L-Leucine is an essential amino acid that cannot be manufactured in the body, and is part of the three branched-chain amino acid family, which constitutes approximately 70% of the amino acids in the body.
It assists the regulation of blood-sugar levels, the growth and repair of muscle tissue, growth hormone production, energy regulation and wound healing.
During times of starvation, infection, or recovery from trauma and stress, the body mobilises L-Leucine as a source for the synthesis of blood sugar within the body ( gluconeogenesis ) to aid in the healing process.
Supplements and protein powders are often fortified with L-Leucine are used by body builders and other athletes to promote muscle recovery.
It is one of the most important amino acids for hard-training athletes as, along with Isoleucine and Valine, it is not metabolised by the liver and can directly and significantly influence muscle-protein metabolism.
L-Leucine is actually considered to be the most important BCAA for athletes, as it can affect various anabolic hormones and has been shown to have an effect on preventing protein degradation.