under single and dual-task conditions. Methods Fifty patients aged 50-85 years with MCI and associated dual-task-related gait impairment participated in this randomised, double-blind, placebo-controlled, exploratory phase IV drug trial. Intervention group (IG) patients received GBE (Symfona (R) forte 120 mg) twice-daily for 6 months while control group (CG) patients received placebo capsules. A 6-month open-label phase with identical GBE dosage followed. Gait was quantified at months 0, 3, 6 and 12. Results After 6 months, dual-task-related cadence increased in the IG compared to the CG (p = 0.019, d = 0.71). No significant changes, but GBE-associated numerical non-significant trends were found after 6-month treatment for dual-task-related gait velocity and stride time variability. Discussion Findings suggest that 120 mg of GBE twice-daily for at least 6 months may improve dual-task-related gait performance in patients with MCI. Conclusions The observed gait improvements add to the understanding of the self-reported unspecified improvements among MCI patients when treated with standardised GBE. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 870 KW - gait KW - walking KW - executive function KW - mild cognitive impairment KW - cognitive enhancer KW - Ginkgo biloba extract Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-434796 SN - 1866-8372 IS - 870 SP - 609 EP - 619 ER - TY - GEN A1 - Zinke, Fridolin A1 - Warnke, Torsten A1 - Gäbler, Martijn A1 - Granacher, Urs T1 - Effects of Isokinetic Training on Trunk Muscle Fitness and Body Composition in World-Class Canoe Sprinters T2 - Postprints der Universität Potsdam Humanwissenschaftliche Reihe N2 - In canoe sprint, the trunk muscles play an important role in stabilizing the body in an unstable environment (boat) and in generating forces that are transmitted through the shoulders and arms to the paddle for propulsion of the boat. Isokinetic training is well suited for sports in which propulsion is generated through water resistance due to similarities in the resistive mode. Thus, the purpose of this study was to determine the effects of isokinetic training in addition to regular sport-specific training on trunk muscular fitness and body composition in world-class canoeists and to evaluate associations between trunk muscular fitness and canoe-specific performance. Nine world-class canoeists (age: 25.6 ± 3.3 years; three females; four world champions; three Olympic gold medalists) participated in an 8-week progressive isokinetic training with a 6-week block “muscle hypertrophy” and a 2-week block “muscle power.” Pre- and post-tests included the assessment of peak isokinetic torque at different velocities in concentric (30 and 140∘s-1) and eccentric (30 and 90∘s-1) mode, trunk muscle endurance, and body composition (e.g., body fat, segmental lean mass). Additionally, peak paddle force was assessed in the flume at a water current of 3.4 m/s. Significant pre-to-post increases were found for peak torque of the trunk rotators at 30∘s-1 (p = 0.047; d = 0.4) and 140∘s-1 (p = 0.014; d = 0.7) in concentric mode. No significant pre-to-post changes were detected for eccentric trunk rotator torque, trunk muscle endurance, and body composition (p > 0.148). Significant medium-to-large correlations were observed between concentric trunk rotator torque but not trunk muscle endurance and peak paddle force, irrespective of the isokinetic movement velocity (all r ≥ 0.886; p ≤ 0.008). Isokinetic trunk rotator training is effective in improving concentric trunk rotator strength in world-class canoe sprinters. It is recommended to progressively increase angular velocity from 30∘s-1 to 140∘s-1 over the course of the training period. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 536 KW - peak torque KW - canoe racing KW - core strength KW - sport-specific performance KW - elite athletes Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-424898 SN - 1866-8364 IS - 536 ER - TY - GEN A1 - Peitz, Matti A1 - Behringer, Michael A1 - Granacher, Urs T1 - A systematic review on the effects of resistance and plyometric training on physical fitness in youth BT - What do comparative studies tell us? T2 - Postprints der Universität Potsdam Humanwissenschaftliche Reihe N2 - Introduction To date, several meta-analyses clearly demonstrated that resistance and plyometric training are effective to improve physical fitness in children and adolescents. However, a methodological limitation of meta-analyses is that they synthesize results from different studies and hence ignore important differences across studies (i.e., mixing apples and oranges). Therefore, we aimed at examining comparative intervention studies that assessed the effects of age, sex, maturation, and resistance or plyometric training descriptors (e.g., training intensity, volume etc.) on measures of physical fitness while holding other variables constant. Methods To identify relevant studies, we systematically searched multiple electronic databases (e.g., PubMed) from inception to March 2018. We included resistance and plyometric training studies in healthy young athletes and non-athletes aged 6 to 18 years that investigated the effects of moderator variables (e.g., age, maturity, sex, etc.) on components of physical fitness (i.e., muscle strength and power). Results Our systematic literature search revealed a total of 75 eligible resistance and plyometric training studies, including 5,138 participants. Mean duration of resistance and plyometric training programs amounted to 8.9 ± 