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 - 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 - 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 - 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 - 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 - 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 -