BCAA consists of 3 specific amino acids. BCAA is for muscle building - and used in endurance sports for regeneration. 

The branched amino acids valine, leucine and isoleucine are summarised under BCAA. They are the only amino acids that can enter the muscles directly through the intestine. All others must first be converted in the liver. This is why BCAA is popular as a dietary supplement, especially among strength and endurance athletes, because the additional intake of BCAA can contribute to improved muscle build-up, less muscle breakdown and delayed fatigue. In addition, BCAA promotes protein synthesis and supports fat loss. There are no side effects as long as the recommended amounts of the food supplement are taken. The human body also absorbs BCAA via protein-containing foods.