3.6 weeks and 7.1±1.4 weeks, respectively. Our findings showed that maturation affects plyometric and resistance training outcomes differently, with the former eliciting greater adaptations pre-peak height velocity (PHV) and the latter around- and post-PHV. Sex has no major impact on resistance training related outcomes (e.g., maximal strength, 10 repetition maximum). In terms of plyometric training, around-PHV boys appear to respond with larger performance improvements (e.g., jump height, jump distance) compared with girls. Different types of resistance training (e.g., body weight, free weights) are effective in improving measures of muscle strength (e.g., maximum voluntary contraction) in untrained children and adolescents. Effects of plyometric training in untrained youth primarily follow the principle of training specificity. Despite the fact that only 6 out of 75 comparative studies investigated resistance or plyometric training in trained individuals, positive effects were reported in all 6 studies (e.g., maximum strength and vertical jump height, respectively). Conclusions The present review article identified research gaps (e.g., training descriptors, modern alternative training modalities) that should be addressed in future comparative studies. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 498 KW - young soccer players KW - randomized controlled-trial KW - school baseball players KW - whole-body vibratoin KW - rugby league players KW - of-direction speed KW - endurance performance KW - muscular strength KW - motor-performance Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-422201 SN - 1866-8364 IS - 498 ER - TY - GEN A1 - Jafarnezhadgero, Amir Ali A1 - Fatollahi, Amir A1 - Amirzadeh, Nasrin A1 - Siahkouhian, Marefat A1 - Granacher, Urs T1 - Ground Reaction Forces and Muscle Activity While Walking on Sand versus Stable Ground in Individuals with Pronated Feet Compared with Healthy Controls T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe N2 - Background Sand is an easy-to-access, cost-free resource that can be used to treat pronated feet (PF). Therefore, the aims of this study were to contrast the effects of walking on stable ground versus walking on sand on ground reaction forces (GRFs) and electromyographic (EMG) activity of selected lower limb muscles in PF individuals compared with healthy controls. Methods Twenty-nine controls aged 22.2±2.5 years and 30 PF individuals aged 22.2±1.9 years were enrolled in this study. Participants walked at preferred speed and in randomized order over level ground and sand. A force plate was included in the walkway to collect GRFs. Muscle activities were recorded using EMG system. Results No statistically significant between-group differences were found in preferred walking speed when walking on stable ground (PF: 1.33±0.12 m/s; controls: 1.35±0.14 m/s; p = 0.575; d = 0.15) and sand (PF: 1.19±0.11 m/s; controls: 1.23±0.18 m/s; p = 0.416; d = 0.27). Irrespective of the group, walking on sand (1.21±0.15 m/s) resulted in significantly lower gait speed compared with stable ground walking (1.34±0.13 m/s) (p<0.001; d = 0.93). Significant main effects of “surface” were found for peak posterior GRFs at heel contact, time to peak for peak lateral GRFs at heel contact, and peak anterior GRFs during push-off (p<0.044; d = 0.27–0.94). Pair-wise comparisons revealed significantly smaller peak posterior GRFs at heel contact (p = 0.005; d = 1.17), smaller peak anterior GRFs during push-off (p = 0.001; d = 1.14), and time to peak for peak lateral GRFs (p = 0.044; d = 0.28) when walking on sand. No significant main effects of “group” were observed for peak GRFs and their time to peak (p>0.05; d = 0.06–1.60). We could not find any significant group by surface interactions for peak GRFs and their time to peak. Significant main effects of “surface” were detected for anterior-posterior impulse and peak positive free moment amplitude (p<0.048; d = 0.54–0.71). Pair-wise comparisons revealed a significantly larger peak positive free moment amplitude (p = 0.010; d = 0.71) and a lower anterior-posterior impulse (p = 0.048; d = 0.38) when walking on sand. We observed significant main effects of “group” for the variable loading rate (p<0.030; d = 0.59). Pair-wise comparisons revealed significantly lower loading rates in PF compared with controls (p = 0.030; d = 0.61). Significant group by surface interactions were observed for the parameter peak positive free moment amplitude (p<0.030; d = 0.59). PF individuals exhibited a significantly lower peak positive free moment amplitude (p = 0.030, d = 0.41) when walking on sand. With regards to EMG, no significant main effects of “surface”, main effects of “group”, and group by surface interactions were observed for the recorded muscles during the loading and push-off phases (p>0.05; d = 0.00–0.53). Conclusions The observed lower velocities during walking on sand compared with stable ground were accompanied by lower peak positive free moments during the push-off phase and loading rates during the loading phase. Our findings of similar lower limb muscle activities during walking on sand compared with stable ground in PF together with lower free moment amplitudes, vertical loading rates, and lower walking velocities on sand may indicate more relative muscle activity on sand compared with stable ground. This needs to be verified in future studies. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 590 Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-441027 SN - 1866-8364 IS - 590 ER -