Single-Leg Power Output and Between-Limbs Imbalances in Team-Sport Players: Unilateral Versus Bilateral Combined Resistance Training

Purpose: To compare the effects of unilateral and bilateral resistance training on single-leg power output, between-limbs imbalance (BLI), bilateral deficit (BLD), change of direction (COD), and linear sprinting and jumping performance in young elite basketball players. Methods: Twenty-two young(U-16 U-19) male basketball players were randomly assigned either to an exclusive unilateral (UNI) (n = 11) or a bilateral (BIL) (n = 11) resistance training group during a 6-wk period. Both groups training consisted of 3 unilateral or bilateral 900 back-squat sets. A postdetermined number of repetitions was set until power output dropped to <10% of maximum power (MP) output. In addition, both groups performed 2 sets of 5 unilateral or bilateral drop jumps and 2 sets of 5 unilateral or bilateral countermovement jumps (CMJ). Pre-and posttraining, performance was assessed by an incremental bilateral and unilateral squat-load test, a multiple-COD test (V-cut test), a 15-m-sprint test (7.5 + 7.5 m) with one 180 COD performed with both right (180 degrees RCOD) and left (180 degrees LCOD) legs, a 25 m sprint test (5-and 15-m split time), and a CMJ test. Results: Within group analyses showed substantial improvements in 180 degrees RCOD, bilateral and unilateral MP, 25 m sprint test, and CMJ in both groups. Between groups analyses showed substantially better results in 180 degrees LCOD, MP with right and left legs, BLI, and BLD in UNI than in BEL. Conclusions: Both training programs substantially improved most of the physical fitness tests, but only UNI reduced between limbs asymmetry and achieved greater enhancements in actions that mostly required applying force unilaterally in basketball players.