Effects of hGH a cloudy issue, experts say

No lab evidence showing substance helps strengthen athletes

By Childs Walker | Sun Reporter

September 11, 2007

Jay Gibbons missed 65 games because of injuries in 2004, when he allegedly bought testosterone and growth hormone. (Sun photo by Gene Sweeney Jr. / May 8, 2007)

Sports fans and commentators speak of human growth hormone as a magical substance that offers the same benefits as anabolic steroids but cannot be detected in urine tests.

So when a player is linked to hGH, as Orioles outfielder Jay Gibbons was by an SI.com report, many presume the player was desperate to bulk up and power baseballs into the stands.

The scientific community doesn't uniformly agree, however, that hGH would help an athlete do so. Several studies of senior patients have found that hGH helps build lean muscle mass but does not increase muscle strength. This conclusion might not transfer perfectly to high-level athletes in their physical primes. But there is no laboratory-based evidence that hGH would help strengthen these elite performers, several researchers said.

"What athletes are doing is probably unlike anything we see in a clinical setting, so we don't know what it does," said Dr. Mary Lee Vance, a professor of internal medicine at the University of Virginia who wrote a 2003 study of growth hormone. "But the point is that none of our studies of aging populations have demonstrated measurable benefits other than to body composition."

Vance said it's possible that hGH, used in conjunction with high-intensity workouts, builds strength. But unlike with anabolic steroids, those benefits are perceived, not proven. Steroid use increases muscle mass disproportionately to overall body size. Growth hormone increases overall thickness, from muscle to bone to hair.

"If you take steroids and work out, you will get bigger and stronger," said Will Carroll, who writes about sports medicine issues and studied performance-enhancing drugs for his 2005 book The Juice. "If you take hGH and work out, there's no real clear evidence that you'll get stronger than you would have if you had just worked out."

That also was the conclusion reached by a 2004 survey of research on the subject in the American Journal of Sports Medicine.

Some athletes, including St. Louis Cardinals outfielder Rick Ankiel and New England Patriots safety Rodney Harrison, have said they turned to growth hormone to recover from injuries.

"That's the only reason guys take it," said former Orioles first baseman David Segui, who has said he took hGH on advice from his doctor. "People think guys are living on it, and that's not true. People don't want to hear this, but you don't get bigger and stronger off it. You don't get that big steroid look, that bulky look."

Perception vs. reality

Vance questioned athletes' belief in the substance's healing power.

"I think the key word is perception," Vance said, "because there's no evidence at all that it helps anyone recover from injuries."

Dr. Bill Howard, founder of the sports medicine clinic at Union Memorial Hospital, isn't so sure. He noted research on animals suggesting that growth hormone can help heal micro-injuries to the muscles. Such effects could help an athlete attempting to rehabilitate an injury, he said.

"It's the trendy, untestable drug, so that perception is a big reason why guys are going to take it," he said. "But I don't think their belief in it is unfounded. I think it does help you continue with hard workouts when it might be harder to do so otherwise."

Howard said hGH probably isn't as effective a strength builder as anabolic steroids.

Dr. Gary Wadler, a professor at New York University and member of the committee that determines banned substances for the World Anti-Doping Agency, agreed. But he suspects many athletes use it in tandem with low doses of testosterone, which could strengthen muscles made larger by hGH. SI.com reported that Gibbons received testosterone, as well.

"I think that many dopers are using several substances in combination," Wadler said. "And the science suggests that can be effective."

The negative effects of hGH are better established, researchers agreed.

Heavy users might quickly experience carpal tunnel swelling in the hands, and long-term use can lead to heart disease, diabetes and debilitating joint swelling, Vance said.

Gibbons is the latest athlete alleged to have received prescription performance-enhancing drugs from Orlando, Fla.-based Signature Pharmacy. The names have trickled out since February, when New York investigators raided the pharmacy in connection with an Albany County district attorney's investigation of an Internet steroid ring.