From the Manufacturer:
"Arginine has several important functions. It is essential to the metabolism of ammonia that is generated from protein breakdown. It is also needed to transport the nitrogen used in muscle metabolism.
Arginine is one of the body-building amino acids and also influences several hormone functions. L-arginine has been shown to stimulate the pituitary gland to produce and secrete human growth hormone in young males, at a dose of more than 3 grams daily."