Your body can only do so much with the tools that it has, so eat well. Aim for a wide variety of foods (instead of the same old thing day in and day out) from every basic food group. Try new fruits and vegetables, ethnic cuisines, and a wide range of lean proteins, including non-meat sources like tofu and legumes. All (or most) of your grains should come from whole, unrefined foods like whole-wheat breads and pasta, and brown rice. These healthy foods, especially when eaten every three to four hours, will help raise and stabilize your metabolism (and energy) to optimal levels. With fewer ups and downs, your hunger will stay in check, and you’ll have plenty of energy to start and finish a workout.