Don't short-change your muscle-building progress—fuel up for maximum gains with Swanson Branched-Chain Amino Acids. Essential building blocks for protein synthesis, branched-chain amino acids play vital roles in muscle growth and recuperation. Our advanced formula features three branched-chain amino acids, L-leucine, L- isoleucine and L-valine, fortified with a generous supply of vitamin B6 to enhance their metabolism.