@article{NiehuesGerlachSallen2021,
  author    = {Niehues, Maike and Gerlach, Erin and Sallen, Jeffrey},
  title     = {Measuring dual career motivation among German student-athletes using the Student Athletes' Motivation Toward Sports and Academics Questionnaire},
  series = {German journal of exercise and sport research : Sportwissenschaft / Bundesinstitut f{\"u}r Sportwissenschaft, Deutscher Olympischer Sportbund, Deutsche Vereinigung f{\"u}r Sportwissenschaft},
  volume    = {51},
  journal   = {German journal of exercise and sport research : Sportwissenschaft / Bundesinstitut f{\"u}r Sportwissenschaft, Deutscher Olympischer Sportbund, Deutsche Vereinigung f{\"u}r Sportwissenschaft},
  number    = {3},
  publisher = {Springer},
  address   = {Berlin ; Heidelberg},
  issn      = {2509-3142},
  doi       = {10.1007/s12662-021-00723-9},
  pages     = {378 -- 383},
  year      = {2021},
  abstract  = {With the 2012 EU guidelines on dual careers (DC), DC research gained increasing awareness in Europe focussing particularly on student-athletes' motivation. The Student Athletes' Motivation toward Sports and Academics Questionnaire (SAMSAQ), arguably the most prominent instrument in this research area, has been used in various cross-cultural studies assessing DC motivation. The present investigation contributes to the cross-cultural discourse aiming to (1) adapt the SAMSAQ for the German context and adolescent secondary school student-athletes, and (2) evaluate the German pre-version. A sample of 208 student-athletes (52.4\% females, mean age = 17.4 years, 49.5\% at squad level) at three German Elite Sport Schools participated in the study. The investigation was split into two parts. First, the SAMSAQ was adapted to the German context and tested. In the second part, the first pre-version was revised. A series of exploratory factor analyses were applied to verify the factor structure of both German SAMSAQ pre-versions. Eight different factor models based on item removal were compared. Neither model demonstrated good results for the replication of previous findings or a meaningful solution in terms of content. Reasons for the deviations between the original and target SAMSAQ factor structures can be found in the different target groups and the culturally different approaches to career assistant programmes as well as in the theoretical background of the instrument. Since neither model was identified as acceptable, the findings indicate that a new instrument needs to be developed for assessing student-athletes' DC motivation along their pathways in different cross-cultural contexts.},
  language  = {en}
}
@article{PalmaMunozRamirezCampilloAzocarGallardoetal.2021,
  author    = {Palma-Mu{\~n}oz, Ignacio and Ram{\´i}rez-Campillo, Rodrigo and Azocar-Gallardo, Jairo and {\´A}lvarez, Cristian and Asadi, Abbas and Moran, Jason and Chaabene, Helmi},
  title     = {Effects of progressed and nonprogressed volume-based overload plyometric training on components of physical fitness and body composition variables in youth male basketball players},
  series = {Journal of strength and conditioning research : the research journal of the NSCA},
  volume    = {35},
  journal   = {Journal of strength and conditioning research : the research journal of the NSCA},
  number    = {6},
  publisher = {Lippincott Williams \& Wilkins},
  address   = {Philadelphia},
  issn      = {1064-8011},
  doi       = {10.1519/JSC.0000000000002950},
  pages     = {1642 -- 1649},
  year      = {2021},
  abstract  = {This study examined the effect of 6 weeks of progressed and nonprogressed volume-based overload plyometric training (PT) on components of physical fitness and body composition measures in young male basketball players, compared with an active control group. Subjects were randomly assigned to a progressed PT (PPT, n = 7; age = 14.6 +/- 1.1 years), a non-PPT (NPPT, n = 8, age = 13.8 +/- 2.0 years), or a control group (CG, n = 7, age = 14.0 +/- 2.0 years). Before and after training, body composition measures (muscle mass and fat mass), countermovement jump with arms (CMJA) and countermovement jump without arms (CMJ), horizontal bilateral (HCMJ) and unilateral jump with right leg (RJ) and left leg (LJ), 20-cm drop jump (DJ20), sprint speed (10 m sprint), and change of direction speed (CODS [i.e., T-test]) were tested. Significant effects of time were observed for muscle and fat mass, all jump measures, and CODS (all p < 0.01; d = 0.37-0.83). Significant training group x time interactions were observed for all jump measures (all p < 0.05; d = 0.24-0.41). Post hoc analyses revealed significant pre-post performance improvements for the PPT (RJ and LJ: