This study determined the effects of eight weeks of heavy resistance training combined with branched-chain amino acid (BCAA) supplementation on body composition and muscle performance.
Nineteen non-resistance-trained males resistance-trained (3 sets of 8-10 repetitions) four times/week for eight weeks while also ingesting 9 g/day of BCAA or 9 g/day of placebo (PLAC) on exercise days only (half of total dose 30 min before and after exercise). Data were analyzed with separate 2 x 2 ANOVA (p < 0.05).
For total body mass, neither group significantly increased with training (p = 0.593), and there also were no significant changes in total body water (p = 0.517). Also, no training- or supplement-induced (p = 0.783) changes occurred with fat mass or fat-free mass (p = 0.907). Upper-body (p = 0.047) and lower-body strength (p = 0.044) and upper- (p = 0.001) and lower-body muscle endurance (p = 0.013) were increased with training; however, these increases were not different between groups (p > 0.05).
When combined with heavy resistance training for eight weeks, 9 g/day of BCAA supplementation, half given 30 min before and after exercise, had no preferential effects on body composition and muscle performance.