Blood Doping and Erythropoietin (EPO) ____________________________________________________________________________________________________
Blood doping (artificially induced polysythemia) is a method that is used to enhance cardiovascular endurance by physiologically manipulating the cardio-respiratory system. Basically, the technique is designed to increase the oxygen carrying capacity of an individual’s circulatory system by infusing an extra unit of blood that often contains a high concentration of hemoglobin‌the oxygen carrying component of the red blood cell. The infused blood is obtained from either a matched donor, or from the athlete himself. For instance, the athlete usually trains in high altitudes for a specific period of time in order to elevate the hemoglobin concentration of the blood. At the end of this initial training period, approximately 500 ml of blood is taken from the donor and/or athlete and stored in a cryonics lab until the athlete is ready to compete. The blood is often taken about a month or more prior to competition. When it is time for the athlete to compete, the stored blood is infused into him. This provides a greater blood and/or oxygen supply to the tissues of his body. Lasse Viren was accused of using blood doping after he amazed everyone at the 1976 Olympics by winning the 5000 and 10000 meters back-to-back and then finishing third in the 26 mile, 385 yards marathon a few days later. Theoretically, the technique appears plausible. However, findings of studies designed to investigate whether or not blood doping is a true ergogenic aid have been equivocal. Some researchers have reported that blood doping significantly enhances cardiovascular endurance while other researchers have reported no improvement on cardio-respiratory parameters. It should be noted that most of the research in this area is methodologically weak. Specifically, studies have frequently used small samples (less than ten), used non-athletic subjects with diversified levels of cardiovascular fitness, employed inaccurate instruments to assess cardiovascular parameters and have varied in the amount of blood transfused. It appears that more and better research is necessary before the value of blood doping as an ergogenic aid can be determined. On the other hand, it should be noted that based on empirical evidence, most athletes and coaches believe that blood doping is a true ergogenic aid. Introducing additional blood into the circulatory system of a normal and healthy body can cause a variety of problems including detrimental changes in circulation, respiration and hemodynamic function. For instance, it is believed by some physiologists that adding red blood cells to the normal blood level causes the ratio of cell volume to total blood volume to increase the viscosity of the blood to a point where blood circulation will decrease significantly. Blood doping has also been said to decrease minute volume of respiration, perfusability and availability of oxygen to the tissues of the body. Well, thanks to good old Western technology, blood doping appears to be a thing of the past. Erythropoietin (EPO), a clinical drug used in the treatment of anemia is now being used as a substitute for blood doping. Erythropoietin is a glycoprotein hormone produced primarily by cells in the kidney responsible for the regulation of red blood cell production. Currently, this agent is licensed for use in the treatment of the anemia of renal failure, the anemia associated with HIV infection in zidovudine (AZT) treated patients and anemia associated with cancer chemotherapy. The dose given is based on the age, height and weight of the patient. The usual dose is 50 to 100 Units per kilogram, 23 to 45 units per pound of body weight three times a week, injected into a vein or under the skin. The generic name for the synthesized drug used as treatment is epoetin. This drug comes with a variety of brand names. In the U.S. it is called Epogen and Procrit, and in Canada, Eprex. Of course, endurance athletes use EPO to increase their red blood cell production and consequently, their capacity to supply oxygen to the tissues of their body. Common side effects include headache, increased blood pressure, vision problems, weight gain and swelling of the face, fingers, ankles, feet and lower legs. The major risk factors for EPO are heart disease and vascular damage, but mainly these risk factors are only in play when EPO is used as a performance-enhancing drug.
It can also cause the agglutination of red blood cells that can lead to strokes and heart attacks. In fact, several deaths of athletes have already been linked to the drug. It is also very expensive, which has made it somewhat cost prohibitive for most amateur athletes. Even with all that, endurance athletes such as swimmers, runners and long distance cyclists love this stuff because it works extremely well and it is almost impossible to detect. A currently manufactured device called EPO ASSAY measures the concentration of EPO in one’s urine. This ASSAY produces information on erythrocytosis and increased total red cell mass. There is an excellent chance that EPO ASSAY will be used as an EPO detection device in the upcoming Olympics.