increment 18.6\%, d = 0.8 and increment 22.7\%, d = 0.9, respectively; HCMJ: increment 16.4\%, d = 0.8; CMJ: increment 22.4\%, d = 0.7; CMJA: increment 23.3\%, d = 0.7; and DJ20: increment 39.7\%, d = 1.1) and for the NPPT group (LJ: increment 14.1\%, d = 0.4; DJ20: increment 32.9\%, d = 0.8) with greater changes after PPT compared with NPPT for all jump measures (all p < 0.05; d = 0.21-0.81). The training efficiency was greater (p < 0.05; d = 0.22) after PPT (0.015\% per jump) compared with NPPT (0.0053\% per-jump). The PPT induced larger performance improvements on measures of physical fitness as compared to NPPT. Therefore, in-season progressive volume-based overload PT in young male basketball players is recommended.},
  language  = {en}
}
@article{SammoudNegraBouguezzietal.2021,
  author    = {Sammoud, Senda and Negra, Yassine and Bouguezzi, Raja and Hachana, Younes and Granacher, Urs and Chaabene, Helmi},
  title     = {The effects of plyometric jump training on jump and sport-specific performances in prepubertal female swimmers},
  series = {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},
  volume    = {19},
  journal   = {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},
  number    = {1},
  publisher = {Elsevier},
  address   = {Singapore},
  issn      = {1728-869x},
  doi       = {10.1016/j.jesf.2020.07.003},
  pages     = {25 -- 31},
  year      = {2021},
  abstract  = {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.},
  language  = {en}
}
@article{HammamiChaabeneKharratetal.2021,
  author    = {Hammami, Raouf and Chaabene, Helmi and Kharrat, Fatma and Werfelli, Hanen and Duncan, Michael and Rebai, Haithem and Granacher, Urs},
  title     = {Acute effects of different balance exercise types on selected measures of physical fitness in youth female volleyball players},
  series = {BMC Sports Science, Medicine and Rehabilitation},
  volume    = {13},
  journal   = {BMC Sports Science, Medicine and Rehabilitation},
  publisher = {BioMed Central},
  address   = {London},
  issn      = {1758-2555},
  doi       = {10.1186/s13102-021-00249-5},
  pages     = {8},
  year      = {2021},
  abstract  = {Background Earlier studies have shown that balance training (BT) has the potential to induce performance enhancements in selected components of physical fitness (i.e., balance, muscle strength, power, speed). While there is ample evidence on the long-term effects of BT on components of physical fitness in youth, less is known on the short-term or acute effects of single BT sessions on selected measures of physical fitness. Objective To examine the acute effects of different balance exercise types on balance, change-of-direction (CoD) speed, and jump performance in youth female volleyball players. Methods Eleven female players aged 14 years participated in this study. Three types of balance exercises (i.e., anterior, posterolateral, rotational type) were conducted in randomized order. For each exercise, 3 sets including 5 repetitions were performed. Before and after the performance of the balance exercises, participants were tested for their static balance (center of pressure surface area [CoP SA] and velocity [CoP V]) on foam and firm surfaces, CoD speed (T-Half test), and vertical jump height (countermovement jump [CMJ] height). A 3 (condition: anterior, mediolateral, rotational balance exercise type) × 2 (time: pre, post) analysis of variance was computed with repeated measures on time. Results Findings showed no significant condition × time interactions for all outcome measures (p > 0.05). However, there were small main effects of time for CoP SA on firm and foam surfaces (both d = 0.38; all p < 0.05) with no effect for CoP V on both surface conditions (p > 0.05). For CoD speed, findings showed a large main effect of time (d = 0.91; p < 0.001). However, for CMJ height, no main effect of time was observed (p > 0.05). Conclusions Overall, our results indicated small-to-large changes in balance and CoD speed performances but not in CMJ height in youth female volleyball players, regardless of the balance exercise type. Accordingly, it is recommended to regularly integrate balance exercises before the performance of sport-specific training to optimize performance development in youth female volleyball players.},
  language  = {en}
}
@article{BrahmsHortobagyiKressigetal.2021,
  author    = {Brahms, Clemens Markus and Hortob{\´a}gyi, Tibor and Kressig, Reto W. and Granacher, Urs},
  title     = {The Interaction between mobility status and exercise specificity in older adults},
  series = {Exercise and sport sciences reviews},
  volume    = {49},
  journal   = {Exercise and sport sciences reviews},
