Growth
Hormones for development are released by the pituitary gland in the brain. It is responsible for enhancing muscles, burning fats and immune system maintenance.
Ornithine
This amino acid is derived from arginine. Large quantities have successfully raised growth hormone levels in some studies. Bucci, et al, studied the the effect of 40, 100 and 170 mg/kg of L-ornithine HCl on 12 bodybuilders. A percentage of twenty-five of the subjects experienced significant increases in serum growth hormone levels at the two lower doses. In the other hand, half the subjects illustrated an increase at the highest dose.
Arginine
Investigated in numerous studies with conflicting results, this is one of the amino acids that promote growth. Take for example, in one study, 6 subjects were given 6 grams of arginine. They all experienced a 100% increase in plasma levels without any growth hormone release. Other researchers administered it to 12 young and 5 elderly non-obese adults. All of whom had a body mass of less than 30. The subjects participated in three trials: resistive weight-lifting exercise with no placebo, 5 grams of arginine supplementation prior to exercise and 5 grams of oral L-arginine only.
Lysine
Lysine may work to release growth hormone. In a study of 15 healthy male subjects, there was a separate consumption of lysine as single nutrients did not significantly increase growth hormone compared to the baseline. In another study of normal young males, oral administration of 1,200 milligrams of L-lysine did not raise serum growth hormone levels.
Glycine
Glycine is contained in gelatin protein and is an important component of collagen. Although much of the early research revolved around its ability to increase strength in athletes, more recent studies have documented that it can indeed raise growth hormone levels in humans. As a matter of fact, researchers have concluded that the explanation why it has been found to increase muscle strength in many studies may be the result of its boosting capabilities.
Glutamine
An abundant protein block-builder, Glutamine is the most copious in human muscle and plasma. It directly regulates both the production and wearing-down of protein and immune cell activity. When about nine healthy subjects consumed two grams of oral glutamine 45 minutes after a light breakfast, there were eight out of the nine that subjects experienced elevated plasma growth hormone within 90 minutes. These findings demonstrate, the study authors wrote, that a surprisingly small oral glutamine load is capable of elevating hormones for development.
