Glutamine is an amino acid that can be found in eggs, meat, whey protein and casein protein.(29) Out of all the amino acids in the body glutamine is the most abundant. When the body is going through intense exercise glutamine levels in muscle and blood begin to drop. (30) Studies show that this could take up to 6 days to replenish glutamine levels. Glutamine is especially important after exercising as it is considered anti-catabolic so it helps minimize muscle breakdown. Glutamine has indicated positive effects on human growth hormone secretion which can aid in body fat and building muscles.(31)(32) When you exercise you immune system take a hit. Glutamine is preferred by cells for helping as an energy source for the immune system and intestines.(29)