All groups had a 100% compliance with the study protocol. The BCAA group experienced a significantly greater gain in body weight than the whey group (2 ± 1 kg vs. 1 ± 1 kg; p < 0.02) and the carbohydrate group (2 ± 1 kg vs. 1 ± 1 kg; p < 0.01). For lean mass, the BCAA group gained significantly greater lean mass than the whey group (4 ± 1 kg vs. 2 ± 1 kg; p < 0.01) and the carbohydrate group (4 ± 1 kg vs. 1 ± 1 kg; p < 0.01). The whey group also gained significantly more lean mass than the carbohydrate group (2 ± 1 kg vs. 1 ± 1 kg; p < 0.02). BCAA group decreased their percent body fat significantly more than the whey group (2 ± 1% vs. 1 ± 1%; p = 0.039) and the carbohydrate group (2 ± 1% vs. 1 ± 1%; p < 0.01). Muscular strength was significantly greater in the BCAA group on the 10-RM bench press than the whey group (6 ± 3 kg vs. 3 ± 2 kg; p < 0.01) and the carbohydrate group (6 ± 3 kg vs. 2 ± 2 kg; p < 0.01). For the squat, the BCAA group gained significantly more strength on their 10-RM than the whey group (11 ± 5 kg vs. 5 ± 3 kg; p < 0.01) and the carbohydrate group (11 ± 5 kg vs. 3 ± 2 kg; p < 0.01).