Blood doping is the practice of increasing the number of red blood cells in the body to improve athletic performance. Red blood cells carry oxygen from the lungs to the muscles and other tissues of the body. Athletes require large amounts of oxygen during the physical exertion of endurance sports, such as bicycling or long distance running. Blood doping increases the body’s oxygen-carrying capacity, allowing athletes to train and compete with improved endurance and less fatigue.
Blood doping is illegal in sports because it gives some individuals an unfair advantage. In addition, increasing the number of red blood cells thickens the blood, which can cause heart attacks or strokes, and possibly death. Since the late 1980’s, the deaths of at least 18 cyclists have been linked to blood doping.
In the past, blood doping was done by transfusing extra red blood cells into the body. An athlete would remove 1 to 3 pints (0.5 to 1.5 liters) of his or her own blood several weeks or months before a major competition. It would take about one month for the body to replace the lost blood. In a laboratory, technicians separated the red blood cells and froze them for storage. The blood cells were then thawed and reinfused a few days before the competition.
Today, a more common method of blood doping involves injecting synthetic forms of a substance called erythropoietin << ih `rihth` roh POY uh tihn >>, also known as EPO. EPO is a naturally occurring hormone that stimulates the body into producing extra red blood cells. Doctors originally developed synthetic forms of EPO to treat severe anemia, but some athletes use it to increase their red blood cell count without a transfusion. The performance-enhancing effects of EPO can last for several weeks.
Blood doping is difficult to detect because the substances used are normally found within the human body. One detection method is to monitor an athlete’s hematocrit << HEHM uh toh kriht or HEE muh toh kriht >>, the ratio of red blood cells to total blood volume in a sample. Females have an average hematocrit of about 38 percent, while males average about 42 percent. A hematocrit over 55 percent may indicate blood doping. Athletes who live and train at high altitudes, however, also have elevated hematocrit values. The lower oxygen content of the air at high altitudes stimulates the body to manufacture more red blood cells.
In August 2000, the International Olympic Committee announced that a reliable method of testing for blood doping with EPO had been developed, and they began using it in the 2000 Summer Olympics. The test involves analyzing both a blood sample and a urine sample from athletes. Both samples must test positive in order for an athlete to be disqualified from competition.
The term doping is also used to describe the use, for the sole purpose of improving athletic performance, of any substance banned by the International Olympic Committee (IOC). These substances, often called ergogenic << `UR` guh JEHN ihk >> aids, include stimulants, such as amphetamines and caffeine; narcotics (painkillers); anabolic (muscle-building) agents, such as steroids; diuretics (substances that rid the body of water); and a variety of hormones, such as human growth hormone. The IOC may permit other substances, such as alcohol and certain anesthetics, for medical reasons.
See also Doping; Drug misuse; Human growth hormone; Olympic Games (Charges of steroid use).
