Branched Chain Amino Acids

Branched chain amino acids

Branched-chain amino acids (BCAA) are essential amino acids (specifically, valine, leucine and isoleucine). They are essential, meaning we must get them in our diet because our bodies do not produce them. Branched chain amino acids have various functions related to energy production during and after exercise so they are needed in adequate amounts, but not excessive.

BCAA are often used to prevent fatigue and improve concentration. But the most relevant to you, perhaps, is the common practice of taking BCAAs to improve exercise performance and reduce muscle breakdown. While the first use has a fair amount of sceptics, the second is widely accepted in the medical world.

Exercise causes an increase in serotonin levels, which are believed to cause fatigue. But BCAAs are believed to reduce serotonin levels, and thus cancel out the fatigue and actually enhance exercise performance. This has been found in resistance training exercises but not in endurance events like black belt grading although this is controversial with some studies finding no difference. Some studies also suggest that peak power performance is also increased by the use of BCAA but this also has some differences of opinion. There is a balance needed to gain benefits from BCAA too much will cause you to fatigue faster and can interfere with the absorption of other amino acids.

BCAAs are metabolized primarily in skeletal muscles, while other amino acids are metabolized in the liver, which is why some think they must take BCAA supplements if they're engaging in strenuous exercise to reduce muscle breakdown. With that in mind, BCAAs are often touted to help repair damaged muscles, decrease muscle soreness and increase muscle function. Some data shows that BCAA supplementation before and after exercise has beneficial effects for decreasing exercise-induced muscle damage and promoting muscle-protein synthesis.

Studies like this one and many others lead experts to believe it's possible to consider BCAA as a useful supplement for muscle recovery.

BCAAs appear to be safe for most healthy people. If you have liver, kidney problems or a history of depression consult a health care professional before taking BCAA.

Lack of regulation of supplements means that there is no guarantee that what the supplier says is in the product is actually in the product and also there may be contamination problems with supplements. This is especially important if you are a professional athlete due to being held accountable to anything that is present in your body no matter how it got there.

The body obtains BCAAs from proteins found in food, especially meat, dairy products and legumes. A balanced diet with adequate protein provides enough BCAAs, even for the strenuous exerciser. Nitrogen balance studies have shown that no amount above 2.0 grams of protein per kilogram of body weight is beneficial. And just because experts believe BCAAs help prevent muscle breakdown doesn't mean it's necessary. As long as you're getting enough dietary macronutrients, such as proteins, fat and carbohydrates, the muscle will be spared. If you do decide to take BCAA supplements, make sure they're from a reliable company. Also, pay attention to how you feel while taking them.

References

Bishop, D., 2010. Dietary suplements and team sports performance. Sports Med, 40(12), pp. 995-1017.

Blomstrand, E., 2001. Amino acids and central fatigue. Amino Acids, Volume 20, p. 25–34.

Blomstrand, E., 2006. A Role for Branched-Chain Amino Acids in Reducing Central Fatigue. The Journal of Nutrition, Volume 136, p. 544S–547S.

Blomstrand, E., Eliasson, J., Karlsson, H. & Kohnke, R., 2006. Branched-Chain Amino Acids Activate Key Enzymes in Protein Synthesis after Physical Exercise. The Journal of Nutrition, Volume 136, p. 269S–273S.

Burke, L. M., Castell, L. M. & Stear, S. J., 2009. BJSM reviews: A - Z of supplements: dietary supplements, sports nutrition foods and ergogenic aids for health and performance. British Journal of Sports Medicine, Volume 43, pp. 728-810.

Greer, B. K., White, J. P., Arguello, E. M. & Haymes, E. M., 2011. Branched-chain amino acid supplementation lowers perceived exertion but does not affect performance in untrained males. Journal of Strength and Conditioning Research, 25(2), p. 539–544.

Knechtle, B. et al., 2011. No effect of short-term amino acid supplementation on variables related to skeletal muscle damage in 100 km ultra-runners: A randomized controlled trial. Journal of the International Society of Sports Nutrition, 8(6).

Ohtani, M., Sugita, M. & Maruyama, K., 2006. Amino Acid Mixture Improves Training Efficiency in Athletes. Journal of Nutrition, Volume 136, p. 538S–543S.

Portier, H. et al., 2008. Effects of branched-chain amino acids supplementation on physiological and psychological performance during an offshore sailing race. European Journal of Applied Physiology, Volume 104, p. 787–794.

Ratamess, N. A. et al., 2003. The effects of amino acid supplementation on muscular performance during resistance training overreaching. Journal of Strength and Conditioning Research, 17(2), p. 250–258.

Shimomura, Y. et al., 2006. Nutraceutical Effects of Branched-Chain Amino Acids on Skeletal Muscle. The Journal of Nutrition, Volume 136, p. 529S–532S.

Williams, M., 2005. Dietary supplements and sports performance: Amino acids. Journal of the International Society of Sports Nutrition, 2(2), pp. 63-67.

{snippet author_teresa-roberts}