Resumen de The Increased Effectiveness of Resistance Training on Unstable vs. Stable Surfaces on Selected Measures of Physical Performance in Young Male Soccer Players
Javier Sánchez Sánchez, Javier Raya González, Rodrigo Ramírez Campillo, Helmi Chaabène, Cristina Petisco Rodríguez, Fábio Yuzo Nakamura
To examine the effects of 10-week (2/wk) resistance training on stable vs. unstable surfaces on selected measures of physical performance in young male soccer players, national-level U19 players participated in this study. They were randomly allocated to an unstable resistance training group (uRT, n = 27) or a stable resistance training group (sRT, n = 28). Before and after the training, horizontal jumping with dominant (Hop D) and nondominant leg (Hop non-D), repeated sprint ability (RSA best time [RSAbest] and RSA mean time [RSAmean]), change-of-direction (COD) speed (Illinois COD test), and aerobic endurance (YoYo Intermittent Recovery Test Level 1 [YoYo IR1]) were assessed. To establish the effects of the interventions on the dependent variables, a 2 (group: uRT and sRT) x 2 (time: pre, post) analysis of variance with repeated measures on time was computed. A significant main effect of time was observed for Hop non-D, RSAbest, and RSAmean (p = 0.003-0.06, effect size [ES] = 0.06-0.15). Furthermore, significant group x time interactions were shown for RSAbest (p = 0.007, ES = 0.13) and RSAmean (p = 0.002, ES = 0.2). Post hoc analysis revealed significant pre- to post-training improvements for RSAbest (p = 0.002, ES = 0.35) and RSAmean (p = 0.0002, ES = 0.36) in the uRT. In the sRT, however, no significant pre-post performance changes were observed in RSAbest and RSAmean. In conclusion, 10 weeks of an in-season resistance training on unstable conditions in addition to regular soccer training was effective in improving repeated-sprint ability performance in youth male elite soccer players including maximal linear sprinting and the ability to perform repeated sprint.
