Fats are the most concentrated source of food energy available. Because of this fats are used to store excess energy. The American Heart Association has stated that thirty to thirty-five percent of all calories should come from fat, no more. An excess of fat may causes many difficulties for an athlete. Added weight and decreased mobility are just the start.
Carbohydrates are the most efficient source of energy for an athlete.
Starches and sugars are the most common form. Since carbohydrates are the primary source of energy and are not as easily stored as fats, a normal man has only enough in his bloodstream for half a day of light activity. Carbohydrates from cereal grain products, such as pasta and bread, should total almost fifty percent of an athletes calories in a day. Proteins are components in all body tissues and are used in growth and repair. Proteins are also present in enzymes, hormones, plasma, and antibodies.