Disclaimer: The information contained in this article is for educational purposes only and is not meant to constitute or substitute for medical advice. For more information on taking BCAA supplements please consult your health provider or trainer.
Should athletes take branched chain amino acid supplements to improve their appearance and performance? Branched chain amino acids (BCAA) are essential proteins that the body derives from foods like meat, legumes and dairy products. BCAA have been found to help in muscle repair, increasing endurance for high intensity workouts and in reducing muscle breakdown, giving them an important role in exercise and sports. Here is more information about branched chain amino acids and the benefits of BCAA supplements.
What are BCAA?
Branched chain amino acids (BCAA) are building blocks of proteins that are found essentially in the diet, mainly from meat, dairy products and legumes. Aside from meat products, it can also be found in soy, fish, nuts and wheat germ. They are composed of three types of amino acids: leucine, isoleucine, and valine. These essential amino acids are not synthesized by the body and have to be taken from the diet or from supplements.
BCAA are molecules of proteins that have branched chains in their chemical structure, and have important uses in medicine. These amino acids have anabolic effects, meaning they build up muscles and tissues through synthesis, growth and differentiation of cells, resulting in an increase in body size. They have also been found to decrease the rate of protein degradation in resting human muscle, and have thus been found to be important in treating many conditions. Of the three BCAA, leucine is the most important building block of protein synthesis.
Benefits of BCAA
Branched chain amino acids have important medical uses, including the treatment of brain involvement in liver disease and for improving symptoms associated with mania and tardive dyskinesia. BCAA are used to help slow down muscle wasting in people who are confined to bed, and have also been found to help in improving the appetite and nutrition of elderly patients on hemodialysis.
Researchers have found in recent years that BCAA have other benefits that may be important to athletes. Studies have shown that:
- Supplemental BCAA, particularly leucine, have an anabolic effect on muscles at rest, by increasing protein synthesis and reducing the rate of muscle degradation.
- Supplemental intake of leucine after performing resistance exercises result in a positive protein balance, where the rate of protein synthesis surpasses the rate of protein breakdown.
- Taking of BCAA nutritional supplements directly after endurance exercise (like running) stimulates protein synthesis in the recovery period.
- Supplemental BCAA intake before and after exercise is beneficial for decreasing exercise-induced muscle damage and promoting muscle-protein synthesis
These findings show that BCAA may be a useful supplement in relation to exercise and sports. However, data are still lacking on the effects of BCAA in improving athletic performance.
According to studies, the estimated average requirement of BCAA is 68 mg/kg/day (leucine 34 mg, isoleucine 15 mg, valine 19 mg) for adults, although some researchers think this may have been underestimated, and that the requirement is really about 144 mg/kg/day.
Although BCAA can be found in foods usually taken in one’s diet, they are available only in small amounts, and one would have to consume a lot of meat, for instance, to obtain the benefits. This is often why people consider nutritional food supplements. Other disadvantages of relying on dietary foods as a source of BCAA include high cost, inconvenience and the high cholesterol content that comes with meat and dairy products.
In many human exercise studies, a dose of greater than 5 g of supplemental BCAA was used to produce the effects on muscle protein synthesis. Recent research indicates that dosages typically range from 200-300 mg of each BCAA up to 2-5 grams of each daily. However, the minimum dose to produce the beneficial effects of BCAA supplementation remains to be established. Furthermore, although leucine seems to be the most important of the three, it is not advisable to focus solely on it, since an imbalance may result. Toxic effects have not been reported thus far.