Compulsive exercise (also called obligatory exercise and anorexia athletica) is best defined by an exercise addict's frame of mind: He or she no longer chooses to exercise but feels compelled to do so and struggles with guilt and anxiety if he or she doesn't work out. Injury, illness, an outing with friends, bad weather — none of these will deter those who compulsively exercise. In a sense, exercising takes over a compulsive exerciser's life because he or she plans life around it.