Human growth hormone
Human growth hormone (HGH; also called somatotrophin or somatotrophic hormone) is a naturally occurring hormone produced in the human body. It promotes physical development—particularly the growth of bone—during adolescence. It stimulates the synthesis of collagen, which is necessary for strengthening cartilage, bones, tendons and ligaments, and also stimulates the liver to produce growth factors.
In adults, HGH increases the number of red blood cells and makes more energy available by stimulating the breakdown of fat. Other effects attributed to HGH include increase in muscle mass and strength, as well as tissue-repairing (recovery). However, as HGH is often used in conjunction with other performance- and image-enhancing drugs (PIEDs) its direct role in these benefits is unproven. Still, it is quite easy to see why athletes believe it will enhance their performance.
Because HGH is a protein hormone, it is possible to manufacture large amounts of HGH using recombinant DNA technology. Like anabolic steroids, HGH has a legitimate role in medicine—specifically for people with growth hormone deficiency (GHD) or muscle weakness due to HIV—but it is also misused by athletes.
There are some health risks associated with abusing HGH. Possible side-effects from use of the substance include fluid retention and swelling (particularly of the hands and feet), fatigue, increased sweating, carpal tunnel syndrome, muscle and joint pain, and insulin resistance. High doses of HGH can also lead to changes in heart structure and function. Paradoxically, it can even reduce exercise performance—definitely not a good thing for a professional athlete!
A test for HGH involves two distinct but complementary approaches: the ‘isoforms approach’ and the ‘markers approach’. A full description of the testing method is available on the WADA website. This dual-approach test has been confirmed as robust and scientifically reliable by the Court of Arbitration for Sport.
Who has used HGH in sport?
English Rugby player Terry Newton was suspended in 2010 after testing positive for human growth hormone, and Bulgarian sprinter Inna Eftimova was banned from competition in 2012 after returning a positive HGH test.
In the United States, the BALCO scandal had an enormous impact on a number of sports, particularly Major League Baseball. The scandal consisted of a PIED ring involving HGH and other doping drugs, and implicated numerous professional pro-baseball players such as Barry Bonds and Jason Giambi.