In a comprehensive review of HGH used as a PED (performance enhancing drug) a team at Stanford says that current evidence suggests no anabolic effect for the hormone. (although this paper is called a study, it isn't; it is a review or meta-analysis of past papers)
Athletes who take human growth hormone may not be getting the boost they expected. While growth hormone adds some muscle, it doesn't appear to improve strength or exercise capacity, according to a review of studies that tested the hormone in mostly athletic young men.
"It doesn't look like it helps and there's a hint of evidence it may worsen athletic performance," said Dr. Hau Liu, of Santa Clara Valley Medical Center in San Jose, Calif., who was lead author of the review.
Growth hormone, or HGH, is among the performance enhancers baseball stars Roger Clemens and Andy Pettitte were accused of taking in the blockbuster Mitchell Report. Clemens denies using the hormone, while Pettitte admits using it.
Will there be new studies of HGH as a PED? Maybe, maybe not.
But the new research has some limitations and sheds no light on long-term use of HGH. The scientists note their analysis included few studies that measured performance. The tests also probably don't reflect the dose and frequency practiced by athletes illegally using the hormone. Experiments like that aren't likely to be conducted.
"It's dangerous, unethical and it's never going to be done," said Dr. Gary I. Wadler, a member of the World Anti-Doping Agency and a spokesman for the American College of Sports Medicine.
There were significant differences noted with HGH, in the analysis. Lean body mass increased in the HGH subjects. Strength (measured in the studies) did not increase in the HGH subjects. However side effects became more prominent with HGH use -- edema (tissue swelling) and and joint aches (like carpel tunnel syndrome).
As we pointed out in the Huffington Post, HGH by itself may not be anabolic. There is evidence that the hormone is synergistic with anabolic steroids (or insulin or T4), which means that the effects of these hormones add to each other. Further, we don't know the effects of the drugs on the most genetically gifted athletes - professionals.
However, a study is a study. HGH by itself in these doses used in young healthy men does not appear to be an impressive anabolic drug.