BCAA's (L-Leucine, L-Isoleucine, L-Valine)

Consumption of BCAA (30 to 35% leucine) before or during endurance exercise may prevent or decrease the net rate of protein degradation, may improve both mental and physical performance and may have a sparing effect on muscle glycogen degradation and depletion of muscle glycogen stores.

Leucine turns on protein synthesis, which stimulates muscle hypertrophy. Even adding leucine by itself to protein assists to further stimulate muscle protein synthesis.

According to some in the industry L-isoleucine is most effective as a supplement in terms of boosting energy and increasing endurance. 

L-Valine is the dietary supplement form of the BCAA valine. It is commonly taken by weightlifters and performance athletes to support muscle and tissue repair as well as to provide them with adequate energy while performing taxing activities. 

Apart from supporting protein growth, it also discourages problematic brain cell messaging. People with liver disease and anorexia can benefit from this.