@misc{GranacherHortobagyi2015,
  author    = {Granacher, Urs and Hortob{\´a}gyi, Tibor},
  title     = {Exercise to improve mobility in healthy aging},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {897},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-43241},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-432419},
  pages     = {4},
  year      = {2015},
  language  = {en}
}
@misc{CoppalleRaveBenAbderrahmanetal.2019,
  author    = {Coppalle, Sullivan and Rave, Guillaume and Ben Abderrahman, Abderraouf and Ali, Ajmol and Salhi, Iyed and Zouita, Sghaier and Zouita, Amira and Brughelli, Matt and Granacher, Urs and Zouhal, Hassane},
  title     = {Relationship of Pre-season Training Load With In-Season Biochemical Markers, Injuries and Performance in Professional Soccer Players},
  series = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe},
  number    = {564},
  doi       = {10.25932/publishup-43602},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-436025},
  pages     = {11},
  year      = {2019},
  abstract  = {There is controversy in the literature in regards of the link between training load and injury rate. Thus, the aims of this non-interventional study were to evaluate relationships between pre-season training load with biochemical markers, injury incidence and performance during the first month of the competitive period in professional soccer players.},
  language  = {en}
}
@misc{GaeblerPrieskeHortobagyietal.2018,
  author    = {G{\"a}bler, Martijn and Prieske, Olaf and Hortobagyi, Tibor and Granacher, Urs},
  title     = {The Effects of Concurrent Strength and Endurance Training on Physical Fitness and Athletic Performance in Youth},
  series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {471},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-417683},
  pages     = {13},
  year      = {2018},
  abstract  = {Combining training of muscle strength and cardiorespiratory fitness within a training cycle could increase athletic performance more than single-mode training. However, the physiological effects produced by each training modality could also interfere with each other, improving athletic performance less than single-mode training. Because anthropometric, physiological, and biomechanical differences between young and adult athletes can affect the responses to exercise training, young athletes might respond differently to concurrent training (CT) compared with adults. Thus, the aim of the present systematic review with meta-analysis was to determine the effects of concurrent strength and endurance training on selected physical fitness components and athletic performance in youth. A systematic literature search of PubMed and Web of Science identified 886 records. The studies included in the analyses examined children (girls age 6-11 years, boys age 6-13 years) or adolescents (girls age 12-18 years, boys age 14-18 years), compared CT with single-mode endurance (ET) or strength training (ST), and reported at least one strength/power—(e.g., jump height), endurance—(e.g., peak 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.},
  language  = {en}
}
@misc{SaidiBenAbderrahmanBoullosaetal.2020,
  author    = {Saidi, Karim and Ben Abderrahman, Abderraouf and Boullosa, Daniel and Dupont, Gr{\´e}gory and Hackney, Anthony C. and Bideau, Benoit and Pavillon, Thomas and Granacher, Urs and Zouhal, Hassane},
  title     = {The Interplay Between Plasma Hormonal Concentrations, Physical Fitness, Workload and Mood State Changes to Periods of Congested Match Play in Professional Soccer Players},
  series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {660},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-47925},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-479259},
  pages     = {16},
  year      = {2020},
  abstract  = {Background: The regular assessment of hormonal and mood state parameters in professional soccer are proposed as good indicators during periods of intense training and/or competition to avoid overtraining. Objective: The aim of this study was to analyze hormonal, psychological, workload and physical fitness parameters in elite soccer players in relation to changes in training and match exposure during a congested period of match play. Methods: Sixteen elite soccer players from a team playing in the first Tunisian soccer league were evaluated three times (T1, T2, and T3) over 12 weeks. The non-congested period of match play was from T1 to T2, when the players played 6 games over 6 weeks. The congested period was from T2 to T3, when the players played 10 games over 6 weeks. From T1 to T3, players performed the Yo-Yo intermittent recovery test level 1 (YYIR1), the repeated shuttle sprint ability test (RSSA), the countermovement jump test (CMJ), and the squat jump test (SJ). Plasma Cortisol (C), Testosterone (T), and the T/C ratio were analyzed at T1, T2, and T3. Players had their mood dimensions (tension, depression, anger, vigor, fatigue, confusion, and a Total Mood Disturbance) assessed through the Profile of Mood State questionnaire (POMS). Training session rating of perceived exertion (sRPE) was also recorded on a daily basis in order to quantify internal training load and elements of monotony and strain. Results: Significant performance declines (T1 < T2 < T3) were found for SJ performance (p = 0.04, effect size [ES] ES₁₋₂ = 0.15-0.06, ES₂₋₃ = 0.24) from T1 to T3. YYIR1 performance improved significantly from T1 to T2 and declined significantly from T2 to T3 (p = 0.001, ES₁₋₂ = 