Since at least the early 1980s -- years before endocrinologists grasped human growth hormone's potent anabolic properties -- athletes have been abusing HGH. But a new anti-doping test, which will make its sports debut at the London Olympics, should, for the first time, have cheating athletes thinking twice about using synthetic growth hormone.
"The [HGH] biomarker test is in place," said David Howman, director general of the World Anti-Doping Agency. "It was approved only a matter of weeks ago."
Though this is the inaugural use of the test, to call it "new" is a bit misleading. The HGH biomarker test was already being developed in the late 1990s, and the goal of the scientists working on it was to have it in place for the Sydney Olympics in 2000. The test does not detect HGH directly, but rather looks for an unnatural increase in two markers -- insulin like growth factor 1 (IGF-1) and another substance (called P3NP) that is produced when bone or collagen is formed -- that occurs after injection of HGH.
HGH testing has been used at each Olympics since 2004, but that was the HGH "isoform" test. Natural HGH in the body comes in two different weights -- or isoforms -- but synthetic HGH comes in only one weight, so an athlete who injects synthetic HGH upsets the ratio of the two different weights in the body, and the isoform test looks for the unnatural ratio. The trouble was that the body corrects the ratio so quickly that cheaters could be caught only within a day or two of taking growth hormone. There have been only eight positive tests worldwide with the isoform test, and not one in the Olympics. The biomarker test has a detection window of at least a week, and possibly two or three.
"It's a terrific day for anti-doping when you can put a test like this in place," said Larry Bowers, chief science officer for the U.S. Anti-Doping Agency.
The Olympic news reverberated in other parts of the sports world as well. NFL spokesman Greg Aiello said the league has been closely monitoring the biomarker test, and that "we look forward to reviewing the Olympic experience to assess how the test can be used in the NFL." (Since the NFL and the players' union agreed during last year's collective bargaining to implement HGH testing, the sides have been at an impasse about the scientific validity of the isoform test, and so testing never started.)
Scientists actually showed that the biomarker test worked before Sydney, but questions remained that delayed implementation. For example: In 2004, at USADA's annual science symposium, researchers asked whether one of the markers -- the one that increases when bone is produced -- could spike if someone has a slightly broken bone. If so, then an athlete with a subtle fracture that he or she is not aware of could trigger a positive test. Several years of research later, it was confirmed that a slight break would not cause a positive test.
"It's just been a long road," Bowers said. "As a general statement, it's harder to differentiate somebody who is using something that is also produced naturally [like HGH]."
And because levels of the two biomarkers decline naturally as people get older, age-graded standards have to be used to determine a positive test among Olympians, who range from 15-year-old U.S. swimmer Katie Ledecky to 71-year-old Japanese equestrian Hiroshi Hoketsu.
Still, as WADA president John Fahey said in London, "there's no such thing as a magic bullet in anti-doping," and that holds true for the biomarker test. In some people, biomarkers simply return to normal levels faster than in other people. And, in scientific articles, Peter H. Sonsken, the endocrinologist who led the initial development of the test before Sydney, has written that because women's bodies do not respond as dramatically to injections of HGH, "the actual sensitivity of the test in detecting GH abuse in women is much lower."
WADA officials in London also suggested that athletes will try to beat the test by "micro-dosing" -- as they have with other anti-doping tests -- which is taking frequent but small amounts of a drug in order to get some effect but still avoid triggering a positive test.
"The question is always, If you take a small amount, are you really getting a benefit?" Bowers said. "If you take such a low dose that it doesn't have an effect on your body, that's the only way you could beat the [biomarker] test."
The London Olympics will be "the most tested Games in Olympic history," WADA's Fahey said. One-hundred and fifty anti-doping scientists will analyze more than 6,000 tests throughout the Olympics and Paralympics, and half of all athletes -- including every medal winner -- will be tested. Additionally, and again for the first time, certain Olympic sports will use the biological passport approach to anti-doping, in which an athlete's blood profile is monitored over time to look for unnatural fluctuations. Cycling started using the biological passport in 2008, and rider performances in mountain stages of the Tour de France subsequently declined.
The IAAF, the governing body for track and field, started using the biological passport in 2010, and announced this month that six athletes were suspended before the London Games for positive tests from the biological passport program. In London, the biological passport program will be used in six sports: cycling, modern pentathlon, rowing, swimming, track and field, and triathlon.
As a final level of deterrent, athletes' samples will be stored for eight years, so that they may be retested as anti-doping technology improves. After the 2008 Beijing Olympics, the IOC retested a number of samples for the blood-boosting drug CERA, which had been commercially available for only months before the Games. Nonetheless, five athletes were caught upon retesting, including Bahrain's 1500-meter gold medalist, Rashid Ramzi.
In the six months leading up to the London Olympics, 107 athletes in Olympic sports worldwide received sanctions for drug offenses that barred them from potentially competing in these Games. Said Fahey, "I'm pleased to say that they are not here with us in London."