@article{KunzZinnerHolmbergetal.2019, author = {Kunz, Philipp and Zinner, Christoph and Holmberg, Hans-Christer and Sperlich, Billy}, title = {Intra- and post-match time-course of indicators related to perceived and performance fatigability and recovery in elite youth soccer players}, series = {Frontiers in Physiology}, volume = {10}, journal = {Frontiers in Physiology}, number = {1383}, issn = {1664-042X}, doi = {10.3389/fphys.2019.01383}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-195657}, year = {2019}, abstract = {PurposeOur aims were to examine (i) the internal load during simulated soccer match-play by elite youth players; and (ii) the time-course of subsequent recovery from perceived and performance fatigability. MethodsEleven male youth players (16 ± 1 years, 178 ± 7 cm, 67 ± 7 kg) participated in a 2 × 40-min simulated soccer match, completing 30 rounds (160 s each) with every round including multidirectional and linear sprinting (LS20m), jumping (CMJ) and running at different intensities. During each round, LS20m, CMJ, agility, heart rate (HR), oxygen uptake (VO2), energy expenditure (EE), substrate utilization and perceived exertion RPE were assessed. In addition, the blood level of lactate (Lac) was obtained after each of the five rounds. Creatine kinase (CK) concentration, maximal voluntary isometric knee extension and flexion, CMJ, number of skippings in 30 s, and subjective ratings on the Acute Recovery and Stress Scale (ARSS) were examined before and immediately, 24 and 48 h after the simulation. Results: During the game \%HR\(_{peak}\) (p < 0.05, d = 1.08), \%VO2\(_{peak}\) (p < 0.05; d = 0.68), Lac (p < 0.05, d = 2.59), RPE\(_{total}\) (p < 0.05, d = 4.59), and RPE\(_{legs}\) (p < 0.05, d = 4.45) all increased with time during both halves (all p < 0.05). Agility improved (p < 0.05, d = 0.70) over the time-course of the game, with no changes in LS20m (p ≥ 0.05, d = 0.34) or CMJ (p ≥ 0.05, d = 0.27). EE was similar during both halves (528 ± 58 vs. 514 ± 61 kcal; p = 0.60; d = 0.23), with 62\% (second half: 65\%) carbohydrate, 9\% (9\%) protein and 26\% (27\%) fat utilization. With respect to recovery, maximal voluntary knee extension (p ≥ 0.05, d = 0.50) and flexion force (p ≥ 0.05, d = 0.19), CMJ (p ≥ 0.05, d = 0.13), number of ground contacts (p ≥ 0.05, d = 0.57) and average contact time (p ≥ 0.05, d = 0.39) during 30-s of skipping remained unaltered 24 and 48 h after the game. Most ARSS dimensions of load (p < 0.05, d = 3.79) and recovery (p < 0.05, d = 3.22) returned to baseline levels after 24 h of recovery. Relative to baseline values, CK was elevated immediately and 24 h after (p < 0.05, d = 2.03) and normalized 48 h later. ConclusionIn youth soccer players the simulated match evoked considerable circulatory, metabolic and perceptual load, with an EE of 1042 ± 118 kcal. Among the indicators of perceived and performance fatigability examined, the level of CK and certain subjective ratings differed considerably immediately following or 24-48 h after a 2 × 40-min simulated soccer match in comparison to baseline. Accordingly, monitoring these variables may assist coaches in assessing a U17 player's perceived and performance fatigability in connection with scheduling training following a soccer match.}, language = {en} } @article{WallmannSperlichHoffmannSaldittetal.2019, author = {Wallmann-Sperlich, Birgit and Hoffmann, Sophie and Salditt, Anne and Bipp, Tanja and Froboese, Ingo}, title = {Moving to an "active" biophilic designed office workplace: a pilot study about the effects on sitting time and sitting habits of office-based workers}, series = {International Journal of Environmental Research and Public Health}, volume = {16}, journal = {International Journal of Environmental Research and Public Health}, number = {9}, issn = {1660-4601}, doi = {10.3390/ijerph16091559}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-197371}, pages = {1559}, year = {2019}, abstract = {Promising initial insights show that offices designed to permit physical activity (PA) may reduce workplace sitting time. Biophilic approaches are intended to introduce natural surroundings into the workplace, and preliminary data show positive effects on stress reduction and elevated productivity within the workplace. The primary aim of this pilot study was to analyze changes in workplace sitting time and self-reported habit strength concerning uninterrupted sitting and PA during work, when relocating from a traditional office setting to "active" biophilic-designed surroundings. The secondary aim was to assess possible changes in work-associated factors such as satisfaction with the office environment, work engagement, and work performance, among office staff. In a pre-post designed field study, we collected data through an online survey on health behavior at work. Twelve participants completed the survey before (one-month pre-relocation, T1) and twice after the office relocation (three months (T2) and seven months post-relocation (T3)). Standing time per day during office hours increased from T1 to T3 by about 40 min per day (p < 0.01). Other outcomes remained unaltered. The results suggest that changing office surroundings to an active-permissive biophilic design increased standing time during working hours. Future larger-scale controlled studies are warranted to investigate the influence of office design on sitting time and work-associated factors during working hours in depth.