FEATURED ARTICLE: The Key to Prevent Aging with Growth Hormone
A person's supply of growth hormone and testosterone typically decreases with age. This has led scientists to administer
either or both drugs to men as a means of combating the aging process. A similar scenario exists with women and estrogen,
a hormone that also decreases with age. The lack of estrogen is associated with the onset of degenerative diseases, such as
osteoporosis, in women.
Results of testosterone and growth-hormone supplementation are mixed. Some studies show beneficial effect if the subject
is clearly deficient in them. A highly publicized study completed a few years ago suggested that giving GH to older men restored
many lost indicators of youth. These men appeared to gain muscle and lose fat while on GH. But the flip side is that many
suffered side effects, such as water retention and carpal tunnel syndrome. In addition, all gains evaporated upon cessation
of hormone injections.
This raises a question: What would happen if you combined a known stimulus of growth-hormone secretion - exercise - with GH
injections?
Researchers recently did just that and reported their results in the Journal of Clinical Endocrinology and Metabolism
(81;421-425, 1996). They gave 18 healthy men, aged 65-82, either 0.02 milligrams of GH per kilogram of bodyweight (2.2 pounds)
or a placebo for 14 weeks. The men combined these regimens with a weight-training program that lasted 10 weeks.
Results showed that taking GH did not augment muscle growth, and that aging of muscle appears not to involve the growth
hormone/insulinlike growth factor-I (IGF-1) axis. What this means is that even if older men are deficient in growth hormone,
they can still add muscle if they lift weights regularly. Other studies have also shown that exercise-induced muscle growth is
not dependent on GH release.
Animal studies show that with continued use of GH, IGF-1 cell receptors down-regulate. This is significant because IGF-1 is
thought to be responsible for most of the anabolic effects of GH. Other studies show that initial anabolic effects of GH disappear
after five weeks of use. A similar scenario exists with anabolic steroids, although the anticatabolic effects of steroids can exist
indefinitely.
Other studies show that taking GH injections for one month stops all anabolic effects of the drug, but these effects can be
restored to full measure by completely halting GH supplementation for two weeks. Taking GH regularly in high amounts increases a
plasma protein called growth hormone-binding protein that may prevent GH from locking onto its cell receptors. Thus, taking massive
doses of GH will merely reduce any effects of the drug more rapidly.
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