Sunday, June 27, 1999 Published at 16:42 GMT 17:42 UK
Cycling's enemy within
EPO is injected to gives athletes a massive performance boost
The drug which has done more to damage the image of top class cycle racing than any other is the latest of many substances abused by leading athletes.
Erythropoietin (EPO) is produced naturally by the body's bone marrow to encourage the growth of red blood cells, essential for physical activity.
For the world's top athletes it was like adding high octane Formula One petrol into a normal car, giving a dramatic performance boost of 15%.
It looked like the perfect drug - undetectable and natural.
But the problem, as with any tampering with physiology, were the side effects.
Long-term consequences of EPO abuse are simply not known yet, but it is already clear that its use is like Russian roulette.
The drug literally thickens the blood, turning it into thick strawberry jam-like goo if the user is not careful.
That left them at risk of thrombosis, high blood pressure and ultimately a heart attack.
The solution was either to spend the early hours on a training bike, thinning the blood down, or taking another drug to dilute the contents of riders' arteries.
And this abuse is certainly not confined to cycling, which can at least defend itself as having introduced a check designed to restrict EPO abuse over a year before last year's Tour de France.
Other sports at risk
Suspicion has fallen on marathon runners, who need similar skills to compete at the highest level, but non-endurance sports could also be affected.
Sports governing bodies stand accused of dodging the issue when they have been asked to support research.
In 1996 it was reported that the International Olympic Committee had found a way, yet the problem for all administrators is the threat of legal action from the athlete banned because of a test which is not legally watertight.
And there is also a method developed in Canada which detects signs of unusual activity in the bone marrow, where red blood cells are manufactured.
Yet no governing body has regarded any as safe and definitive enough to use, leaving the whole world of sport at risk from athletes prepared to move the goalposts.
The fight for a permanent solution will be a long one, and who can say that by the time it is won, another wonder drug will not have come along to replace EPO?
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