Public interest in extraordinary athletic achievement fuels the modern-day science of performance enhancement in sports. The desire to improve athletic performance in a scientific manner is a relatively recent development; at one time, the focus on maximizing human physical and mental potential centered on the importance of manual work and military service. The role of sport was inconsequential, except for its potential in improving military preparedness.105 Today, "sports doping" refers to the use of a prohibited xenobiotic to enhance athletic performance. The word doping comes from the Dutch word doop, a viscous opium juice used by the ancient Greeks.30
Controversy surrounding the systematic use of performance-enhancing xenobiotics by the participating athletes has marred many sporting events. Since the International Olympic Committee (IOC) began testing for xenobiotics during the 1968 Olympic games, prominent athletes have been sanctioned and stripped of their Olympic medals because they tested positive for banned xenobiotics. However, from a public health perspective, the use of performance-enhancing xenobiotics among athletes of all ages and abilities is a far more serious concern than the highly publicized cases involving world-class athletes. The majority of studies on the epidemiology of performance-enhancing xenobiotics have investigated androgenic anabolic steroid use. Androgenic means masculinizing and anabolic means tissue building. An anabolic process stimulates protein synthesis, promotes nitrogen deposition in lean body mass, and decreases protein breakdown.250 Studies of high school students document that 6.6% of male seniors have used anabolic steroids, and 35% of these individuals were not involved in organized athletics.32 Other studies find rates of androgenic steroid use in adolescent athletes ranging from 3% to 19%.114,127,182,246,251,250
Many unexpected deaths in certain groups of young competitors have occurred in the absence of obvious medical or traumatic cause. In some cases, the use of performance-enhancing drugs is linked to the deaths. The use of erythropoietin (EPO), introduced in Europe in 1987, may have contributed to the large number of deaths in young European endurance athletes over the subsequent few years.67,89,149,173,239 In young healthy athletes experiencing cerebrovascular events or myocardial infarction, the temporal link between the use of cocaine, ephedrine, or performance enhancers such as anabolic androgenic steroids suggests a role for these xenobiotics as precipitants of these adverse events147 (Chap. 76). Nevertheless, the leading cause of nontraumatic sudden death in young athletes is most often associated with congenital cardiac anomalies.146 In autopsy studies of athletes in the United States with sudden death, hypertrophic cardiomyopathy is the most common structural abnormality, accounting for more than one-third of the cardiac arrests, followed by coronary artery anomalies.147 Medical causes of sudden death other than cardiac causes include heat stroke (Chap. 15), sickle cell trait, and asthma.75,119,132
Performance enhancers can be classified in several ways for the purposes of study. Some categorize performance enhancers according to the expected effects. For example, some xenobiotics ...