@article{ThielePrieskeChaabeneetal.2020,
  author    = {Thiele, Dirk and Prieske, Olaf and Chaabene, Helmi and Granacher, Urs},
  title     = {Effects of strength training on physical fitness and sport-specific performance in recreational, sub-elite, and elite rowers},
  series = {Journal of sports sciences},
  volume    = {38},
  journal   = {Journal of sports sciences},
  number    = {10},
  publisher = {Routledge, Taylor \& Francis Group},
  address   = {Abingdon},
  issn      = {0264-0414},
  doi       = {10.1080/02640414.2020.1745502},
  pages     = {1186 -- 1195},
  year      = {2020},
  abstract  = {The purpose of this systematic review with meta-analysis was to examine the effects of strength training (ST) on selected components of physical fitness (e.g., lower/upper limb maximal strength, muscular endurance, jump performance, cardiorespiratory endurance) and sport-specific performance in rowers. Only studies with an active control group were included if they examined the effects of ST on at least one proxy of physical fitness and/or sport-specific performance in rowers. Weighted and averaged standardized mean differences (SMD) were calculated using random-effects models. Subgroup analyses were computed to identify effects of ST type or expertise level on sport-specific performance. Our analyses revealed significant small effects of ST on lower limb maximal strength (SMD = 0.42, p = 0.05) and on sport-specific performance (SMD = 0.32, p = 0.05). Non-significant effects were found for upper limb maximal strength, upper/lower limb muscular endurance, jump performance, and cardiorespiratory endurance. Subgroup analyses for ST type and expertise level showed non-significant differences between the respective subgroups of rowers (p >= 0.32). Our systematic review with meta-analysis indicated that ST is an effective means for improving lower limb maximal strength and sport-specific performance in rowers. However, ST-induced effects are neither modulated by ST type nor rowers' expertise level.},
  language  = {en}
}
@article{SchinkoethBrand2020,
  author    = {Schink{\"o}th, Michaela and Brand, Ralf},
  title     = {Automatic associations and the affective valuation of exercise},
  series = {German Journal of Exercise and Sport Research},
  volume    = {50},
  journal   = {German Journal of Exercise and Sport Research},
  number    = {654},
  publisher = {Springer},
  address   = {Berlin ; Heidelberg},
  issn      = {2509-3150},
  doi       = {10.1007/s12662-020-00664-9},
  pages     = {366 -- 376},
  year      = {2020},
  abstract  = {The decision to exercise is not only bound to rational considerations but also automatic affective processes. The affective-reflective theory of physical inactivity and exercise (ART) proposes a theoretical framework for explaining how the automatic affective process (type‑1 process) will influence exercise behavior, i.e., through the automatic activation of exercise-related associations and a subsequent affective valuation of exercise. This study aimed to empirically test this assumption of the ART with data from 69 study participants. A single-measurement study, including within-subject experimental variation, was conducted. Automatic associations with exercise were first measured with a single-target implicit association test. The somato-affective core of the participants' automatic valuation of exercise-related pictures was then assessed via heart rate variability (HRV) analysis, and the affective valence of the valuation was tested with a facial expression (FE; smile and frown) task. Exercise behavior was assessed via self-report. Multiple regression (path) analysis revealed that automatic associations predicted HRV reactivity (β = -0.24, p = .044); the signs of the correlation between automatic associations and the smile FE score was in the expected direction but remained nonsignificant (β = -0.21, p = .078). HRV reactivity predicted self-reported exercise behavior (β = -0.28, p = .013) (the same pattern of results was achieved for the frown FE score). The HRV-related results illustrate the potential role of automatic negative affective reactions to the thought of exercise as a restraining force in exercise motivation. For better empirical distinction between the two ART type‑1 process components, automatic associations and the affective valuation should perhaps be measured separately in the future. The results support the notion that automatic and affective processes should be regarded as essential aspects of the motivation to exercise.},
  language  = {en}
}
@misc{SchinkoethBrand2020,
  author    = {Schink{\"o}th, Michaela and Brand, Ralf},
  title     = {Automatic associations and the affective valuation of exercise},
  series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-47552},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-475522},
  pages     = {366 -- 376},
  year      = {2020},
