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For Tour de France winner Floyd Landis, the results of his doping test mean the difference between glory and disgrace. For sports doctors, the issue may be a coldly scientific one: Can a night of drinking dramatically alter results of a steroid test? (And how accurate are these tests anyway?)
Meanwhile, fans watching from the sidelines have been left a bit confused by all the talk of testosterone ratios and what might affect them. WebMD went in search of some of the answers.
Question: What is testosterone?
Answer: Testosterone is the "male" hormone, accounting for strength and endurance. It occurs naturally in men and in smaller amounts in women. For every molecule of testosterone produced by the body, another molecule of a substance called epitestosterone, which does not enhance performance, is made.
In a normal male body, the ratio of testosterone to epitestosterone, the T/E ratio, is about 1:1. But variation can occur in individuals, and the World Anti-Doping Code has deemed 4:1 as the threshold for a positive test.
Question: What is synthetic testosterone?
Answer: This anabolic steroid is a form of testosterone usually produced from soy or yams in factories, not the human body. It can be introduced into the body by injection, with patches, or other means.
Question: What happens to the body when it is introduced?
Answer: Gary Wadler, MD, chairman of the Prohibited List and Methods Committee of the World Anti-Doping Agency (WADA), says this would be a deliberate attempt to increase muscle strength and mass, shorten recovery time from vigorous exercise, and keep muscle tissue from breaking down (catabolism) when pushed to the extreme.
Steroid Abuse
Question: How common is "doping" with anabolic steroids?
Answer: Of every 100,000 samples from athletes analyzed at 24 labs around the world for the International Olympic Committee, 1.6% come up positive -- 65% of those for anabolic steroids.
Question: Does synthetic testosterone kick right in and provide an immediate boost?
Answer: This has doctors puzzled in the Landis case. Apparently, the contender did poorly on one leg of the race, went out to drown his sorrows, and then had a miraculous recovery the next day to win. Wadler says this is not typical of how synthetic testosterone works. "Most effects surface after a few weeks," Hellman says, "not a few hours."
Question: Don't the tests tell the story?
Answer: Remember the 1:1 ratio between naturally occurring testosterone and epitestosterone? Landis apparently came up with a 4:1, or some even say 11:1, ratio in tests done after he won.
According to Hellman, adding synthetic testosterone shuts down the body's manufacture of both the natural products. So the ratio can soar as the synthetic steroid's level rockets past production of the natural epitestosterone. Landis says his test was off because he had been drinking the night before, was dehydrated, and had a lot of testosterone in his body naturally.
The Tests
Question: How accurate are the tests?
Answer: There are different levels of testing, Hellman says. "We are not being told, yet, what was done." First, there is the basic urine test. "This can be skewed by contaminants and cannot separate natural testosterone from synthetic," Hellman says. Second, there are radioimmunoassays. These are more accurate, because samples are purified, but they still cannot separate natural from synthetic. The third level, carbon isotope ratio mass spectrometry, can tell if synthetic testosterone is present. "Since most people don't live on yams and soy, this can pick out the difference between natural and synthetic," Hellman says.
"I would wonder which tests were done. There is also a chance the samples were not handled properly and could have been tampered with. Some labs are better than others. These tests are not that easy to do. You don't just pour something in a tube."
Question: Could alcohol have interfered?
Answer: Hellman says alcohol can alter tests, but perhaps not to this dramatic a degree. However, there is not a lot of scientific information on this. "I don't know too many scientists," Hellman says, "who spend time getting athletes drunk."
Question: Are new tests needed when the stakes are this high?
Answer: New techniques are being developed, Wadler says. Martial Saugy, of the Swiss Laboratory for Doping Analyses in Lausanne, has called for new testing methods and for WADA to act more speedily.
Effects of Steroid Abuse
Question: Why not take anabolic steroids? They are a substance naturally occurring in the body, after all.
Answer: The key here would be "natural." Taking anabolic steroids is a case of too much of a good thing.
Wadler reels off a list of bad side effects. Besides the well-known "'roid rage," anabolic steroids can cause your body to stop its normal production of testosterone, the testes to shrink, sperm production to drop, breast tissue to develop, and the liver to become diseased -- to name a few unpleasant effects.
"Some effects are physical, some psychological. Some wear off, some don't," Wadler says. "And some show up later, after you quit taking steroids. You think you have gotten away with it and you haven't."
Question: Back to the dramatic turnaround in Landis's performance. How could this have even occurred from a slow-acting agent?
Answer: If it's determined steroids were used, "The irony may be," Hellman says, "that even if he did apply a patch, he won because of the placebo effect. He might have thought it gave him a big advantage. So he really was that good, but lost his medal anyway."
All of this, Hellman says, will probably end up in court.
Published Aug. 4, 2006.
Star Lawrence is a medical journalist based in the Phoenix area.
SOURCES: Richard Hellman, MD, president-elect of the American Association of Clinical Endocrinologists; clinical professor of medicine at the University of Missouri, Kansas City, School of Medicine. Gary Wadler, MD, chairman, Prohibited List and Methods Committee of the World Anti-Doping Agency; spokesman, American College of Sports Medicine. Web site of World Anti-Doping Agency's U.S. arm.