The purpose of this study was to examine the effects of acute creatine-monohydrate supplementation on soccer-specific performance in young soccer players. Twenty young male soccer players (16.6 ± 1.9 years) participated in the study and were matched and allocated to 2 randomly assigned trials: ingesting creatine-monohydrate supplement (3 × 10-g doses) or placebo for 7 days. Before and after the supplementation protocol, each subject underwent a series of soccer-specific skill tests: dribble test, sprint-power test, endurance test, and vertical jump test. Specific dribble test times improved significantly in the creatine group (13.0 ± 1.5 vs. 10.2 ± 1.8 s; p < .05) after supplementation protocol. Sprint-power test times were significantly improved after creatine-monohydrate supplementation (2.7 ± 0.4 vs. 2.2 ± 0.5 s; p < .05) as well as vertical jump height (49.2 ± 5.9 vs. 55.1 ± 6.3 cm; p < .05) in creatine trial. Furthermore, dribble and power test times, along with vertical jump height, were superior in creatine versus placebo trial (p < .05) at post-supplementation performance. There were no changes in specific endurance test results within or between trials (p > .05). There were no between-trial differences in the placebo trial (p > .05). The main finding of the present study indicates that supplementation with creatine in young soccer players improved soccer-specific skill performance compared with ingestion of placebo.
Sergej M. Ostojic
Laurie-Anne Marquet, Christophe Hausswirth, Arnaud Hays, Fabrice Vettoretti, and Jeanick Brisswalter
To assess the impact of between-training-sessions recovery strategies (passive [PAS], active [ACT], cold-water immersion [CWI], and ingestion of a recovery drink [NUTR]) on maximal cycling performance, perceptions of delayed-onset muscle soreness (DOMS), and fatigue in world-class BMX riders.
Eleven elite BMX athletes, members of the French national team (top country in the 2011 international ranking, 4 medals at the 2012 World Championships, top European country), participated in the study, which involved standardized training periods. Athletes performed 3 maximal-sprint power tests: the first day of the week before the training session and before and after training on the third day of the week (D3). The recovery strategy was randomly assigned to each participant on day 2 immediately after the last training period of the day. Perceptions of DOMS and general fatigue were recorded on D3.
After training on D3, the decrease in maximal-sprint power (Pmax) was significantly greater for PAS than with CWI (P = .02) and NUTR (P = .018). Similar results were found with ACT (vs CWI P = .044, and vs NUTR P = .042). Self-reported DOMS and fatigue were significantly greater after PAS than after other strategies.
For elite BMX riders, between training days, nutritional and/or CWI recovery strategies appear to be best for reducing muscle fatigue and increasing the capacity to withstand the training schedule.