According to a study released on Monday, the hard to detect substances improves performance in men and women. Injections of human growth hormone can improve sprint capacity enough to turn the last place finisher in the Olympic 100 meter dash into gold medal winner. The researcher at the GARVAN Institute of Medical Research in Sydney found that there could be a 4 second improvement in 1 0 second sprint, whether it is running or sprint.

David Howman, director general of the Montreal based World Anti Doping Agency told the Los Angeles Times, “This is helpful in showing those skeptics out there who say it doesn’t help performance that they’re wrong. . . Growth hormone is produced naturally in the body and it is important for growth and metabolism. While inject able growth hormone is available for people who have growth hormone deficiency, some athletes use the drug because they believe it bulks up their muscles and improves their performance”. While Professor Ken Ho , head of the pituitary research at Garvan said in a news release, “Growth hormone recipients did not increase their muscle mass. They did, however, retain body fluid and experienced swelling and joint pain, unlike those who received salt water injections. We used lower doses of growth hormone than athletes are reported to use, and for a shorter time. We can speculate, therefore, that the drug’s effects on performance might be greater than shown in this study, and its side effects might be more serious”.

Researchers also found that growth hormone increase an athletes ability to print on a bicycle, but has no effects on fitness weight lifting or jumping.