Glutamine is the most abundant amino acid in the body, comprising more than 60% of the free amino acid pool in skeletal muscle, and greater than 20% of total circulating amino acids. During stressful situations (i.e. heavy resistive weight training) the body can lose a large amount of glutamine. A loss of glutamine during exercise may be a signal for protein catabolism (muscle breakdown). Glutamine supplementation has been shown to prevent the loss of body mass through the positive role glutamine plays in protein synthesis and its action as a potent anabolic agent. When muscle glutamine levels are restored in a positive nitrogen balance, muscle synthesis can return to a normal rate.