THE LOWDOWN ON LEUCINE
Leucine is an essential amino acid, meaning it cannot be made by the body, and must be acquired through food or dietary supplements. Leucine is classified as a branched-chain amino acid (BCAA).

LEUCINE ALONE
By itself, Leucine can stimulate muscle protein synthesis, the process responsible for muscle growth and recovery.  Therefore it is often referred to as the “main” amino acid.

Leucine is thought to be the most effective BCAA for preventing the body’s burning of muscle stores for energy during intense workouts because it is converted to glucose more quickly than isoleucine and valine.

L-Leucine stimulates muscle protein synthesis and may be the major fuel involved in anabolic (tissue building) reactions. This makes it especially important for body builders and other athletes in sports that demand explosive strength.

HOW MUCH LEUCINE TO USE
Supplementation with at least 2 grams of daily Leucine has been shown to decrease muscle soreness, lessen recovery time between workouts, and increase lean muscle mass.


Source: http://blog.nutrabio.com/2016/05/04/the-lowdown-on-leucine/