L-Arginine is a conditionally essential amino acid, meaning that under normal circumstances it can be synthesized by the human body to cover its needs. In case of poor nutrition or heavy physical exertion, the biosynthetic pathway may not produce sufficient quantities of Arginine and some must be consumed from the diet or from supplements. Being the only precursor of Nitric Oxide (NO) and important precursor of Creatine, Arginine supplementation is a general practice among athletes, bodybuilders. Taking high dose capsules is the easiest way to cover an increased demand for Arginine.