Branch Chain Amino Acids, often known as BCAA’s are the most important amino acids in the chain of protein. The three amino acids that make up BCAA’s are Leucine, Isoleucine, and valine. It is understood that exercise causes BCAA catabolism and therefore BCAA requirement is increased by exercise (1). BCAA supplementation before and after exercise may help reduce exercised induced muscle damage and promote muscle protein synthesis (1). Preventing muscle breakdown is important for those who are dieting and those who are trying to build muscle. While BCAA supplementation isn’t the only way to do this (BCAA’s are also in meats, protein, and dairy), studies show it may help reduce soreness and start the rebuilding process early when taken immediately after a workout (2). One Study in 2019 even showed an increase in immune response from athletes who supplemented with BCAA’s (3)


Essential Amino Acids are composed of the three branch chains, plus an additional 6 amino acids. Those 6 are Tryptophan, Threonine, Phenylalanine, Methionine, Lysine, and Histidine. Recent studies show that EAA formulas may stimulate post-exercise muscle protein synthesis more than BCAA’s alone, however the main reason for this is still attributed to the role of the BCAA’s (4). The same study also shows that after 180 minutes following exercise, there is little difference in muscle protein synthesis. 

  1. Shimomura Y, Murakami T, Nakai N, Nagasaki M, Harris RA. Exercise promotes BCAA catabolism: effects of BCAA supplementation on skeletal muscle during exercise. J Nutr. 2004 Jun;134(6 Suppl):1583S-1587S. doi: 10.1093/jn/134.6.1583S. PMID: 15173434.
  2. Fedewa MV, Spencer SO, Williams TD, Becker ZE, Fuqua CA. Effect of branched-Chain Amino Acid Supplementation on Muscle Soreness following Exercise: A Meta-Analysis. Int J Vitam Nutr Res. 2019 Nov;89(5-6):348-356. doi: 10.1024/0300-9831/a000543. Epub 2019 Apr 2. PMID: 30938579.
  3. Trushina EN, Vybornov VD, Riger NA, Mustafina OK, Solntsevа TN, Timonin AN, Zilova IS, Radzhabkadiev RM. [The efficiency of branched chain amino acids (BCAA) in the nutrition of combat sport athletes]. Vopr Pitan. 2019;88(4):48-56. Russian. doi: 10.24411/0042-8833-2019-10041. Epub 2019 Jul 15. PMID: 31722141.
  4. Moberg M, Apró W, Ekblom B, van Hall G, Holmberg HC, Blomstrand E. Activation of mTORC1 by leucine is potentiated by branched-chain amino acids and even more so by essential amino acids following resistance exercise. Am J Physiol Cell Physiol. 2016 Jun 1;310(11):C874-84. doi: 10.1152/ajpcell.00374.2015. Epub 2016 Apr 6. PMID: 27053525.