L Leucine is an essential amino acid that is broken down in to fat structures. As an essential amino acid it cannot be made by the human body and, therefore, must be consumed through food such as nuts, brown rice and whole wheat bread products or dietary supplements. In total, L Leucine is around eight percent of the total amino acid count in your body’s protein structures. It is also the fourth most concentrated amino acid in your tissue. As one of the three essential BCAAs, L Leucine is essential to your basic health. The primary athletic functions of L Leucine are: Helps preserve lean tissue. Supplies your body with energy when under stress (i.e. when performing athletic activity). Preserves muscle glycogen (glucose which is stored in the muscle tissue used to power your movements).Maintains nitrogen balance. Enhances mental clarity when performing intense physical exercise. In a nutshell the effects of L Leucine in the diet are profound. It is the strongest of the BCAAs and is also what is known as a limiting nutrient . This means you must have enough L -Leucine in proportion to other amino acids in order for your body to make full use of what you eat! If you don’t have enough L Leucine in your diet your body will not be able to make use of the protein that you give it, regardless of how much protein you consume. More importantly unless you have enough L Leucine in your diet the money you spend on quality food and supplements could be wasted.