I’m sure that most of us can remember when the American Medical Association condemned the idea of weight training. To most doctors, not so long ago, anyone who trained with weights was thought to be a total lunatic. Today, with close to twenty-five million members enrolled in health clubs in the United States, the fitness industry is a mega-billion dollar business, and the attitude of the A.M.A. has been shifted into reverse. They now talk of nothing but positive benefits from weight training.