  number    = {1},
  publisher = {Lippincott Williams \& Wilkins},
  address   = {Hagerstown, Md.},
  issn      = {0091-6331},
  doi       = {10.1249/JES.0000000000000237},
  pages     = {15 -- 22},
  year      = {2021},
  abstract  = {Many adults older than 60 yr experience mobility limitations. Although physical exercise improves older adults' mobility, differences in baseline mobility produce large variations in individual responses to interventions, and these responses could further vary by the type and dose of exercise. Here, we propose an exercise prescription model for older adults based on their current mobility status.},
  language  = {en}
}
@article{JafarnezhadgeroGhorbanlooFatollahietal.2021,
  author    = {Jafarnezhadgero, AmirAli and Ghorbanloo, Farshad and Fatollahi, Amir and Dionisio, Valdeci Carlos and Granacher, Urs},
  title     = {Effects of an elastic resistance band exercise program on kinetics and muscle activities during walking in young adults with genu valgus},
  series = {Clinical biomechanics : a journal affiliated to the International Society of Biomechanics and the American Society of Biomechanics},
  volume    = {81},
  journal   = {Clinical biomechanics : a journal affiliated to the International Society of Biomechanics and the American Society of Biomechanics},
  publisher = {Elsevier Science},
  address   = {Amsterdam [u.a.]},
  issn      = {0268-0033},
  doi       = {10.1016/j.clinbiomech.2020.105215},
  pages     = {10},
  year      = {2021},
  abstract  = {Background: This double-blinded randomized-controlled-trial aimed to identify the effects of an elastic band resistance training on walking kinetics and muscle activities in young adults with genu valgus. Methods: Forty-two male young adults aged 22.5(2.7) years with genu valgus were randomly allocated to two experimental groups. The intervention group (n = 21) conducted a 14-weeks elastic band resistance training. The control group was passive during the intervention period and received the same treatment after the post-tests. Pre and post training, ground reaction forces and lower limb muscle activities were recorded during walking. Findings: Results revealed significant group-by-time interactions for peak medial ground reaction force and timeto-peak for posterior ground reaction force in favor of the intervention group (p < 0.012; d = 0.83-3.76). Resistance training with elastic bands resulted in significantly larger peak medial ground reaction force (p < 0.001; d = 1.45) and longer time-to-peak for posterior ground reaction force (p < 0.001; d = 1.85). Finding showed significant group-by-time interactions for peak positive free moment amplitudes in favor of the intervention group (p < 0.001; d = 1.18-2.02). Resistance training resulted in a lower peak positive free moment amplitude (p = 0.001; d = 1.46). With regards to muscle activities, the analysis revealed significant group-by time interactions for rectus femoris and gluteus medius activities during the push-off phase in favor of the intervention group (p < 0.038; d = 0.68-0.89). Resistance training induced higher rectus femoris (p = 0.038; d = 0.84) and gluteus medius (p = 0.007; d = 0.54) activities. Interpretation: This study proved the effectiveness of resistance training using elastic bands on kinetics and muscle activities during walking in male adults with genu valgus disorder. Given that this training regime is low cost, effective, and easy-to-administer, we suggest that it should be implemented as a rehabilitative or preventive means for young adults with genu valgus.},
  language  = {en}
}
@article{WickKriemlerGranacher2021,
  author    = {Wick, Kristin and Kriemler, Susi and Granacher, Urs},
  title     = {Effects of a strength-dominated exercise program on physical fitness and cognitive performance in preschool children},
  series = {Journal of strength and conditioning research : the research journal of the NSCA},
  volume    = {35},
  journal   = {Journal of strength and conditioning research : the research journal of the NSCA},
  number    = {4},
  publisher = {Lippincott Williams \& Wilkins},
  address   = {Philadelphia},
  issn      = {1064-8011},
  doi       = {10.1519/JSC.0000000000003942},
  pages     = {983 -- 990},
  year      = {2021},
