EPO (Erythropoietin)

EPO Erythropoietin (pronounced ah-rith-ro-poy-tin, and abbreviated, EPO) is a relatively recent entry into the arsenal of endurance athletes. EPO is a protein hormone produced by the kidney. After being released into the bloodstream, it binds with receptors in the bone marrow, stimulating the production of red blood cells (erythrocytes). Medically, Erythropoietin is used to treat certain forms of anemia (e.g., due to chronic kidney failure). Logically, since Erythropoietin accelerates erythrocyte production, it also increases oxygen-carrying capacity. This fact did not long escape the notice of the athletic community or, for that matter, Lance Armstrong.

Blood doping artificially increases the number of red blood cells in the body to improve athletic performance. In the past, this was accomplished by blood transfusion. The athlete would donate a unit of blood into storage, and then three weeks later, after the body had completely replaced the blood loss, transfuse the team back into the body. This would occur just before a big race, effectively giving the athlete an extra unit of blood. This enables performance improvements in endurance sports because of the excess oxygen-carrying capacity. Administering EPO for five days before a race? Or endurance event achieves the same effect as the blood transfusion; however, increase the dose and the period of the time administered by a factor of 4, and you have effectively increased your blood oxygen capacity by 30% on