What are BCAA’s?

BCAA’s have been popular in the body building fraternity for decades but in recent years have become increasingly popular amongst the wider athletic population The three branched-chain amino acids (leucine, isoleucine and valine) are also essential amino acids as they cannot be synthesised by the body and must be obtained from dietary sources. BCAA’s have a unique characteristic in that they can be metabolised in skeletal muscle (other essential amino acids are metabolised via the liver).

BCAA’s and performance

BCAA’s have been proposed to benefit performance in several ways including as a stimulant for muscle protein synthesis (through leucine). BCAAs may also prevent muscle protein breakdown and reduce markers of exercise induced muscle damage. There is also some research suggesting that BCCA’s have the potential to act as a fuel source for muscles during exercise, although the research surrounding this is inconclusive. Lastly, BCAA’s may interfere with the transport of tryptophan into the brain, reducing the synthesis of serotonin thereby reducing feelings of fatigue.

Athletes that may benefit from BCAA supplementation

Questions still remain regarding the benefit of BCAA supplementation over whole protein supplementation – food or protein powders – or carbohydrate intake (from a fuelling and fatigue perspective). However, athletes on a tight energy budget may be a good candidate for supplementation with BCAA’s as they can help to promote muscle protein synthesis and minimise muscle protein breakdown without a substantial calorie load.

Recommended dosing strategy

Research protocols have used a wide range of dosing strategies however, to get the maximal benefits for muscle protein synthesis and recovery via leucine, a dose of BCAA that provides ~2-3g leucine (this can vary depending on the brand) is suggested.

Potential side effects

To date, there have been no adverse side effects reported for BCAAs. One research paper found no toxic effects from daily doses of 1.25g/kg body weight over 12 months.

Summary

The incorporation of BCAA supplementation into an athlete’s nutrition plan should be considered on an individual basis. Working with an Accredited Sports Dietitian will help to ensure that the most appropriate dosing strategy and best results are achieved.

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