}, language = {en} } @article{KunzAzadEngelHolmbergetal.2019, author = {Kunz, Philipp and Azad Engel, Florian and Holmberg, Hans-Christer and Sperlich, Billy}, title = {A meta-comparison of the effects of high-intensity interval training to those of small-sided games and other training protocols on parameters related to the physiology and performance of youth soccer players}, series = {Sports Medicine - Open}, volume = {5}, journal = {Sports Medicine - Open}, doi = {10.1186/s40798-019-0180-5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-200332}, pages = {7}, year = {2019}, abstract = {Background High-intensity interval training (HIIT) is frequently employed to improve the endurance of various types of athletes. To determine whether youth soccer players may benefit from the intermittent load and time efficiency of HIIT, we performed a meta-analysis of the relevant scientific literature. Objectives Our primary objective was to compare changes in various physiological parameters related to the performance of youth soccer players in response to running-based HIIT to the effects of other common training protocols (i.e., small-sided games, technical training and soccer-specific training, or high-volume endurance training). A secondary objective was to compare specifically running-based HIIT to a soccer-specific form of HIIT known as small-sided games (SSG) in this same respect, since this latter type of training is being discussed extensively by coaches. Method A systematic search of the PubMed, SPORTDiscus, and Web of Science databases was performed in August of 2017 and updated during the review process in December of 2018. The criteria for inclusion of articles for analysis were as follows: (1) comparison of HIIT to SSG or some other training protocol employing a pre-post design, (2) involvement of healthy young athletes (≤ 18 years old), and (3) assessment of variables related to endurance or soccer performance. Hedges' g effect size (dppc2) and associated 95\% confidence intervals for the comparison of the responses to HIIT and other interventions were calculated. Results Nine studies, involving 232 young soccer players (mean age 16.2 ± 1.6 years), were examined. Endurance training in the form of HIIT or SSG produced similar positive effects on most parameters assessed, including peak oxygen uptake and maximal running performance during incremental running (expressed as Vmax or maximal aerobic speed (MAS)), shuttle runs (expressed as the distance covered or time to exhaustion), and time-trials, as well as submaximal variables such as running economy and running velocity at the lactate threshold. HIIT induced a moderate improvement in soccer-related tests involving technical exercises with the soccer ball and other game-specific parameters (i.e., total distance covered, number of sprints, and number of involvements with the ball). Neuromuscular parameters were largely unaffected by HIIT or SSG. Conclusion The present meta-analysis indicates that HIIT and SSG have equally beneficial impacts on variables related to the endurance and soccer-specific performance of youth soccer players, but little influence on neuromuscular performance.}, language = {en} } @article{EngelWagnerSchelhornetal.2019, author = {Engel, Florian A. and Wagner, Matthias Oliver and Schelhorn, Franziska and Deubert, Felix and Leutzsch, Sascha and Stolz, Alexander and Sperlich, Billy}, title = {Classroom-Based Micro-Sessions of Functional High-Intensity Circuit Training Enhances Functional Strength but Not Cardiorespiratory Fitness in School Children — A Feasibility Study}, series = {Frontiers in Public Health}, volume = {7}, journal = {Frontiers in Public Health}, number = {291}, issn = {2296-2565}, doi = {10.3389/fpubh.2019.00291}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-195669}, year = {2019}, abstract = {The present study assessed the short-term effect of 6 min classroom-based micro-sessions of multi-joint functional high-intensity circuit training (FunctionalHIIT) performed by students during regular classes on parameters related to functional strength and cardiorespiratory fitness. In this randomized controlled 4-week study, 17 students (11 male; 6 female; age: 11.6 ± 0.2 years) performed 6 min of FunctionalHIIT (targeting >17 on the Borg scale) 4 days per week during regular school classes and 18 students (11 male; 7 female; age: 11.7 ± 0.3 years) served as control group (CG) without any additional in-class physical activity. The FunctionalHIIT group completed 86\% of all planned sessions (mean duration: 6.0 ± 1.5 min) with a mean RPE of 17.3 ± 2.1. Body height, mass and BMI did not differ between the groups at baseline or between pre- and post-testing (p > 0.05; eta2 ≤ 0.218). The performances in lateral jumping (p < 0.000; part eta2 = 0.382; Δ\% 4.6 ± 8.6), sit-ups (p < 0.000; part eta2 = 0.485; Δ\% 3.1 ± 8.6) and 20-m sprints (p < 0.000; part eta2 = 0.691; Δ\% 15.8 ± 5.4) improved in both groups with greater increase following FunctionalHIIT. No baseline differences and no interaction effects occurred in performance of 6 min run, flexibility, push-ups, balance, and long jump. Classroom-based FunctionalHIIT sessions, performed 4 days per week during 4 weeks did not improve variables related to aerobic endurance performance but enhanced certain parameters of functional strength in schoolchildren. As time is limited in the educational system of schools, FunctionalHIIT during regular school classes could offer a new perspective for increasing functional strength in schoolchildren.}, language = {en} }