BCAA, i.e. branched-chain amino acids, are among the most popular supplements used by physically active people. This is because both everyday practice and scientific research confirm their beneficial influence on the generally understood athletic ability. The abbreviation BCAA stands from branched chain amino acids. The name results from the specific structure of these compounds.

BCAA include: leucine, isoleucine and valine which belong to the group of essential amino acids called exogenous, i.e. amino acids that must be provided with food or in the form of a supplement as the body is unable to synthesise them on its own. Unlike other protein-building amino acids, BCAAs are distinguished by their chemical structure and the fact that they are metabolised not in the liver, but primarily in muscle tissue.