Amino acids are the building blocks of protein that aid in repair, growth, and development of muscle tissue. Among the most beneficial amino acids for athletes in hard training or for those individuals trying to shed body fat whilst simultaneously retaining lean muscle are the three branched-chain amino acids (BCAA’s). These are the essential amino acids L-Leucine, L-Isoleucine, and L-Valine.

There is extensive research documenting the key role(s) of branched-chain amino acids (BCAA’s) on the activity and composition of muscle tissue. BCAA's are vital substrates for other amino acids, and are released in large quantities during intense exercise, where they are used by muscle tissue for fuel. This in turn spares other amino acids from being catabolised from muscle tissue. This anti-catabolic effect is as a result of the fact that BCAA’s are precursors to keto acids, glutamine, alpha-ketoglutarate and other key metabolites in cellular energy production.

Research indicates that BCAA supplementation taken before training, has an anti-catabolic (muscle preserving) effect by helping to spare muscle BCAA reserves as well as by positively impacting on testosterone levels during and after training.
An example of such research recently presented at the National Strength & Conditioning Associations annual conference examined the relationship of BCAA supplementation to muscle gains over a 4 week period. Subjects supplemented with BCAA’s whilst engaging in intense weight training sessions. Compared with the placebo group, the subjects supplementing with BCAA’s displayed lower levels of enzymes associated with muscle damage and also lower levels of cortisol, the body’s primary catabolic hormone. In addition they displayed consistently higher testosterone levels than the subjects in the placebo group.

BCAA oxidation (i.e muscle burning) in muscle is concurrent to fatty acid oxidation (i.e. burning of body fat) so when you exercise to burn fat as an energy source (i.e during cardio training), the burning of muscle BCAA’s increases simultaneously. BCAA’s taken before you exercise therefore exerts a sparing action on muscle protein, which is especially beneficial during periods of calorie restriction where one is trying to shed body fat.

Conclusion:
For maximum lean muscle preserving support, especially whilst dieting, ensure adequate branched chain amino acid intake by supplementing with a BCAA supplement such as SPS Retain Muscle before training as well as by using SPS Lean Muscle Protein Matrix, which is naturally rich in BCAA’s, as your protein powder of choice.

References:
Excerpt - National Strength and Conditioning Association’s annual conference, 2006
Nassif AC, Naylor EW. Immediately elevated serum branched-chain amino acids following effective GI decomposition and enteral feeding. Nutrition 12: 159-162, 1996.
Eur J Appl Physiol 1991;63:83-88 / J Appl Physiol 1996;81:2644-2650 / Acta Physiol Scand. 1997;159:41-49.