0.24, ES₂₋₃ = -2.54). Mean RSSA performance was significantly higher (p = 0.019, ES₁₋₂ = -0.47, ES₂₋₃ = 1.15) in T3 compared with T2 and T1. Best RSSA performance was significantly higher in T3 when compared with T2 and T1 (p = 0.006, ES₂₋₃ = 0.47, ES₁₋₂ = -0.56), but significantly lower in T2 when compared with to T1. T and T/C were significantly lower in T3 when compared with T2 and T1 (T: p = 0.03, ES₃₋₂ = -0.51, ES₃₋₁ = -0.51, T/C: p = 0.017, ES₃₋₂ = -1.1, ES₃₋₁ = -1.07). Significant decreases were found for the vigor scores in T3 when compared to T2 and T1 (p = 0.002, ES₁₋₂ = 0.31, ES₃₋₂ = -1.25). A significant increase was found in fatigue scores in T3 as compared to T1 and T2 (p = 0.002, ES₁₋₂ = 0.43, ES₂₋₃ = 0.81). A significant increase was found from T1 < T2 < T3 intension score (p = 0.002, ES₁₋₂ = 1.1, ES₂₋₃ = 0.2) and anger score (p = 0.03, ES₁₋₂ = 0.47, ES₂₋₃ = 0.33) over the study period. Total mood disturbance increased significantly (p = 0.02, ES₁₋₂ = 0.91, ES₂₋₃ = 1.1) from T1 to T3. Between T1-T2, significant relationships were observed between workload and changes in T (r = 0.66, p = 0.003), and T/C ratio (r = 0.62, p = 0.01). There were significant relationships between performance in RSSAbest and training load parameters (workload: r = 0.52, p = 0.03; monotony: r = 0.62, p = 0.01; strain: r = 0.62, p = 0.009). Between T2-T3, there was a significant relationship between Δ\% of total mood disturbance and Δ\% of YYIR1 (r = -0.54; p = 0.04), RSSAbest (r = 0.58, p = 0.01), SJ (r = -0,55, p = 0.01), T (r = 0.53; p = 0.03), and T/C (r = 0.5; p = 0.04). Conclusion: An intensive period of congested match play significantly compromised elite soccer players' physical and mental fitness. These changes were related to psychological but not hormonal parameters; even though significant alterations were detected for selected measures. Mood monitoring could be a simple and useful tool to determine the degree of preparedness for match play during a congested period in professional soccer.},
  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}
}
@misc{ZouhalBenAbderrahmanDupontetal.2019,
  author    = {Zouhal, Hassane and Ben Abderrahman, Abderraouf and Dupont, Gregory and Truptin, Pablo and Le Bris, R{\´e}gis and Le Postec, Erwan and Sghaeir, Zouita and Brughelli, Matt and Granacher, Urs and Bideau, Benoit},
  title     = {Effects of Neuromuscular Training on Agility Performance in Elite Soccer Players},
  series = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe},
  number    = {575},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-43735},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-437358},
  pages     = {9},
  year      = {2019},
  abstract  = {Background: Agility in general and change-of-direction speed (CoD) in particular represent important performance determinants in elite soccer. Objectives: The objectives of this study were to determine the effects of a 6-week neuromuscular training program on agility performance, and to determine differences in movement times between the slower and faster turning directions in elite soccer players. Materials and Methods: Twenty male elite soccer players from the Stade Rennais Football Club (Ligue 1, France) participated in this study. The players were randomly assigned to a neuromuscular training group (NTG, n = 10) or an active control (CG, n = 10) according to their playing position. NTG participated in a 6-week, twice per week neuromuscular training program that included CoD, plyometric and dynamic stability exercises. Neuromuscular training replaced the regular warm-up program. Each training session lasted 30 min. CG continued their regular training program. Training volume was similar between groups. Before and after the intervention, the two groups performed a reactive agility test that included 180° left and right body rotations followed by a 5-m linear sprint. The weak side was defined as the left/right turning direction that produced slower overall movement times (MT). Reaction time (RT) was assessed and defined as the time from the first appearance of a visual stimulus until the athlete's first movement. MT corresponded to the time from the first movement until the athlete reached the arrival gate (5 m distance). Results: No significant between-group baseline differences were observed for RT or MT. Significant group x time interactions were found for MT (p = 0.012, effect size = 0.332, small) for the slower and faster directions (p = 0.011, effect size = 0.627, moderate). Significant pre-to post improvements in MT were observed for NTG but not CG (p = 0.011, effect size = 0.877, moderate). For NTG, post hoc analyses revealed significant MT improvements for the slower (p = 0.012, effect size = 0.897, moderate) and faster directions (p = 0.017, effect size = 0.968, moderate). Conclusion: Our results illustrate that 6 weeks of neuromuscular training with two sessions per week included in the warm-up program, significantly enhanced agility performance in elite soccer players. Moreover, improvements were found on both sides during body rotations. Thus, practitioners are advised to focus their training programs on both turning directions.},
  language  = {en}
}
@misc{CoppalleRaveMoranetal.2021,
  author    = {Coppalle, Sullivan and Rav{\´e}, Guillaume and Moran, Jason and Salhi, Iyed and Ben Abderrahman, Abderraouf and Zouita, Sghaeir and Granacher, Urs and Zouhal, Hassane},
  title     = {Internal and External Training Load in Under-19 versus Professional Soccer Players during the In-Season Period},
