Growth hormone, arginine and exercise.
OBJECTIVE
To describe the effect of an acute bout of exercise on growth hormone responses and to discuss the effect of L-arginine supplementation on growth hormone responses.


RESULTS
Recent studies have shown that resting growth hormone responses increase with oral ingestion of L-arginine and the dose range is 5-9 g of arginine. Within this range there is a dose-dependent increase and higher doses are not well tolerated. Most studies using oral arginine have shown that arginine alone increases the resting growth hormone levels at least 100%, while exercise can increase growth hormone levels by 300-500%. The combination of oral arginine plus exercise attenuates the growth hormone response, however, and only increases growth hormone levels by around 200% compared to resting levels.


CONCLUSIONS
Exercise is a very potent stimulator of growth hormone release and there is considerable research documenting the dramatic growth hormone rise. At rest oral L-arginine ingestion will enhance the growth hormone response and the combination of arginine plus exercise increases growth hormone, but this increase may be less than seen with exercise alone. This diminished response is seen in both in both younger and older individuals.
Kanaley
Jill A
JA
Department of Exercise Science, Syracuse University, Syracuse, New York, USA. jakanale@syr.edu
D000284:Administration, Oral; D001120:Arginine / Q000008:administration & dosage / Q000494:pharmacology*; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D015444:Exercise / Q000502:physiology*; D019382:Human Growth Hormone / Q000097:blood* / Q000187:drug effects*; D006801:Humans; D018482:Muscle, Skeletal / Q000378:metabolism*
D019382:Human Growth Hormone; D001120:Arginine