sports medicine, branch of medicine concerned with physical fitness and with the treatment and prevention of injuries and other disorders related to sports. Knee, leg, back, and shoulder injuries; stiffness and pain in joints; tendinitis; "tennis elbow" ; and dehydration are some common conditions that may be involved. Treatment and prevention include exercise programs for increasing strength, flexibility, and endurance; physical therapy; fitness tests; advice concerning nutrition and fluid replacement; and use of protective equipment. Surgery may be needed to treat some injuries. Sports medicine is also concerned with the abuse of so-called performance-enhancing drugs, such as anabolic steroids. The specialty was initially practiced primarily by physicians associated with professional sports teams, but with increased interest in amateur sports and physical fitness programs in the 1970s and 1980s, it grew rapidly.