Isoleucine is an amino acid that is best known for its ability to increase endurance and help heal and repair muscle tissue and encourage clotting at the site of injury. This amino acid is especially important to serious athletes and body builders because its primary function in the body is to boost energy and help the body recover from strenuous physical activity.
Isoleucine is a branched-chain amino acid (BCAA). There are three branched-chain amino acids
in the body, isoleucine, valine, and leucine, and all of them help promote muscle recovery after exercise. Isoleucine is actually broken down for energy within the muscle tissue. Is also keeps energy levels stable by helping to regulate blood sugar; a deficiency of isoleucine
produces symptoms similar to those of hypoglycemia, and may include headaches, dizziness, fatigue, depression, confusion, and irritability.
Isoleucine is an essential acid, which means that it cannot be manufactured in the body and must be obtained through dietary sources. Good sources of isoleucine include high-protein foods, such as nuts, seeds, meat, eggs, fish, lentils, peas, and soy protein. People that exercise a lot or that have a low-protein diet should consider supplementation. Isoleucine is also available in stand-alone supplemental form, but should always be taken together with the other two branched-chain amino acids, leucine and valine. The ideal balance is 2 milligrams of leucine
for each 1 milligram of isoleucine. Combination supplements that provide all three of the BCAAs may be more convenient.
People with impaired liver or kidney function should not take isoleucine without first consulting a physician, as large doses of amino acids may aggravate these conditions.