  series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {694},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-48974},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-489745},
  pages     = {12},
  year      = {2021},
  abstract  = {This study aimed to compare the training load of a professional under-19 soccer team (U-19) to that of an elite adult team (EAT), from the same club, during the in-season period. Thirty-nine healthy soccer players were involved (EAT [n = 20]; U-19 [n = 19]) in the study which spanned four weeks. Training load (TL) was monitored as external TL, using a global positioning system (GPS), and internal TL, using a rating of perceived exertion (RPE). TL data were recorded after each training session. During soccer matches, players' RPEs were recorded. The internal TL was quantified daily by means of the session rating of perceived exertion (session-RPE) using Borg's 0-10 scale. For GPS data, the selected running speed intensities (over 0.5 s time intervals) were 12-15.9 km/h; 16-19.9 km/h; 20-24.9 km/h; >25 km/h (sprint). Distances covered between 16 and 19.9 km/h, > 20 km/h and >25 km/h were significantly higher in U-19 compared to EAT over the course of the study (p = 0.023, d = 0.243, small; p = 0.016, d = 0.298, small; and p = 0.001, d = 0.564, small, respectively). EAT players performed significantly fewer sprints per week compared to U-19 players (p = 0.002, d = 0.526, small). RPE was significantly higher in U-19 compared to EAT (p = 0.001, d = 0.188, trivial). The external and internal measures of TL were significantly higher in the U-19 group compared to the EAT soccer players. In conclusion, the results obtained show that the training load is greater in U19 compared to EAT.},
  language  = {en}
}
@misc{ChaabeneBehmNegraetal.2019,
  author    = {Chaabene, Helmi and Behm, David George and Negra, Yassine and Granacher, Urs},
  title     = {Acute Effects of Static Stretching on Muscle Strength and Power},
  series = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe},
  number    = {585},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-44003},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-440036},
  pages     = {8},
  year      = {2019},
  abstract  = {The effects of static stretching (StS) on subsequent strength and power activities has been one of the most debated topics in sport science literature over the past decades. The aim of this review is (1) to summarize previous and current findings on the acute effects of StS on muscle strength and power performances; (2) to update readers' knowledge related to previous caveats; and (3) to discuss the underlying physiological mechanisms of short-duration StS when performed as single-mode treatment or when integrated into a full warm-up routine. Over the last two decades, StS has been considered harmful to subsequent strength and power performances. Accordingly, it has been recommended not to apply StS before strength- and power-related activities. More recent evidence suggests that when performed as a single-mode treatment or when integrated within a full warm-up routine including aerobic activity, dynamic-stretching, and sport-specific activities, short-duration StS (≤60 s per muscle group) trivially impairs subsequent strength and power activities (∆1-2\%). Yet, longer StS durations (>60 s per muscle group) appear to induce substantial and practically relevant declines in strength and power performances (∆4.0-7.5\%). Moreover, recent evidence suggests that when included in a full warm-up routine, short-duration StS may even contribute to lower the risk of sustaining musculotendinous injuries especially with high-intensity activities (e.g., sprint running and change of direction speed). It seems that during short-duration StS, neuromuscular activation and musculotendinous stiffness appear not to be affected compared with long-duration StS. Among other factors, this could be due to an elevated muscle temperature induced by a dynamic warm-up program. More specifically, elevated muscle temperature leads to increased muscle fiber conduction-velocity and improved binding of contractile proteins (actin, myosin). Therefore, our previous understanding of harmful StS effects on subsequent strength and power activities has to be updated. In fact, short-duration StS should be included as an important warm-up component before the uptake of recreational sports activities due to its potential positive effect on flexibility and musculotendinous injury prevention. However, in high-performance athletes, short-duration StS has to be applied with caution due to its negligible but still prevalent negative effects on subsequent strength and power performances, which could have an impact on performance during competition.},
  language  = {en}
}
@misc{GranacherBorde2017,
  author    = {Granacher, Urs and Borde, Ron},
  title     = {Effects of Sport-Specific Training during the Early Stages of Long-Term Athlete Development on Physical Fitness, Body Composition, Cognitive, and Academic Performances},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-403760},
  pages     = {11},
  year      = {2017},
