Amino acids are fundamental to life, used by the body to build proteins. Proteins are needed to form cells and are part of the chemical structure of hormones, enzymes, neurotransmitters and antibodies. Glutamine (abbreviated Gln or Q) is one of 20 amino acids involved in the composition of proteins and has reference codons in the genetic code; it is a side chain of an amide of glutamic acid, formed by replacing the hydroxyl of glutamic acid with an aminal functional group.
This amino acid in a dietary supplement serves to keep the muscles that are exercised from losing volume.