Any artificial means of increasing the total number of blood cells in the body, other than as a legitimate medical treatment. Blood doping is on the World Anti-Doping Agency's list of prohibited methods of enhancing oxygen transfer. Despite its prohibition, it is carried out by some athletes because it can significantly increase maximal oxygen uptake (VO2 max) and therefore improve endurance. Blood doping is usually accomplished by transfusion of blood either previously donated by the individual (an autotransfusion or autologous transfusion), or by transfusion of blood of the same blood type from someone else (homologous transfusion). Typically, in autotransfusions of athletes, the blood (about 900 ml or more) is extracted 5–6 weeks before a major competition so that the body has an opportunity to replace the lost blood. The blood is frozen for storage to minimize destruction of the cells. Then the stored blood is transfused back immediately prior to the competition to boost the red cell count. In addition to contravening the ethics of medicine and sport, the procedure carries a number of risks. These include the possibility of increased blood viscosity, which may put an extra strain on the heart, the transmission of infectious diseases, kidney damage, and overload of the circulatory system. Other artificial methods enhancing the uptake, transport or delivery of oxygen are also on the World Anti-Doping Agency's Prohibited list. These methods include, but are not limited to, perfluorochemicals, efaproxiral, and modified haemoglobin products. See also erythropoietin.
Subjects: Sports and Exercise Medicine.