It was quite a scandal. One day before the 2006 Tour de France was due to start, Jan Ullrich of Germany, Ivan Basso of Italy, and 11 other cyclists were suspended by their teams and prohibited from competing. Prior to the suspension, these heavy favorites seemed poised to contend for the trophy. What happened?
A Spanish investigation team linked the suspended cyclists to a blood doping ring in Madrid. Blood doping is a prohibited and potentially risky technique that enables your blood to carry more oxygen. It begins like a blood donation. The athlete “donates” a pint or two of his or her own blood. This blood is placed in a tube in a centrifuge, where it spins around at high speeds, like the spin cycle of a washing machine. The red blood cells—which carry oxygen—are forced to the bottom of the tube. The liquid part of the blood is drawn off from the top of the tube and re-injected into the athlete. The blood cells are stored, perhaps frozen. As with any case of blood donation, the athlete makes more red blood cells to replace the ones taken out, and the red blood cell level soon returns to normal. A day or so before the competition, the “doping” occurs. The stored red blood cells are re-injected into the athlete. These additional red blood cells allow the blood to carry more oxygen.
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Blood doping is prohibited by all major sports federations, and it is illegal in many countries. But Ullrich and Basso were not the last cyclists or athletes to be caught up in a doping scandal. In fact, in October 2012, Lance Armstrong was stripped of all seven of his Tour de France wins after evidence came to light in a U.S. Anti-Doping Agency report that he had used performance enhancing drugs and engaged in blood doping. In a 2013 interview with Oprah Winfrey, Lance admitted to blood doping and use of other performance-enhancing substances in all seven of his Tour de France wins. He also said that he did not believe it would have been possible for him to win all seven times if he had not engaged in doping.
These scandals raise several questions. First, why would front-running athletes risk their careers by doping? Second, and more relevant biologically, why would they consider blood doping to be necessary? Are there limits to the amount of oxygen our circulatory and respiratory systems can provide, limits that are tested by the grueling mountain climbs of the Tour de France? Some facts will help us answer these questions.