Water, Protein and Fats

Protein and fats: Important, but not your body's top fuel choice
Protein isn't your body's food of choice for fueling exercise, but it does play a role in muscle repair and growth. Most people can easily get the protein they need from such foods as meat, dairy products and nuts, and don't need additional protein supplements.

Fat is an important, although smaller, part of your diet. Fats, as well as carbohydrates, can provide fuel for your muscles during exercise. Try to get most of your fat from unsaturated sources such as nuts, fatty fish or vegetable oils. Avoid fatty foods just before exercising, though. Fats remain in your stomach longer, causing you to feel less comfortable.

Water: Drink plenty to avoid dehydration
Your body uses the water in your blood to carry nutrients such as sugar (glucose) to cells and to remove waste products from the cells. The presence of water in your body ensures that you can safely sustain physical activity. As you exercise, your body produces heat. This heat leaves your body as you perspire, taking with it electrolytes — elements, such as potassium, calcium, sodium and chlorine. If you don't replace the fluid you lose during exercise, your heart rate increases and your temperature rises, putting you at risk of dehydration as well as compromising your workout.

To stay well hydrated during exercise, the American College of Sports Medicine recommends that you drink eight glasses of water every day and more on days when the temperature and humidity are high.

Drink at least one glass of water before and after your workout and every 10 to 15 minutes during your workout to replace fluid lost in perspiration. Avoid substituting coffee, tea or soda for water, because they often contain caffeine, which acts as a diuretic that causes your body to lose even more water.

Water is generally the best way to replace lost fluid, unless you're exercising for more than 60 minutes. In that case, sip a sports drink to help maintain your electrolyte balance and give you a bit more energy from the carbohydrates in it. The sodium in sports drinks also helps you rehydrate more quickly.