  abstract  = {The decision to exercise is not only bound to rational considerations but also automatic affective processes. The affective-reflective theory of physical inactivity and exercise (ART) proposes a theoretical framework for explaining how the automatic affective process (type‑1 process) will influence exercise behavior, i.e., through the automatic activation of exercise-related associations and a subsequent affective valuation of exercise. This study aimed to empirically test this assumption of the ART with data from 69 study participants. A single-measurement study, including within-subject experimental variation, was conducted. Automatic associations with exercise were first measured with a single-target implicit association test. The somato-affective core of the participants' automatic valuation of exercise-related pictures was then assessed via heart rate variability (HRV) analysis, and the affective valence of the valuation was tested with a facial expression (FE; smile and frown) task. Exercise behavior was assessed via self-report. Multiple regression (path) analysis revealed that automatic associations predicted HRV reactivity (β = -0.24, p = .044); the signs of the correlation between automatic associations and the smile FE score was in the expected direction but remained nonsignificant (β = -0.21, p = .078). HRV reactivity predicted self-reported exercise behavior (β = -0.28, p = .013) (the same pattern of results was achieved for the frown FE score). The HRV-related results illustrate the potential role of automatic negative affective reactions to the thought of exercise as a restraining force in exercise motivation. For better empirical distinction between the two ART type‑1 process components, automatic associations and the affective valuation should perhaps be measured separately in the future. The results support the notion that automatic and affective processes should be regarded as essential aspects of the motivation to exercise.},
  language  = {en}
}
@misc{SandauGranacher2020,
  author    = {Sandau, Ingo and Granacher, Urs},
  title     = {Effects of the barbell load on the acceleration phase during the snatch in Olympic weightlifting},
  series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {681},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-47159},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-471599},
  pages     = {12},
  year      = {2020},
  abstract  = {The load-depended loss of vertical barbell velocity at the end of the acceleration phase limits the maximum weight that can be lifted. Thus, the purpose of this study was to analyze how increased barbell loads affect the vertical barbell velocity in the sub-phases of the acceleration phase during the snatch. It was hypothesized that the load-dependent velocity loss at the end of the acceleration phase is primarily associated with a velocity loss during the 1st pull. For this purpose, 14 male elite weightlifters lifted seven load-stages from 70-100\% of their personal best in the snatch. The load-velocity relationship was calculated using linear regression analysis to determine the velocity loss at 1st pull, transition, and 2nd pull. A group mean data contrast analysis revealed the highest load-dependent velocity loss for the 1st pull (t = 1.85, p = 0.044, g = 0.49 [-0.05, 1.04]) which confirmed our study hypothesis. In contrast to the group mean data, the individual athlete showed a unique response to increased loads during the acceleration sub-phases of the snatch. With the proposed method, individualized training recommendations on exercise selection and loading schemes can be derived to specifically improve the sub-phases of the snatch acceleration phase. Furthermore, the results highlight the importance of single-subject assessment when working with elite athletes in Olympic weightlifting.},
  language  = {en}
}
@article{SandauGranacher2020,
  author    = {Sandau, Ingo and Granacher, Urs},
  title     = {Effects of the barbell load on the acceleration phase during the snatch in elite Olympic weightlifting},
  series = {Sports},
  volume    = {8},
  journal   = {Sports},
  number    = {5},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2075-4663},
  doi       = {10.3390/sports8050059},
  pages     = {10},
  year      = {2020},
  abstract  = {The load-depended loss of vertical barbell velocity at the end of the acceleration phase limits the maximum weight that can be lifted. Thus, the purpose of this study was to analyze how increased barbell loads affect the vertical barbell velocity in the sub-phases of the acceleration phase during the snatch. It was hypothesized that the load-dependent velocity loss at the end of the acceleration phase is primarily associated with a velocity loss during the 1st pull. For this purpose, 14 male elite weightlifters lifted seven load-stages from 70-100\% of their personal best in the snatch. The load-velocity relationship was calculated using linear regression analysis to determine the velocity loss at 1st pull, transition, and 2nd pull. A group mean data contrast analysis revealed the highest load-dependent velocity loss for the 1st pull (t = 1.85, p = 0.044, g = 0.49 [-0.05, 1.04]) which confirmed our study hypothesis. In contrast to the group mean data, the individual athlete showed a unique response to increased loads during the acceleration sub-phases of the snatch. With the proposed method, individualized training recommendations on exercise selection and loading schemes can be derived to specifically improve the sub-phases of the snatch acceleration phase. Furthermore, the results highlight the importance of single-subject assessment when working with elite athletes in Olympic weightlifting.},
