I am constantly encouraging patients to exercise.  Usually, the motivation is physical health -- the patient's weight, or blood pressure, or cholesterol, or sugar is too high and exercise is the healthiest way to normalize it.  But I'm increasingly impressed by the ability of exercise to improve mental health.  Patients tell me all the time that their mood is better, their anxiety lower, and their thinking sharper when they exercise than when they don't. A recent study adds evidence to that bel...