L-Glutamine is the most abundant free-form amino acid in the bloodstream, with muscle containing the greatest concentration of glutamine in the body. Vigorous exercise depletes muscle L-Glutamine storage levels which can lead to catabolism (muscle breakdown). When the body is under stress, L-Glutamine becomes an essential amino acid. L-Glutamine also is intended to provide nutritive support for healthy protein synthesis. Natural Sport L-Glutamine powder is tasteless, odorless and mixes easily in water and other beverages. Also try our L-Glutamine Capsules.