BCAA amino acids (abbreviation for English « branched - chain amino acids "- amino acids with branched side branches) - one of the essential food supplements of any bodybuilder The BCAA amino acids, which differ in an atypical branching structure, include leucine, isoleucine, and also valine. As you know, our body alone is able to produce only part of the necessary amino acids, while others, without which it also cannot exist, must enter it from the outside.