  language  = {en}
}
@misc{SammoudNegraBouguezzietal.2020,
  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 = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {658},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-47827},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-478272},
  pages     = {9},
  year      = {2020},
  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{SallenAndraeLudygaetal.2020,
  author    = {Sallen, Jeffrey and Andr{\"a}, Christian and Ludyga, Sebastian and M{\"u}cke, Manuel and Herrmann, Christian},
  title     = {School children's physical activity, motor competence, and corresponding self-perception},
  series = {Journal of physical activity and health},
  volume    = {17},
  journal   = {Journal of physical activity and health},
  number    = {11},
  publisher = {Human Kinetics Publ.},
  address   = {Champaign},
  issn      = {1543-3080},
  doi       = {10.1123/jpah.2019-0507},
  pages     = {1083 -- 1090},
  year      = {2020},
  abstract  = {Background: The relationship between engagement in physical activity and the development of motor competence (MC) is considered to be reciprocal and dynamic throughout childhood and adolescence. The 10-month follow-up study aimed to explore this reciprocal relationship and investigated whether the relationship is mediated by the corresponding self-perception of MC (PMC). Methods: A total of 51 children aged between 10 and 11 years (M = 10.27 [0.45]) participated in the study (52.9\% boys, 47.1\% girls). As an indicator for physical activity, the average vigorous physical activity (VPA) per day was measured by ActiGraph accelerometers. Two aspects of MC and PMC were recorded: self-movement and object movement. Saturated pathway models in a cross-lagged panel design with 2 measurement points were analyzed. Results: Reciprocal and direct relationships between VPA and MC object movement respectively MC self-movement were not found in longitudinal analyses with PMC as a mediator. Indirect effects of MC at t1 on VPA at t2 via PMC were identified (self-movement: beta = 0.13, 95\% confidence interval, 0.04 to 0.26; object movement: beta = 0.14, 95\% confidence interval, 0.01 to 0.49). Conclusion: The results highlight the importance of MC and PMC in promoting children's VPA. However, VPA does not drive the development of MC.},
  language  = {en}
}
@misc{PavillonTournyBenAbderrahmanetal.2020,
  author    = {Pavillon, Thomas and Tourny, Claire and Ben Abderrahman, Abderraouf and Salhi, Iyed and Zouita, Sghaeir and Rouissi, Mehdi and Hackney, Anthony C. and Granacher, Urs and Zouhal, Hassane},
  title     = {Sprint and jump performances in highly trained young soccer players of different chronological age},
  series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {697},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-49055},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-490557},
  pages     = {12},
  year      = {2020},
  abstract  = {Objective The aim of this study was to examine the effects of two different sprint-training regimes on sprint and jump performances according to age in elite young male soccer players over the course of one soccer season. Methods Players were randomly assigned to two training groups. Group 1 performed systematic change-of-direction sprints (CODST, U19 [n = 9], U17 [n = 9], U15 [n = 10]) while group 2 conducted systematic linear sprints (LST, U19 [n = 9], U17 [n = 9], U15 [n = 9]). Training volumes were similar between groups (40 sprints per week x 30 weeks = 1200 sprints per season). Pre and post training, all players performed tests for the assessment of linear and slalom sprint speed (5-m and 10-m), countermovement jump, and maximal aerobic speed performance. Results For all physical fitness measures, the baseline-adjusted means data (ANCOVA) across the age groups showed no significant differences between LST and CODST at post (0.061 < p < 0.995; 0.0017 < d < 1.01). The analyses of baseline-adjusted means for all physical fitness measures for U15, U17, and U19 (LST vs. CODST) revealed no significant differences between LST and CODST for U15 (0.213 < p < 0.917; 0.001 < d < 0.087), U17 (0.132 < p < 0.976; 0.001 < d < 0.310), and U19 (0.300 < p < 0.999; 0.001 < d < 0.049) at post. Conclusions The results from this study showed that both, LST and CODST induced significant changes in the sprint, lower limbs power, and aerobic performances in young elite soccer players. Since no significant differences were observed between LST and CODST, the observed changes are most likely due to training and/or maturation. Therefore, more research is needed to elucidate whether CODST, LST or a combination of both is beneficial for youth soccer athletes' performance development.},