  abstract  = {Introduction: Several sports demand an early start into long-term athlete development (LTAD) because peak performances are achieved at a relatively young age (e.g., gymnastics). However, the challenging combination of high training volumes and academic demands may impede youth athletes' cognitive and academic performances. Thus, the aims of this study were to examine the effects of a 1-year sport-specific training and/or physical education on physical fitness, body composition, cognitive and academic performances in youth athletes and their non-athletic peers. Methods: Overall, 45 prepubertal fourth graders from a German elite sport school were enrolled in this study. Participating children were either youth athletes from an elite sports class (n = 20, age 9.5 ± 0.5 years) or age-matched peers from a regular class (n = 25, age 9.6 ± 0.6 years). Over the 1-year intervention period, the elite sports class conducted physical education and sport-specific training (i.e., gymnastics, swimming, soccer, bicycle motocross [BMX]) during school time while the regular class attended physical education only. Of note, BMX is a specialized form of cycling that is performed on motocross tracks and affords high technical skills. Before and after intervention, tests were performed for the assessment of physical fitness (speed [20-m sprint], agility [star agility run], muscle power [standing long jump], flexibility [stand-and-reach], endurance [6-min-run], balance [single-leg stance]), body composition (e.g., muscle mass), cognitive (d2-test) and academic performance (reading [ELFE 1-6], writing [HSP 4-5], calculating [DEMAT 4]). In addition, grades in German, English, Mathematics, and physical education were documented. Results: At baseline, youth athletes showed better physical fitness performances (p < 0.05; d = 0.70-2.16), less relative body fat mass, more relative skeletal muscle mass (p < 0.01; d = 1.62-1.84), and similar cognitive and academic achievements compared to their non-athletic peers. Athletes' training volume amounted to 620 min/week over the 1-year period while their peers performed 155 min/week. After the intervention, significant differences were found in 6 out of 7 physical fitness tests (p < 0.05; d = 0.75-1.40) and in the physical education grades (p < 0.01; d = 2.36) in favor of the elite sports class. No significant between-group differences were found after the intervention in measures of body composition (p > 0.05; d = 0.66-0.67), cognition and academics (p > 0.05; d = 0.40-0.64). Our findings revealed no significant between-group differences in growth rate (deltas of pre-post-changes in body height and leg length). Discussion: Our results revealed that a school-based 1-year sport-specific training in combination with physical education improved physical fitness but did not negatively affect cognitive and academic performances of youth athletes compared to their non-athletic peers. It is concluded that sport-specific training in combination with physical education promotes youth athletes' physical fitness development during LTAD and does not impede their cognitive and academic development.},
  language  = {en}
}
@misc{PrieskeKruegerAehleetal.2018,
  author    = {Prieske, Olaf and Kr{\"u}ger, Tom and Aehle, Markus and Bauer, Erik and Granacher, Urs},
  title     = {Effects of Resisted Sprint Training and Traditional Power Training on Sprint, Jump, and Balance Performance in Healthy Young Adults},
  series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {383},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-409645},
  pages     = {10},
  year      = {2018},
  abstract  = {Power training programs have proved to be effective in improving components of physical fitness such as speed. According to the concept of training specificity, it was postulated that exercises must attempt to closely mimic the demands of the respective activity. When transferring this idea to speed development, the purpose of the present study was to examine the effects of resisted sprint (RST) vs. traditional power training (TPT) on physical fitness in healthy young adults. Thirty-five healthy, physically active adults were randomly assigned to a RST (n = 10, 23 ± 3 years), a TPT (n = 9, 23 ± 3 years), or a passive control group (n = 16, 23 ± 2 years). RST and TPT exercised for 6 weeks with three training sessions/week each lasting 45-60 min. RST comprised frontal and lateral sprint exercises using an expander system with increasing levels of resistance that was attached to a treadmill (h/p/cosmos). TPT included ballistic strength training at 40\% of the one-repetition-maximum for the lower limbs (e.g., leg press, knee extensions). Before and after training, sprint (20-m sprint), change-of-direction speed (T-agility test), jump (drop, countermovement jump), and balance performances (Y balance test) were assessed. ANCOVA statistics revealed large main effects of group for 20-m sprint velocity and ground contact time (0.81 ≤ d ≤ 1.00). Post-hoc tests showed higher sprint velocity following RST and TPT (0.69 ≤ d ≤ 0.82) when compared to the control group, but no difference between RST and TPT. Pre-to-post changes amounted to 4.5\% for RST [90\%CI: (-1.1\%;10.1\%), d = 1.23] and 2.6\% for TPT [90\%CI: (0.4\%;4.8\%), d = 1.59]. Additionally, ground contact times during sprinting were shorter following RST and TPT (0.68 ≤ d ≤ 1.09) compared to the control group, but no difference between RST and TPT. Pre-to-post changes amounted to -6.3\% for RST [90\%CI: (-11.4\%;-1.1\%), d = 1.45) and -2.7\% for TPT [90\%CI: (-4.2\%;-1.2\%), d = 2.36]. Finally, effects for change-of-direction speed, jump, and balance performance varied from small-to-large. The present findings indicate that 6 weeks of RST and TPT produced similar effects on 20-m sprint performance compared with a passive control in healthy and physically active, young adults. However, no training-related effects were found for change-of-direction speed, jump and balance performance. We conclude that both training regimes can be applied for speed development.},
