Glutamine and citrulline for maximum metabolic fitness

glutamine and citrulline are amino acids that are crucial for metabolic fitness. Citrulline is partially produced during reactions involving glutamine. Glutamine plays an important role in the function of the immune system. Many athletes take glutamine to prevent upper respiratory tract infections and influenza. Glutamine is the most abundant amino acid in the body, but its stores can be depleted by trauma, serious illness or intense training.
Citrulline is an important amino acid involved in the formation of urea. It is a popular component in sports supplementation as it is involved in key amino acid reactions and affects blood flow by increasing nitric oxide levels. Nitric oxide is an important chemical secreted by the endothelium, the inner lining of blood vessels.
Glutamine promoteswound healing and accelerates recovery from serious illness, injury, trauma and burns. Several studies have found a link between suppressed immune function and low glutamine levels.
A study conducted at Baylor University found that glutamine is not a significant amino acid for the production of citrulline. Good dietary sources of glutamine include beef, chicken, fish, eggs, milk, dairy products, wheat, cabbage, beets, beans, spinach and parsley, while watermelon rinds are an excellent source of citrulline.
(American Journal Physiology Endocrinology Metabolism, 299: E69-E79, 2010)