The branched-chain amino acids (BCAA), L-leucine, L-isoleucine, & L-valine, are probably the most essential amino acids for athletes in training. They account for 33% of muscle protein. Some experts believe that even moderate exercise can increase your bodys needs for leucine by up to 240%BCAAs are a great way to assist your overall fitness goals, convenient & effective! Many studies showing great results from using them & good overall value also.