  language  = {en}
}
@misc{JafarnezhadgeroShadMajlesietal.2017,
  author    = {Jafarnezhadgero, Amir Ali and Shad, Morteza Madadi and Majlesi, Mahdi and Granacher, Urs},
  title     = {A comparison of running kinetics in children with and without genu varus},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-403326},
  pages     = {15},
  year      = {2017},
  abstract  = {Introduction Varus knee alignment has been identified as a risk factor for the progression of medial knee osteoarthritis. However, the underlying mechanisms have not been elucidated yet in children. Thus, the aims of the present study were to examine differences in ground reaction forces, loading rate, impulses, and free moment values during running in children with and without genu varus. Methods Thirty-six boys aged 9-14 volunteered to participate in this study. They were divided in two age-matched groups (genu varus versus healthy controls). Body weight adjusted three dimensional kinetic data (Fx, Fy, Fz) were collected during running at preferred speed using two Kistler force plates for the dominant and non-dominant limb. Results Individuals with knee genu varus produced significantly higher (p = .01; d = 1.09; 95\%) body weight adjusted ground reaction forces in the lateral direction (Fx) of the dominant limb compared to controls. On the non-dominant limb, genu varus patients showed significantly higher body weight adjusted ground reaction forces values in the lateral (p = .01; d = 1.08; 86\%) and medial (p < .001; d = 1.55; 102\%) directions (Fx). Further, genu varus patients demonstrated 55\% and 36\% greater body weight adjusted loading rates in the dominant (p < .001; d = 2.09) and non-dominant (p < .001; d = 1.02) leg, respectively. No significant between-group differences were observed for adjusted free moment values (p>.05). Discussion Higher mediolateral ground reaction forces and vertical loading rate amplitudes in boys with genu varus during running at preferred running speed may accelerate the development of progressive joint degeneration in terms of the age at knee osteoarthritis onset. Therefore, practitioners and therapists are advised to conduct balance and strength training programs to improve lower limb alignment and mediolateral control during dynamic movements.},
  language  = {en}
}
@misc{GolleGranacherHoffmannetal.2014,
  author    = {Golle, Kathleen and Granacher, Urs and Hoffmann, Martin and Wick, Ditmar and M{\"u}hlbauer, Thomas},
  title     = {Effect of living area and sports club participation on physical fitness in children},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-401418},
  pages     = {8},
  year      = {2014},
  abstract  = {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.},
  language  = {en}
}
@misc{RamirezCampilloGarciaPinillosGarciaRamosetal.2018,
  author    = {Ramirez-Campillo, Rodrigo and Garc{\´i}a-Pinillos, Felipe and Garc{\´i}a-Ramos, Amador and Yanci, Javier and Gentil, Paulo and Chaabene, Helmi and Granacher, Urs},
  title     = {Effects of Different Plyometric Training Frequencies on Components of Physical Fitness in Amateur Female Soccer Players},
  series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {474},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-419377},
  pages     = {11},
  year      = {2018},
  abstract  = {Plyometric jump training (PJT) is a frequently used and effective means to improve amateur and elite soccer players' physical fitness. However, it is unresolved how different PJT frequencies per week with equal overall training volume may affect training-induced adaptations. Therefore, the aim of this study was to compare the effects of an in-season 8 week PJT with one session vs. two sessions per week and equal training volume on components of physical fitness in amateur female soccer players. A single-blind randomized controlled trial was conducted. Participants (N = 23; age, 21.4 ± 3.2 years) were randomly assigned to a one session PJT per-week (PJT-1, n = 8), two sessions PJT per-week (PJT-2, n = 8) or an active control group (CON, n = 7). Before and after training, participants performed countermovement jumps (CMJ), drop-jumps from a 20-cm drop-height (DJ20), a maximal kicking velocity test (MKV), the 15-m linear sprint-time test, the Meylan test for the assessment of change of direction ability (CoDA), and the Yo-Yo intermittent recovery endurance test (Yo-YoIR1). Results revealed significant main effects of time for the CMJ, DJ20, MKV, 15-m sprint, CoDA, and the Yo-YoIR1 (all p < 0.001; d = 0.57-0.83). Significant group × time interactions were observed for the CMJ, DJ20, MKV, 15-m sprint, CoDA, and the Yo-YoIR1 (all p < 0.05; d = 0.36-0.51). Post-hoc analyses showed similar improvements for PJT-1 and PJT-2 groups in CMJ (Δ10.6\%, d = 0.37; and Δ10.1\%, d = 0.51, respectively), DJ20 (Δ12.9\%, d = 0.47; and Δ13.1\%, d = 0.54, respectively), MKV (Δ8.6\%, d = 0.52; and Δ9.1\%, d = 0.47, respectively), 15-m sprint (Δ8.3\%, d = 2.25; and Δ9.5\%, d = 2.67, respectively), CoDA (Δ7.5\%, d = 1.68; and Δ7.4\%, d = 1.16, respectively), and YoYoIR1 (Δ10.3\%, d = 0.22; and Δ9.9\%, d = 0.26, respectively). No significant pre-post changes were found for CON (all p > 0.05; Δ0.5-4.2\%, d = 0.03-0.2). In conclusion, higher PJT exposure in terms of session frequency has no extra effects on female soccer players' physical fitness development when jump volume is equated during a short-term (i.e., 8 weeks) training program. From this, it follows that one PJT session per week combined with regular soccer-specific training appears to be sufficient to induce physical fitness improvements in amateur female soccer players.},
