The Role of Carbohydrates, Fat, and Protein in Exercise

To be able to exercise your body needs carbohydrate, fat and protein!

The two main sources of exercise energy:
- Sugar stores from your liver and muscles.
- Fat stores from your muscles and fatty tissue.

Common misconceptions:
- Myth: Vitamins give you energy.
- Fact: Energy comes from carbohydrates, protein and fat in the diet.

- Myth: Your muscles will become larger with lots of protein in your diet.
- Fact: If you consume excessive amounts of protein and limit carbohydrates, the body must use protein for energy; therefore, no additional muscle is built and excess protein will then be stored as fat in the muscle.

- Myth: The harder you exercise the more fat you burn.
- Fact: More fat is burned during periods greater than 20 minutes of light to moderate exercise, such as a 45 minute brisk walk.

- Myth: If you eat during exercise you will get sick.
- Fact: Carbohydrate, such as a drink of Gatorade, provides fuel to working muscles when exercising longer than 60 minutes.

What role do carbohydrate, fat and protein play in exercise?

- Carbohydrate:

• Is the preferred source of energy during high intensity exercise, such as a step aerobics, spin class or weight lifting.
• Provides the quickest energy for the body.
• Is required to burn fat--without it, you can't burn fat.

- Fat:

• Becomes the preferred source of energy in light to moderate exercise after 20 minutes of activity, such as a brisk bike ride or walk.

- Protein:

• The body uses protein after exercise for muscle repair and growth.
• The body will use small amounts of protein for fuel during some endurance sports such as soccer and cross-country.

Use the following basic guidelines to incorporate all three nutrients into each meal:

• Carbohydrates: ½ or more of the food on your plate should come from these foods: fruits, grains, vegetables, pastas, and milk.
• Protein: 3-4 oz from these foods: dairy products, meat, poultry, fish, nuts, seeds and eggs. 3-4 is about the size of the palm of your hand or a mayonnaise jar lid.
• Fat: about 2-3 tsp from these foods: oils, margarine, salad dressing, mayonnaise and butter.
  Don't forget that some foods already contain fat naturally such as meat and diary foods or added fats such as seasoning.