L-isoleucine is an essential BCAA (branched chain amino acid). Foods which have high content of L-isoleucine include nuts and seeds, meat, legumes, eggs, peas, soy products, brown rice, and whole wheat, among others. L-isoleucine in the body is generally found in its highest concentrations in the muscles. L-isoleucine levels will be lowest right after exercise and will need to be recovered. Supplementation of L-isoleucine one hour before exercise may help aid recovery.* L-isoleucine may also help maintain endurance and promote muscle growth when taken in conjunction with exercise.** These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.