  language  = {en}
}
@article{PavillonTournyBenAbderrahmanetal.2020,
  author    = {Pavillon, Thomas and Tourny, Claire and Ben Abderrahman, Abderraouf and Salhi, Iyed and Zouita, Sghaeir and Rouissi, Mehdi and Hackney, Anthony C. and Granacher, Urs and Zouhal, Hassane},
  title     = {Sprint and jump performances in highly trained young soccer players of different chronological age},
  series = {Journal of Exercise Science \& Fitness},
  volume    = {19},
  journal   = {Journal of Exercise Science \& Fitness},
  number    = {2},
  publisher = {Elsevier},
  address   = {Singapore},
  issn      = {1728-869x},
  doi       = {10.1016/j.jesf.2020.10.003},
  pages     = {81 -- 90},
  year      = {2020},
  abstract  = {Objective The aim of this study was to examine the effects of two different sprint-training regimes on sprint and jump performances according to age in elite young male soccer players over the course of one soccer season. Methods Players were randomly assigned to two training groups. Group 1 performed systematic change-of-direction sprints (CODST, U19 [n = 9], U17 [n = 9], U15 [n = 10]) while group 2 conducted systematic linear sprints (LST, U19 [n = 9], U17 [n = 9], U15 [n = 9]). Training volumes were similar between groups (40 sprints per week x 30 weeks = 1200 sprints per season). Pre and post training, all players performed tests for the assessment of linear and slalom sprint speed (5-m and 10-m), countermovement jump, and maximal aerobic speed performance. Results For all physical fitness measures, the baseline-adjusted means data (ANCOVA) across the age groups showed no significant differences between LST and CODST at post (0.061 < p < 0.995; 0.0017 < d < 1.01). The analyses of baseline-adjusted means for all physical fitness measures for U15, U17, and U19 (LST vs. CODST) revealed no significant differences between LST and CODST for U15 (0.213 < p < 0.917; 0.001 < d < 0.087), U17 (0.132 < p < 0.976; 0.001 < d < 0.310), and U19 (0.300 < p < 0.999; 0.001 < d < 0.049) at post. Conclusions The results from this study showed that both, LST and CODST induced significant changes in the sprint, lower limbs power, and aerobic performances in young elite soccer players. Since no significant differences were observed between LST and CODST, the observed changes are most likely due to training and/or maturation. Therefore, more research is needed to elucidate whether CODST, LST or a combination of both is beneficial for youth soccer athletes' performance development.},
  language  = {en}
}
@article{NegraChaabeneFernandezFernandezetal.2020,
  author    = {Negra, Yassine and Chaabene, Helmi and Fernandez-Fernandez, Jaime and Sammoud, Senda and Bouguezzi, Raja and Prieske, Olaf and Granacher, Urs},
  title     = {Short-term plyometric Jump training improves repeated-sprint ability in prepuberal male soccer players},
  series = {Journal of strength and conditioning research : the research journal of the NSCA},
  volume    = {34},
  journal   = {Journal of strength and conditioning research : the research journal of the NSCA},
  number    = {11},
  publisher = {Lippincott Williams \& Wilkins},
  address   = {Philadelphia},
  issn      = {1064-8011},
  doi       = {10.1519/JSC.0000000000002703},
  pages     = {3241 -- 3249},
  year      = {2020},
  abstract  = {This study examined the effects of a short-term (i.e., 8 weeks) combined horizontal and vertical plyometric jump training (PJT) program in combination with regular soccer-specific training as compared with soccer-specific training only on jump and change of direction (CoD) performances, speed, and repeated-sprint ability (RSA) in prepuberal male soccer players. Twenty-four players were recruited and randomly assigned to either a PJT group (PJT(G); n = 13; 12.7 +/- 0.2 years) or an active control group (CONG; n = 11; 12.7 +/- 0.2 years). The outcome measures included tests for the assessment of jump performance (drop jump from 20- to 40-cm height [DJ20 and DJ40] and 3-hop test [THT]), speed (20-m sprint), CoD (T-test), and RSA (20-m repeated shuttle sprint). Data were analyzed using magnitude-based inferences. Within-group analyses revealed large performance improvements in the T-test (d = -1.2), DJ20 (d = 3.7), DJ40 (d = 3.6), THT (d = 0.6), and the RSA(total) (d = -1.6) in the PJT(G). Between-group analyses showed greater performance improvements in the T-test (d = -2.9), 20-m sprint time (d = -2.0), DJ20 (d = 2.4), DJ40 (d = 2.0), THT (d = 1.9), RSA(best) (d = -1.9), and the RSA(total) (d = -1.9) in the PJT(G) compared with CONG. Eight weeks of an in-season PJT in addition to regular soccer-specific training induced larger increases in measures of physical fitness in prepuberal male soccer players compared with regular soccer-specific training only. More specifically, PJT was effective in improving RSA performance.},
  language  = {en}
}