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Blood doping at the Olympic Games.

INTRODUCTION
The objective of this paper was to review our knowledge of athletes who have, are believed to have or have attempted to engage in blood doping to enhance their performance at an Olympic Games.


EVIDENCE ACQUISITION
The paper focused on the Games from Munich 1972 to London 2012 and the author had a medical role at each of the Olympics that is discussed.


EVIDENCE SYNTHESIS
The study revealed that Olympic athletes have benefitted from manipulating their blood by re-infusion of autologous or infusion of homologous blood and by administering erythropoiesis stimulating agents, notably the three generations of erythropoietins. Fifty seven athletes have been sanctioned with 12 athletes forfeiting 17 Olympic medals including 12 gold medals because of blood doping. Until 1986, the infusion of blood was not prohibited in sport but considered unethical. Erythropoietin was prohibited by the International Olympic Committee's Medical Commission in 1990.


CONCLUSIONS
There has been a change as to how Olympic athletes have enhanced performance by blood doping, commencing with blood infusion and later administering erythropoiesis stimulating agents and significant advances have occurred in detecting such misuse. Currently, the hematological component of World Anti-Doping Agency's athlete biological passport is an important but not infallible mechanism to identify athletes who cheat by blood doping.