  abstract  = {Wick, K, Kriemler, S, and Granacher, U. Effects of a strength-dominated exercise program on physical fitness and cognitive performance in preschool children. J Strength Cond Res 35(4): 983-990, 2021-Childhood is characterized by high neuroplasticity that affords qualitative rather than quantitative components of physical activity to maximize the potential to sufficiently develop motor skills and foster long-term engagement in regular physical activity. This study examined the effects of an integrative strength-dominated exercise program on measures of physical fitness and cognitive performance in preschool children. Children aged 4-6 years from 3 kindergartens were randomized into an intervention (INT) group (n = 32) or a control group (n = 22). The 10-week intervention period was conducted 3 times per week (each session lasted 30 minutes) and included exercises for the promotion of muscle strength and power, coordination, and balance. Pre and post training, tests were conducted for the assessment of muscle strength (i.e., handgrip strength), muscle power (i.e., standing long jump), balance (i.e., timed single-leg stand), coordination (hopping on right/left leg), and attentional span (i.e., "Konzentrations-Handlungsverfahren fur Vorschulkinder" [concentration-action procedure for preschoolers]). Results from 2 x 2 repeated-measures analysis of covariance revealed a significant (p <= 0.05) and near significant (p = 0.051) group x time interaction for the standing long jump test and the Konzentrations-Handlungsverfahren. Post hoc tests showed significant pre-post changes for the INT (p < 0.001; d = 1.53) but not the CON (p = 0.72; d = 0.83). Our results indicate that a 10-week strength-dominated exercise program increased jump performance with a concomitant trend toward improvements in attentional capacity of preschool children. Thus, we recommend implementing this type of exercise program for preschoolers.},
  language  = {en}
}
@article{HortobagyiDeakFarkasetal.2021,
  author    = {Hortobagyi, Tibor and Deak, Dorina and Farkas, Dora and Blenyesi, Eszter and Torok, Katalin and Granacher, Urs and Tollar, Jozsef},
  title     = {Effects of exercise dose and detraining duration on mobility at late midlife},
  series = {Gerontology},
  volume    = {67},
  journal   = {Gerontology},
  number    = {4},
  publisher = {Karger},
  address   = {Basel},
  issn      = {0304-324X},
  doi       = {10.1159/000513505},
  pages     = {403 -- 414},
  year      = {2021},
  abstract  = {Background: Office workers near retirement tend to be sedentary and can be prone to mobility limitations and diseases. We examined the dose effects of exergaming volume and duration of detraining on motor and cognitive function in office workers at late midlife to reduce sedentariness and mobility limitations. Methods: In an assessor-blinded randomized trial, 160 workers aged 55-65 years performed physically active video games in a nonimmersive form of virtual reality (exergaming) in small, supervised groups for 1 h, 1x, 2x, or 3x/week for 8 weeks followed by detraining for 8 and 16 weeks. Exergaming comprises high-intensity, full-body sensorimotor coordination, balance, endurance, and strengthening exercises. The primary outcome was the 6-minute walk test (6MWT), and secondary outcomes were body mass, self-reported physical activity, sleep quality, Berg Balance Scale, Short Physical Performance Battery, fast gait speed, dynamic balance, heart rate recovery after step test, and 6 cognitive tests. Results: The 3 groups were not different in any of the outcomes at baseline (all p > 0.05). The outcomes were stable and had acceptable reliability (intraclass correlation coefficients >= 0.334) over an 8-week control period. Training produced an inverted U-shaped dose response of no (1x), most (2x), and medium (3x/week) effects of exergaming volume in most motor and selected cognitive outcomes. The distance walked in the 6MWT (primary outcome) increased most (94 m, 19\%, p < 0.05), medium (57 m, 12\%, p < 0.05), and least (4 m, 1\%) after exergaming 2x, 3x, or 0x (control) (all different p < 0.05). The highest responders tended to retain the exercise effects over 8 weeks of detraining, independent of training volume. This maintenance effect was less consistent after 16 weeks of detraining. Conclusion: Less was more during training and lasted longer after detraining. A medium dose volume of exergaming produced the largest clinically meaningful improvements in mobility and selected cognitive tests in 60-year-old office workers with mild mobility limitations and intact cognition.},
  language  = {en}
}
@article{LesinskiPrieskeChaabeneetal.2021,
  author    = {Lesinski, Melanie and Prieske, Olaf and Chaabene, Helmi and Granacher, Urs},
  title     = {Seasonal effects of strength endurance vs. power training in young female soccer athletes},
  series = {Journal of strength and conditioning research : the research journal of the NSCA},
  volume    = {35},
  journal   = {Journal of strength and conditioning research : the research journal of the NSCA},
