Effect of amino acid on growth hormone release. This review analyzed the effect of amino acid supplementation on the rate of human growth hormone release. Exercising athletes require a greater daily intake of protein than sedentary individuals. The mechanism for exercise-induced hGH release has not been fully defined, but it has been suggested that resistance weight training within a specific percentage of an individual's maximum limit may promote hGH response. The magnitude of hGH release is not only guided by exercise intensity and duration, but also by fitness level and type of exercise, with intermittent exercise resulting in greater secretion than continuous exercise.
Endurance exercise elicits a greater elevation in serum growth hormone than does strength training.
No contemporary evidence supports the notion that amino acid supplementation combined with strength training augments muscle hypertrophy or functional strength over that which could be obtained by strength training alone. Work and hormone-induced muscle growth have been determined to be the result of two independent biochemical processes. Hormone-induced growth does not produce such stimulation and thus, strength does not increase. Hypertrophy in the hormone-induced growth condition only occurs because of increase in noncontractile protein. Few realize the difference in effects of these two processes.