  language  = {en}
}
@misc{ChaabeneNegraBouguezzietal.2018,
  author    = {Chaabene, Helmi and Negra, Yassine and Bouguezzi, Raja and Capranica, Laura and Franchini, Emerson and Prieske, Olaf and Hbacha, Hamdi and Granacher, Urs},
  title     = {Tests for the Assessment of Sport-Specific Performance in Olympic Combat Sports},
  series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {436},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-411959},
  pages     = {18},
  year      = {2018},
  abstract  = {The regular monitoring of physical fitness and sport-specific performance is important in elite sports to increase the likelihood of success in competition. This study aimed to systematically review and to critically appraise the methodological quality, validation data, and feasibility of the sport-specific performance assessment in Olympic combat sports like amateur boxing, fencing, judo, karate, taekwondo, and wrestling. A systematic search was conducted in the electronic databases PubMed, Google-Scholar, and Science-Direct up to October 2017. Studies in combat sports were included that reported validation data (e.g., reliability, validity, sensitivity) of sport-specific tests. Overall, 39 studies were eligible for inclusion in this review. The majority of studies (74\%) contained sample sizes <30 subjects. Nearly, 1/3 of the reviewed studies lacked a sufficient description (e.g., anthropometrics, age, expertise level) of the included participants. Seventy-two percent of studies did not sufficiently report inclusion/exclusion criteria of their participants. In 62\% of the included studies, the description and/or inclusion of a familiarization session (s) was either incomplete or not existent. Sixty-percent of studies did not report any details about the stability of testing conditions. Approximately half of the studies examined reliability measures of the included sport-specific tests (intraclass correlation coefficient [ICC] = 0.43-1.00). Content validity was addressed in all included studies, criterion validity (only the concurrent aspect of it) in approximately half of the studies with correlation coefficients ranging from r = -0.41 to 0.90. Construct validity was reported in 31\% of the included studies and predictive validity in only one. Test sensitivity was addressed in 13\% of the included studies. The majority of studies (64\%) ignored and/or provided incomplete information on test feasibility and methodological limitations of the sport-specific test. In 28\% of the included studies, insufficient information or a complete lack of information was provided in the respective field of the test application. Several methodological gaps exist in studies that used sport-specific performance tests in Olympic combat sports. Additional research should adopt more rigorous validation procedures in the application and description of sport-specific performance tests in Olympic combat sports.},
  language  = {en}
}
@misc{SlimaniParavlicGranacher2018,
  author    = {Slimani, Maamer and Paravlic, Armin and Granacher, Urs},
  title     = {A Meta-Analysis to Determine Strength Training Related Dose-Response Relationships for Lower-Limb Muscle Power Development in Young Athletes},
  series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {472},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-417738},
  pages     = {14},
  year      = {2018},
  abstract  = {It is well-documented that strength training (ST) improves measures of muscle strength in young athletes. Less is known on transfer effects of ST on proxies of muscle power and the underlying dose-response relationships. The objectives of this meta-analysis were to quantify the effects of ST on lower limb muscle power in young athletes and to provide dose-response relationships for ST modalities such as frequency, intensity, and volume. A systematic literature search of electronic databases identified 895 records. Studies were eligible for inclusion if (i) healthy trained children (girls aged 6-11 y, boys aged 6-13 y) or adolescents (girls aged 12-18 y, boys aged 14-18 y) were examined, (ii) ST was compared with an active control, and (iii) at least one proxy of muscle power [squat jump (SJ) and countermovement jump height (CMJ)] was reported. Weighted mean standardized mean differences (SMDwm) between subjects were calculated. Based on the findings from 15 statistically aggregated studies, ST produced significant but small effects on CMJ height (SMDwm = 0.65; 95\% CI 0.34-0.96) and moderate effects on SJ height (SMDwm = 0.80; 95\% CI 0.23-1.37). The sub-analyses revealed that the moderating variable expertise level (CMJ height: p = 0.06; SJ height: N/A) did not significantly influence ST-related effects on proxies of muscle power. "Age" and "sex" moderated ST effects on SJ (p = 0.005) and CMJ height (p = 0.03), respectively. With regard to the dose-response relationships, findings from the meta-regression showed that none of the included training modalities predicted ST effects on CMJ height. For SJ height, the meta-regression indicated that the training modality "training duration" significantly predicted the observed gains (p = 0.02), with longer training durations (>8 weeks) showing larger improvements. This meta-analysis clearly proved the general effectiveness of ST on lower-limb muscle power in young athletes, irrespective of the moderating variables. Dose-response analyses revealed that longer training durations (>8 weeks) are more effective to improve SJ height. No such training modalities were found for CMJ height. Thus, there appear to be other training modalities besides the ones that were included in our analyses that may have an effect on SJ and particularly CMJ height. ST monitoring through rating of perceived exertion, movement velocity or force-velocity profile could be promising monitoring tools for lower-limb muscle power development in young athletes.},
