Wednesday, January 31, 2007

Fats

Saturated fats come in foods from animals (i.e., meats, eggs, milk, cheese, etc.) and unsaturated fats in some vegetable products (i.e., corn oil). Fats should provide no more than about 20-30 percent of daily calories. Your body needs small amounts of fat for certain critical functions and as an alternative energy source to glucose. But eating too much fat is associated with heart disease, some cancers and other major problems, and probably means you don't get enough carbohydrates. How your body uses fat for energy depends upon the intensity and duration of exercise:
When you rest or exercise at low to moderate intensity, fat is the primary fuel source.
As you increase exercise intensity, your body uses more carbohydrates for fuel.
If your body uses up its glycogen supply and you keep exercising, your body will burn fat for energy, decreasing exercise intensity.