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DRUGS IN SPORT To compete in the modern Olympic Games, to win gold, to stand on the rostrum as the flag is raised and the national anthem played is the dream of many. But it will come true for only a few. Only the gifted, only the dedicated, only the best will win. And maybe a few drug cheats? Modern sport is plagued by suspicions that many top athletes resort to drug-taking – doping – to enhance their performance. They use anabolic steroids, human growth hormone, erythropoietin (EPO), beta-blockers, stimulants or diuretics. While drugs such as these get a lot of publicity, they are perhaps not well understood. What do they do? What are the health risks in the short or long term? Can the drugs be detected? Here we look at three of the better known drugs in sport – anabolic steroids, human growth hormone and EPO. All are members of a family of chemicals called hormones – naturally occurring chemical messengers that regulate many of the body's functions. The main hormones are produced by glands and are transported around the body in the bloodstream. Because of their importance in the growth and development of organs and tissue, hormones are the main target in the development of performance-enhancing drugs. But, as we will see, the fact that the drugs occur naturally in the body sometimes makes detecting drug abuse difficult. Anabolic steroids Anabolic steroids are drugs that resemble testosterone, a hormone which is produced in the testes of males and, to a much lesser extent, in the ovaries of females. Testosterone is partially responsible for the developmental changes that occur during puberty and adolescence and is also involved in controlling the rates of buildup and breakdown of the main biochemical components of all tissues, including muscle. Because testosterone and related drugs affect muscle growth, raising their levels in the blood could help athletes increase muscle size and strength. Athletes who use anabolic steroids also claim that they reduce body fat and recovery time after injury. But the androgenic (masculinising) side-effects – such as increased body hair and a deepening of the voice – are not always desirable, particularly in women. To counteract these sideeffects, scientists manufacture steroids that retain their anabolic effects but have a lower androgenic effect (eg, androstenedione and nandrolone). Substances: Erythropoietin (EPO) Erythropoietin (EPO) is a peptide hormone that occurs naturally in the human body. EPO is released from the kidneys and acts on the bone marrow to stimulate red blood cell production. An increase in red blood cells improves the amount of oxygen the blood can carry to the body's muscles. It may also increase the body's capacity to buffer lactic acid. Recombinant (artificially produced) EPO has a legitimate use in the treatment of anaemia in patients with diseases such as kidney disease, HIV and some cancers. Some athletes may use recombinant EPO to improve endurance performance or to improve recovery from anaerobic exercise. Side effects Use of recombinant EPO can cause the blood to thicken excessively. The heart has to work harder to pump the thicker blood and the blood is more prone to clot. Consequently, EPO use can increase the risk of heart attack, stroke and clots in the lung. The risk is exacerbated by dehydration which often occurs during endurance exercise. EPO is prohibited both in and out of competition under the World Anti-Doping Code 2006 Prohibited List Substances: Human Growth Hormone (hGH) Human growth hormone (hGH) or somatotropin, is a glycoprotein hormone that is synthesised and secreted by cells in the anterior pituitary gland. hGH is known to act on many aspects of cellular metabolism and is also necessary for skeletal growth in humans. The major role of hGH in body growth is to stimulate the liver and other tissues to secrete insulin like growth factor (IGF-1). IGF-1 stimulates production of cartilage cells, resulting in bone growth and also plays a key role in muscle growth. A deficiency in hGH before puberty results in growth retardation and dwarfism. Excess secretion of hGH after puberty has little effect on skeletal growth but results in a disease known as acromegaly. In years past, growth hormone purified from cadaver pituitaries was used to treat children with severe growth retardation. More recently recombinant (artificial) hGH has lead to several other applications including treatment of growth disorders and cosmetic symptoms of aging. hGH may be used in sport to induce anabolic effects, reduce muscle cell breakdown and reduce body fat. Side effects One of the most common side effects of hGH abuse is acromegaly. The onset of this disorder begins with an overgrowth of bone and connective tissue which leads to a change in appearance such as a protruding jaw and eyebrow bones. Because of the role that hGH plays in stimulating IGF-1 secretion, excessive use of hGH may also lead to metabolic dysfunction, including glucose intolerance and other side effects associated with excess levels of IGF-1. Status in Sport Human growth hormone is a prohibited both in and out of competition under the the World Anti-Doping Code 2006 Prohibited List (effective from 01/01/06). Research the tests that are involved to test drug users using: Steroids: HGH: EPO: Research the methods athletes use to try to hide that they are using drugs. Steroids: HGH: EPO: