Glutamine is one of the most abundant of all of the 20 amino acids, making up over 60% of all skeletal muscle tissue in the body. It can be found in even higher concentrations in more vital organs such as the kidney, liver, heart, and brain. Glutamine is by far the most important of all of the amino acids when it comes to metabolism. It is the main source of fuel used by cells to complete the process of transferring fats, sugars and more into usable energy that the body can store for later. This is because Glutamine can be stored in the body and later converted into glucose, one of the chief energy providers for the body. This is what makes this supplement such an attractive option for high endurance athletes with strict training regimens. It is also used to help the body more effectively burn fat while adding on to overall muscle mass.