Historically, drugs used to increase the ability of an athlete to perform in a given sport included the use of stimulants to diminish the onset of fatigue or opiates to diminish the pain of exertion. Recently, abuse of ana-bolicâ€“androgenic steroids (derivatives of testosterone) has increased. They are used to increase muscle size and definition (in the case of body-building competitors) and are sometimes coabused with other growth en-hancers, such as human growth hormone. In sports in which mass, physical size, or even total strength (a func-tion of total muscle mass) is important, the abuse of an-abolic steroids provides a shortcut to attainment of the physical stature that might otherwise require much more extensive training and exercise. However, it is a misconception to believe that anabolic steroid abuse is limited to professional athletes and body builders. There is clear evidence that these drugs are abused by adult men and women who are not athletes, who are blue-collar and white-collar workers, and by male and female athletes at the college, high school, and junior high school levels.