Proteins are the building materials of your body. Your body uses small amounts of protein to make glucose during long training runs (over two hours). Each gram of protein provides four calories of energy.
Protein helps build and repair muscle and other body tissues. It also plays a key role in hormone production and immune function, as well as being a source of ATP.
Endurance athletes need upwards of one gram of protein per pound of body weight.
These foods contain proteins: Eggs, Seafood, White-Meat Poultry, Milk, Cheese, Yogurt, Beans, Pork, Soy, Lean Beef, Oats, Broccoli, Cottage Cheese, Lentils, and Peanuts.