L-Isoleucine is concentrated in muscle tissue in humans and has a range of functions including regulating blood sugar and energy levels, assisting wound healing, stimulating immune function, promoting secretion of several hormones, and Haemoglobin production. It may also help to prevent the breakdown of muscle during exercise, and so enhance recovery.

*Amino acids can occur in L and D forms, but only L Amino Acids are manufactured in cells and incorporated into proteins.