  number    = {Supplement 12},
  publisher = {Lippincott Williams \& Wilkins},
  address   = {Philadelphia},
  issn      = {1064-8011},
  doi       = {10.1519/JSC.0000000000003564},
  pages     = {S90 -- S96},
  year      = {2021},
  abstract  = {Lesinski, M, Prieske, O, Chaabene, H, and Granacher, U. Seasonal effects of strength endurance vs. power training in young female soccer athletes. J Strength Cond Res 35(12S): S90-S96, 2021-This study examined the seasonal effects of strength endurance training (SET) vs. power training (PT) on physical fitness and body composition in young female soccer players. Thirty-six young female elite soccer players (15 +/- 1 years; maturity offset +3 +/- 1 years) were allocated to progressive SET (n = 19) or PT (n = 17). Over the course of one soccer season, SET performed slow movement velocity, moderate intensity (50-60\% of the 1 repetition maximum [1RM]; 20-40 repetitions) strength exercises while PT performed moderate-to-high intensity (50-95\% of the 1RM; 3-8 repetitions), high movement velocity strength exercises (2 sessions center dot wk(-1)). Before and after training, tests were performed for the assessment of muscle strength (1RM leg press), jump performance (countermovement jump [CMJ], drop jump [DJ]), muscular endurance (ventral Bourban test), linear speed (10 m, 20 m), change-of-direction (CoD) speed (T-test), dynamic balance (Y-balance test), sport-specific performance (kicking velocity), and body composition (lean body mass and fat mass). An analysis of covariance was used to test for between-group differences at post-test with baseline values as covariate. No significant between-group differences were observed in terms of total training volume over the respective soccer seasons (p = 0.069; d = 0.68). At post-test, SET showed significantly better ventral Bourban and T-test performances (d = 1.28-2.28; p = 0.000-0.001) compared with PT. However, PT resulted in significantly better 1RM leg press, DJ, 10-m, and 20-m sprint performances (d = 0.85-1.44; p = 0.000-0.026). No significant between-group differences were observed at post-test for CMJ, Y-balance test, kicking performance, and body composition (d = 0.20-0.74, p = 0.051-0.594). Our findings are mainly in accordance with the principle of training specificity. Both SET and PT are recommended to be implemented in young female elite soccer players according to the respective training period.},
  language  = {en}
}
@article{DaviesDruryRamirezCampilloetal.2021,
  author    = {Davies, Michael J. and Drury, Benjamin and Ramirez-Campillo, Rodrigo and Chaabene, Helmi and Moran, Jason},
  title     = {Effect of plyometric training and biological maturation on jump and change of direction ability in female youth},
  series = {Journal of strength and conditioning research : the research journal of the NSCA / National Strength \& Conditioning Association},
  volume    = {35},
  journal   = {Journal of strength and conditioning research : the research journal of the NSCA / National Strength \& Conditioning Association},
  number    = {10},
  publisher = {Lippincott Williams \& Wilkins},
  address   = {Philadelphia},
  issn      = {1064-8011},
  doi       = {10.1519/JSC.0000000000003216},
  pages     = {2690 -- 2697},
  year      = {2021},
  abstract  = {Biological maturation has been shown to affect male youths' responses to plyometric training (PT). However, to date, no researcher has examined the effect of maturation on the effects of PT in female youth. We undertook the first controlled intervention study to examine this, focusing on adaptive responses to countermovement jump (CMJ), reactive strength index (RSI), and change of direction (COD) performance in groups of female youth divided by maturation status (years from peak height velocity [PHV]). The training program lasted 7 weeks with subjects undertaking 2 sessions of PT per week. In the mid-PHV group, there was a small increase (effect size; 90\% confidence interval = 0.40; -0.23 to 1.03) in CMJ performance. No changes were observed in the post-PHV group (0.02; -0.68 to 0.72). For RSI, there was a moderate increase in the mid-PHV group (0.94; 0.29-1.59) with only a trivial increase in the post-PHV group (0.06; -0.65 to 0.76). The intervention exerted no positive effect on COD performance in any group. Plyometric training seems to enhance CMJ and RSI in female youth, although the magnitude of adaptation could be affected by maturation status. A twice-per-week program of multidirectional jumping and hopping, with bilateral and unilateral components, can be used as a preparatory precursor to physical education classes or recreational sport.},
  language  = {en}
}