Dietary Supplement. Strength Size Recovery BCAA s - Branched Chain Amino Acids - are the 3 unique and essential amino acids leucine, isoleucine, and valine. These are naturally occurring molecules that your body uses to build lean muscle proteins. BCAA s are the only amino acids that are metabolized directly in muscle tissue and help to prevent muscle breakdown, promote muscle protein synthesis, provide fuel for muscular energy, speed muscle recovery, enhance endurance and support anabolic production.* Each serving of AST Sports Science BCAA s deliver you 4550 millgrams of the highest quality branched chain amino acids in easy to swallow, rapid release capsules. Take anytime, anywhere for rapid muscle uptake to endurance recovery and performance.* *These statements have not been evaluated by.