Not a jock? Find other ways to fit activity into your day: walk to school, jog up and down the stairs a couple of times before your morning shower, turn off the tube and help your parents in the garden, or take a stroll past your crush's house — anything that gets you moving. Your goal should be to work up to 60 minutes of exercise every day. But everyone has to begin somewhere. It's fine to start out by simply taking a few turns around the block after school and building up your levels of fitness gradually.
In a way, moderate-intensity physical activity is that "magic pill" a lot of people are looking for, because the health benefits go beyond keeping your waistline trim: Not only can it reduce your risk of cancer, stroke, diabetes and heart attacks, but studies have shown that physical activity can significantly improve the moods of patients with major depressive disorders.