  language  = {en}
}
@misc{HammamiChaabeneKharratetal.,
  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 = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {713},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-51747},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-517477},
  pages     = {10},
  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}
}
@misc{BeurskensHaegerKliegletal.2016,
  author    = {Beurskens, Rainer and Haeger, Matthias and Kliegl, Reinhold and Roecker, Kai and Granacher, Urs},
  title     = {Postural Control in Dual-Task Situations},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-96638},
  pages     = {1 -- 15},
  year      = {2016},
  abstract  = {Postural control is important to cope with demands of everyday life. It has been shown that both attentional demand (i.e., cognitive processing) and fatigue affect postural control in young adults. However, their combined effect is still unresolved. Therefore, we investigated the effects of fatigue on single- (ST) and dual-task (DT) postural control. Twenty young subjects (age: 23.7 ± 2.7) performed an all-out incremental treadmill protocol. After each completed stage, one-legged-stance performance on a force platform under ST (i.e., one-legged-stance only) and DT conditions (i.e., one-legged-stance while subtracting serial 3s) was registered. On a second test day, subjects conducted the same balance tasks for the control condition (i.e., non-fatigued). Results showed that heart rate, lactate, and ventilation increased following fatigue (all p < 0.001; d = 4.2-21). Postural sway and sway velocity increased during DT compared to ST (all p < 0.001; d = 1.9-2.0) and fatigued compared to non-fatigued condition (all p < 0.001; d = 3.3-4.2). In addition, postural control deteriorated with each completed stage during the treadmill protocol (all p < 0.01; d = 1.9-3.3). The addition of an attention-demanding interference task did not further impede one-legged-stance performance. Although both additional attentional demand and physical fatigue affected postural control in healthy young adults, there was no evidence for an overadditive effect (i.e., fatigue-related performance decrements in postural control were similar under ST and DT conditions). Thus, attentional resources were sufficient to cope with the DT situations in the fatigue condition of this experiment.},
  language  = {en}
}
@misc{WeberPutaLesinskietal.2018,
  author    = {Weber, Stephanie and Puta, Christian and Lesinski, Melanie and Gabriel, Brunhild and Steidten, Thomas and B{\"a}r, Karl-J{\"u}rgen and Herbsleb, Marco and Granacher, Urs and Gabriel, Holger H. W.},
  title     = {Symptoms of anxiety and depression in young athletes using the Hospital Anxiety and Depression Scale},
  series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  number    = {638},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-44560},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-445602},
  pages     = {14},
  year      = {2018},
  abstract  = {Elite young athletes have to cope with multiple psychological demands such as training volume, mental and physical fatigue, spatial separation of family and friends or time management problems may lead to reduced mental and physical recovery. While normative data regarding symptoms of anxiety and depression for the general population is available (Hinz and Brahler, 2011), hardly any information exists for adolescents in general and young athletes in particular. Therefore, the aim of this study was to assess overall symptoms of anxiety and depression in young athletes as well as possible sex differences. The survey was carried out within the scope of the study "Resistance Training in Young Athletes" (KINGS-Study). Between August 2015 and September 2016, 326 young athletes aged (mean +/- SD) 14.3 +/- 1.6 years completed the Hospital Anxiety and Depression Scale (HAD Scale). Regarding the analysis of age on the anxiety and depression subscales, age groups were classified as follows: late childhood (12-14 years) and late adolescence (15-18 years). The participating young athletes were recruited from Olympic weight lifting, handball, judo, track and field athletics, boxing, soccer, gymnastics, ice speed skating, volleyball, and rowing. Anxiety and depression scores were (mean +/- SD) 4.3 +/- 3.0 and 2.8 +/- 2.9, respectively. In the subscale anxiety, 22 cases (6.7\%) showed subclinical scores and 11 cases (3.4\%) showed clinical relevant score values. When analyzing the depression subscale, 31 cases (9.5\%) showed subclinical score values and 12 cases (3.7\%) showed clinically important values. No significant differences were found between male and female athletes (p >= 0.05). No statistically significant differences in the HADS scores were found between male athletes of late childhood and late adolescents (p >= 0.05). To the best of our knowledge, this is the first report describing questionnaire based indicators of symptoms of anxiety and depression in young athletes. Our data implies the need for sports medical as well as sports psychiatric support for young athletes. In addition, our results demonstrated that the chronological classification concerning age did not influence HAD Scale outcomes. Future research should focus on sports medical and sports psychiatric interventional approaches with the goal to prevent anxiety and depression as well as teaching coping strategies to young athletes.},
