Whether bodybuilders, fitness fanatics or other strength athletes actually build up extra muscle mass by taking BCAAs depends on the dose. We, the ignoramus compilers of this free webzine, drew this conclusion after reading two older studies on the effect of BCAA supplementation.
The researchers performed an experiment on 54 fit students, of whom most did running or cycling in their free time. The subjects followed a training programme consisting of continuous sessions of 30 and 60 minutes and interval training consisting of four-minute sets. They did this for a period of 11 weeks.
Most of the studies in which lab animals or humans were given BCAAs focus on markers. The researchers looked at molecules that are assumed to reveal how much muscle protein organisms build up or how much fat they break down. But there are few studies in which researchers have just directly measured the amount of strength or muscle bodybuilders built up.
One exception is the study that Mike Spillane presented in 2013 at the annual meeting of the International Society of Sports Nutrition. In that study he got 19 men to do, for the first time in their lives, weight training for eight weeks. [Journal of the International Society of Sports Nutrition 2013, 10(Suppl 1):P25.] [Nutrition and Health 2012, Vol 21(4) 263–273.]
Half of the men took 4.5 g BCAAs half an hour before and half an hour after the training session. So they took a total of 9 g BCAAs per day.
At the end of the trial the subjects who had taken BCAAs had built up more lean body mass than the subjects in the placebo group. What’s more, the subjects in the BCAA group had lost a little bit of fat mass, while the subjects in the placebo group had gained a little bit of fat. But the differences between the groups were not statistically significant.
Four years previously, Jim Stoppani presented a comparable study, also at the annual meeting of the International Society of Sports Nutrition. In that study 36 experienced bodybuilders trained for eight weeks in the same way and followed the same diet.
The researchers divided their subjects into three groups. During the training period one group was given a supplement containing 28 g fast carbohydrates, another a supplement containing 28 g whey, and the third a supplement containing 14 g BCAAs.
The figure below shows that the BCAA group built up more muscle mass and strength than the other groups.
The 2009 study was financed by Scivation by the way. [scivation.com]
If we’re honest, the results of the 2009 study are almost too good to be true. Don’t get us wrong, we absolutely believe that in sufficient quantities, BCAAs can help athletes to maintain and build up muscle mass. But a 4-kg gain in lean body mass in just two months? That’s an awful lot.
Consuming a supplement containing branched-chain amino acids during a resistance-training program increases lean mass, muscle strength and fat loss
A randomized, double-blind study was performed to evaluate the efficacy of consuming a supplement containing branched-chain amino acids (BCAAs) during an eight-week resistance-training program.
Thirty-six strength-trained males with a minimum of two years resistance-training experience (25.5 yrs, 177.7 cm, 85.2 kg and 9.3% body fat) were randomly assigned to receive either 14 grams of BCAAs (n = 12), 28 grams of whey protein (n = 12), or 28 grams of carbohydrates from a sports drink (n = 12) while performing an eight-week resistance-training program. Participants followed a periodized, whole-body training program that involved training all major muscle groups once per week using a four-day training split. Subjects body weight, body composition, and 10-rep max on the bench press and squat were determined before and after the eight-week training program. Subjects followed a standardized diet while following the program.
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). Conclusion Ingestion of a supplement containing BCAAs while following an 8-week resistance training program resulted in a greater decrease in percent body fat, an increase in lean mass, and 10-RM strength gains on the bench press and squat vs. ingestion of a whey supplement or a sports drink. In addition, the ingestion of a whey protein supplement resulted in greater lean mass gains than ingestion of a sports drink. Source: http://www.jissn.com/content/6/S1/P1