Effects of BCAA/glutamine in addition to protein intake
Posted: Mon Feb 21, 2011 12:44 pm
Effects of supplemental protein on body composition and muscular strength in healthy athletic male adults
Objective: The purpose of this double-blind, randomized study was to assess the effects of supplemental whey protein with or without added L-glutamine and branched-chain amino acids on body mass, body composition, and exercise performance for a 10-week period.
Methods: Sixteen healthy athletic male adults were separated into 2 groups where they received either whey protein 40 g/d (group 1) or a combination of 40 g of whey protein with 5 g of L-glutamine and 3 g of branched-chain amino acids (leucine, isoleucine, and valine) per day (group 2). Each subject was instructed to follow a diet, created by a registered dietitian, that restricted food protein intake to 1.6 g/kg body weight. In addition, all participants engaged in hypertrophy resistance exercise training under the guidance of an exercise physiologist. At baseline, week 5, and week 10, each subject underwent body composition and exercise performance testing.
Results: Compared with group 1, group 2 gained a significant amount of body mass (1.25 kg; P ≤ 0.05) over the 10 weeks. During the first 5 weeks, group 2 gained a significant amount of fat-free mass (0.72 kg; P = 0.05) compared with group 1. At 10 weeks, group 2 exhibited a trend toward gaining fat-free mass (1.6 kg). No significant changes were noted comparatively for change in percent body fat. In terms of exercise performance (bench press repetitions), group 2 improved significantly (P = 0.001) compared with group 1 after 10 weeks of supplementation. Group 2 also exhibited a trend over 10 weeks compared with group 1 for improvement in leg press repetitions (9.13 vs 5.13).
Conclusions: Results of the present study suggest that whey protein combined with glutamine and branched-chain amino acids, in addition to resistance exercise, leads to improved body composition and exercise performance.
Objective: The purpose of this double-blind, randomized study was to assess the effects of supplemental whey protein with or without added L-glutamine and branched-chain amino acids on body mass, body composition, and exercise performance for a 10-week period.
Methods: Sixteen healthy athletic male adults were separated into 2 groups where they received either whey protein 40 g/d (group 1) or a combination of 40 g of whey protein with 5 g of L-glutamine and 3 g of branched-chain amino acids (leucine, isoleucine, and valine) per day (group 2). Each subject was instructed to follow a diet, created by a registered dietitian, that restricted food protein intake to 1.6 g/kg body weight. In addition, all participants engaged in hypertrophy resistance exercise training under the guidance of an exercise physiologist. At baseline, week 5, and week 10, each subject underwent body composition and exercise performance testing.
Results: Compared with group 1, group 2 gained a significant amount of body mass (1.25 kg; P ≤ 0.05) over the 10 weeks. During the first 5 weeks, group 2 gained a significant amount of fat-free mass (0.72 kg; P = 0.05) compared with group 1. At 10 weeks, group 2 exhibited a trend toward gaining fat-free mass (1.6 kg). No significant changes were noted comparatively for change in percent body fat. In terms of exercise performance (bench press repetitions), group 2 improved significantly (P = 0.001) compared with group 1 after 10 weeks of supplementation. Group 2 also exhibited a trend over 10 weeks compared with group 1 for improvement in leg press repetitions (9.13 vs 5.13).
Conclusions: Results of the present study suggest that whey protein combined with glutamine and branched-chain amino acids, in addition to resistance exercise, leads to improved body composition and exercise performance.