Branched-chain amino acids (BCAAs) are known to stimulate the process of protein synthesis. BCAAS combine three amino acids to help form muscle tissue, therefore increasing the likelihood of increasing lean muscle mass. BCAAS can help with training, endurance and muscle recovery. It can be consumed intra-workout or post-workout, depending on the formula. BCAA's are used to prevent muscle breakdown and to ensure muscles are adequately fueled.