Athletes know that injections of testosterone and human growth hormone can dramatically boost a man's strength, energy and stamina, and a recent study just published in the Annals of Internal Medicine provided dramatic proof.
Among the findings, the report stated:
After eight weeks, researchers found that growth hormone improved sprint capacity in men and women by an average of 3.9 percent over the placebo group — which would trim 0.4 of a second from a 10-second time in the 100-meter dash, said study lead author Dr. Kenneth Ho at St. Vincent's Hospital in Sydney, Australia. In the 2008 Olympics, the top three male finishers had times of 9.69, 9.89 and 9.91 seconds.
"This is the first demonstration that growth hormone improves performance and justifies its ban in sport," Ho said in an Associated Press report.
What does that mean for the nonathlete of a certain age? Testosterone and HGH both decline steadily with age, and bringing levels up by administering synthetic supplements can help counteract some signs of aging, including the accumulation of dreaded belly fat, which has been reported to have some correlation to heart disease, as well as other problems of aging. More and more physicians now offer such treatments.
But new techniques achieve similar results by coaxing the body to produce more of its own testosterone and HGH.
An injection of human chorionic gonadotropin, a hormone distilled from the urine of pregnant women, can stimulate the testes to secrete more testosterone.
The National Institute on Aging, along with many physicians, do not endorse the practice since little research has been done on the safety of HCG and its long-term effects, but it's not illegal.
It is, however, rather expensive, and not covered by insurance.
The disposable syringes that a man needs to inject himself with HCG two to five times a week will cost about $150 to $200 a month, according to Dr. Robert Rubin of BodyLogicMD of Tampa. Rubin provides the treatment.
That's in addition to the initial workup, which costs about $500 to $600, plus about $400 for the initial hormone testing.
But the effects are often dramatic, according to Rubin.
"A lot of men who come in realize something's wrong, but they don't know what," he said. "I've seen executives who are thinking of retiring because they've lost focus and drive. Most men don't realize the problems they can have from low testosterone, which peaks around the age of 20, and starts to decline by 1 to 3 percent a year around the age of 30."
By the age of 50 or so, HCG probably won't work very well anymore, according to Rubin, because the testes may be unable at that point to produce significantly more testosterone. In that case, Rubin may prescribe testosterone itself administered either through injection, on a patch or as a gel applied to the skin.
Supplying testosterone in this way may lower a man's sperm count, and his testes may shrink a little bit, according to Rubin.
"And since testosterone can be converted to estrogen in the body, a man's estrogen level can go up and he can get breasts and other side effects," Rubin said. "If you can stimulate the testes to produce more testosterone, it's more natural. The more natural way is the better way."
Other researchers are trying to coax the body into producing more human growth hormone.
In one experiment, nearly 400 older men and women who had fallen at least twice in the previous year, and who had lost enough grip strength to interfere with ordinary tasks such as cooking and making the bed, were divided randomly into groups to receive either a "growth hormone secretagogue," which stimulates the production of human growth hormone, or a placebo.
Those who received the GHS gained an average of 3 pounds in muscle mass and improved their ability to climb stairs and walk heel-to-toe, according to Dr. George Merriam, professor of Medicine at the University of Washington and at the VA Puget Sound Health Care System and senior author of the study.
Two types of secretagogues stimulate the body's own production of HGH, Merriam said.
One, which must be injected daily, mimics the hormone that stimulates the production of HGH. Another, which can be taken orally, mimics the action of ghrelin, a hormone that stimulates appetite.
Growth hormone has long been given to children who do not produce enough of it, thereby enabling them to achieve a normal height. However, a law prohibits giving growth hormone to adults for cosmetic or "antiaging" purposes.
Currently some physicians get around this by claiming to bring an adult's HGH back up to a "normal" level, with "normal" left open to interpretation. Giving HGH directly, however, interferes with the body's own production of the hormone.
Secretagogues, in contrast, boost the body's ability to produce HGH.
"Hormones are regulated by natural feedback loops that keep them within a controlled range, and administering growth hormone bypasses these regulatory mechanisms," Merriam said. "Giving secretagogues preserves many of the regulatory mechanisms, so giving them rather than growth hormone itself addresses the likely physiological mechanisms that cause the decline in growth hormone with aging."
However, such secretagogues, though in development, aren't available just yet, and the over-the-counter "growth hormone boosters" available in health food stores won't do much, according to Merriam.
"The ones I've seen in the U.S. are just mixtures of amino acids," he said. "Nothing that I would recommend is on the market now."
Tom Valeo writes frequently about health matters. You may write him at firstname.lastname@example.org.