The BCAA supplement is mainly used for muscle growth, muscle replenishment and anti- catabolism i.e. reduce muscle breakdown. The main component in this is Leucine, which is one of the 3 BCAAs, the others being isoleucine and valine. Leucine is key to muscle protein synthesis (muscle growth), whilst isoleucine encourages the uptake of glucose into the cell, a process that is key to energy and the reduction of fatigue.
By using BCAA supplements before and during exercise you reduce the risk of a serum decline in leucine, isoleucine and valine, which consequently triggers an influx of the feel good hormone tryptophan into the brain. The problem with too much tryptophan in the brain is a secondary influx of serotonin… and serotonin leads to FATIGUE!
Keep your BCAAs topped up to reduce the onset of fatigue when exercising.
Examine.com, (2015). Branched Chain Amino Acids. Retrieved 15th June, 2015, from http://examine.com/supplements/Branched+Chain+Amino+Acids/