Branched Chain Amino Acids (BCAAs) are specific amino acids that have the most significant role in stimulating protein synthesis since they up regulate enzymes that are responsible for muscle growth.1 BCAAs comprise about 25% of animal protein and occur in a 2:1:1 ratio (leucine: isoleucine: valine) in nature. High quality supplements should reflect this ratio. BCAA supplementation also prevents damage to muscle during exercise. One randomized, placebo controlled study found that those subjects that used BCAAs during and after strenuous exercise has less muscle soreness and faster recovery then those subjects who took a placebo.2
In addition to supporting muscle growth, studies also show that BCAAs aid in the maintenance and production of glycogen, which is responsible for muscle energy and is a stored source of fuel during exercise.3 They also may help to delay the onset of fatigue and maintain mental function in aerobic exercise because BCAAs can compete with tryptophan (a calming amino acid) in the brain that can cause fatigue.4 Some evidence also suggests that BCAAs maintain immune function in athletes.
There is no substantial evidence that BCAAs improve performance, but they do increase recovery in both resistance and aerobic athletes. Due to their muscle protective mechanism, and the fact that BCAA plasma levels peak about 30 minutes after ingestion, they should be supplemented before and after exercise in divided doses.
How can you get BCAAs?
- Directly supplement with BCAAs as a stand alone supplement
- Whey has higher levels of BCAAs than vegan proteins making it a good source
Leave a comment below with why you take BCAAs - or ask any questions you have about adding them to your daily supplements!
1) Mero A: Leucine supplementation and intensive training. Sports Med 1999, 27(6):347-358.
2) Howatson et al. Exercise-induced muscle damage is reduced in resistance-trained males by branched chain amino acids: a randomized, double-blind, placebo controlled study. J Int Soc Sports Nutr. 2012 May 8;9(1):20. [Epub ahead of print]
3) Blomstrand E, Ek S, Newsholme EA: Influence of ingesting a solution of branched-chain amino acids on plasma and muscle concentrations of amino acids during prolonged submaximal exercise. Nutrition 1996, 12(7-8):485-490.
4) Blomstrand E: A role for branched-chain amino acids in reducing central fatigue. J Nutr 2006, 136(2):544S-547S