Prolab® BCAA Plus provides the essential amino acids L-Leucine, L-Valine and L-Isoleucine. These three protein-sparing amino acids are known as branched chain. It is a well known fact that amino acids are responsible for protein synthesis, hence the nickname building blocks. Studies show BCAAs are important for muscle growth and recuperation. Muscle production depends on an increase in protein synthesis. BCAAs are important in your quest for muscle growth and recuperation. Your body cannot manufacture its own BCAAs they must be supplied through your diet. Do not short change your progress, use BCAA Plus