  language  = {en}
}
@misc{PutaSteidtenBaumbachetal.2018,
  author    = {Puta, Christian and Steidten, Thomas and Baumbach, Philipp and W{\"o}hrl, Toni and May, Rico and Kellmann, Michael and Herbsleb, Marco and Gabriel, Brunhild and Weber, Stephanie and Granacher, Urs and Gabriel, Holger H. W.},
  title     = {Standardized assessment of resistance training},
  series = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe},
  number    = {542},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-42628},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-426289},
  pages     = {11},
  year      = {2018},
  abstract  = {From a health and performance-related perspective, it is crucial to evaluate subjective symptoms and objective signs of acute training-induced immunological responses in young athletes. The limited number of available studies focused on immunological adaptations following aerobic training. Hardly any studies have been conducted on resistance-training induced stress responses. Therefore, the aim of this observational study was to investigate subjective symptoms and objective signs of immunological stress responses following resistance training in young athletes. Fourteen (7 females and 7 males) track and field athletes with a mean age of 16.4 years and without any symptoms of upper or lower respiratory tract infections participated in this study. Over a period of 7 days, subjective symptoms using the Acute Recovery and Stress Scale (ARSS) and objective signs of immunological responses using capillary blood markers were taken each morning and after the last training session. Differences between morning and evening sessions and associations between subjective and objective parameters were analyzed using generalized estimating equations (GEE). In post hoc analyses, daily change-scores of the ARSS dimensions were compared between participants and revealed specific changes in objective capillary blood samples. In the GEE models, recovery (ARSS) was characterized by a significant decrease while stress (ARSS) showed a significant increase between morning and evening-training sessions. A concomitant increase in white blood cell count (WBC), granulocytes (GRAN) and percentage shares of granulocytes (GRAN\%) was found between morning and evening sessions. Of note, percentage shares of lymphocytes (LYM\%) showed a significant decrease. Furthermore, using multivariate regression analyses, we identified that recovery was significantly associated with LYM\%, while stress was significantly associated with WBC and GRAN\%. Post hoc analyses revealed significantly larger increases in participants' stress dimensions who showed increases in GRAN\%. For recovery, significantly larger decreases were found in participants with decreases in LYM\% during recovery. More specifically, daily change-scores of the recovery and stress dimensions of the ARSS were associated with specific changes in objective immunological markers (GRAN\%, LYM\%) between morning and evening-training sessions. Our results indicate that changes of subjective symptoms of recovery and stress dimensions using the ARSS were associated with specific changes in objectively measured immunological markers.},
  language  = {en}
}
@misc{FuehnerGranacherGolleetal.2021,
  author    = {F{\"u}hner, Thea Heidi and Granacher, Urs and Golle, Kathleen and Kliegl, Reinhold},
  title     = {Age and sex effects in physical fitness components of 108,295 third graders including 515 primary schools and 9 cohorts},
  series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  journal   = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe},
  issn      = {1866-8364},
  doi       = {10.25932/publishup-54982},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-549827},
  pages     = {1 -- 13},
  year      = {2021},
  abstract  = {Children's physical fitness development and related moderating effects of age and sex are well documented, especially boys' and girls' divergence during puberty. The situation might be different during prepuberty. As girls mature approximately two years earlier than boys, we tested a possible convergence of performance with five tests representing four components of physical fitness in a large sample of 108,295 eight-year old third-graders. Within this single prepubertal year of life and irrespective of the test, performance increased linearly with chronological age, and boys outperformed girls to a larger extent in tests requiring muscle mass for successful performance. Tests differed in the magnitude of age effects (gains), but there was no evidence for an interaction between age and sex. Moreover, "physical fitness" of schools correlated at r = 0.48 with their age effect which might imply that "fit schools" promote larger gains; expected secular trends from 2011 to 2019 were replicated.},
  language  = {en}
}