BCAAs: The Facts

Branched-chain amino acids (BCAAs) have long been promoted as a supplement to enhance muscle growth and recovery. However, recent studies suggest that BCAAs may not be as effective as once thought, and that essential amino acids (EAAs) may be a better alternative. BCAAs are comprised of three amino acids – leucine, isoleucine, and valine – that are often used by athletes and bodybuilders to reduce muscle fatigue and promote muscle protein synthesis. However, while leucine is believed to be the most important of the three for muscle growth, taking BCAAs alone may not provide enough of the other EAAs that are also necessary for protein synthesis. One study published in the Journal of the International Society of Sports Nutrition found that supplementing with BCAAs alone did not lead to any significant improvements in muscle mass or strength compared to a placebo group. Another study published in the American Journal of Clinical Nutrition also found that supplementing with BCAAs did not result in any additional muscle protein synthesis in healthy young adults. On the other hand, EAAs contain all nine essential amino acids that are necessary for muscle protein synthesis. Studies have shown that supplementing with EAAs can lead to increased muscle protein synthesis and improved muscle recovery. One study published in the Journal of the International Society of Sports Nutrition found that supplementing with EAAs led to greater muscle protein synthesis compared to supplementing with BCAAs alone. While BCAAs may have some benefits for reducing muscle fatigue, they may not be as effective as once thought for promoting muscle growth. EAAs, on the other hand, contain all the necessary amino acids for muscle protein synthesis and may be a better alternative for those looking to enhance muscle growth and recovery. As always, it’s important to speak with a healthcare professional before starting any new supplement regimen. Sources: Kim, D. H., Kim, S. H., Jeong, W. S., & Lee, H. Y. (2013). Effect of BCAA intake during endurance exercises on fatigue substances, muscle damage substances, and energy metabolism substances. Journal of exercise nutrition & biochemistry, 17(4), 169-180. Jackman, S. R., Witard, O. C., Philp, A., Wallis, G. A., Baar, K., & Tipton, K. D. (2017). Branched-chain amino acid ingestion stimulates muscle myofibrillar protein synthesis following resistance exercise in humans. Frontiers in physiology, 8, 390. Churchward-Venne, T. A., Burd, N. A., Mitchell, C. J., West, D. W., Philp, A., Marcotte, G. R., … & Phillips, S. M. (2012). Supplementation of a suboptimal protein dose with leucine or essential amino acids: effects on myofibrillar protein synthesis at rest and following resistance exercise in men. The Journal of physiology, 590(11), 2751-2765. Moberg, M., Apró, W., Ohlsson, T., Pontén, M., Villanueva, A., & Ekblom, B. (2016). Resistance exercise-induced S6K1 kinase activity is not inhibited in human skeletal muscle despite prior activation of AMPK by high-intensity interval cycling. American Journal of Physiology-Endocrinology and Metabolism, 311(3), E587-E594. Tipton, K. D., Ferrando, A. A., Phillips, S. M., Doyle Jr, D., & Wolfe, R. R. (1999). Post