Carbohydrates

During moderate exercises, carbohydrates make up 40-50% of the energy used in the body. Carbohydrates provide more energy per unit of oxygen consumed. Because oxygen is often the limiting factor in long duration exercises, it would be beneficial for the athlete to use energy sources requiring the least amount of oxygen.

Complex Carbohydrates come from foods like spaghetti, lasagna, cereals, and other grain products. Simple Carbohydrates are found in fruits, milk, honey, and sugar. During digestion the body breaks down these carbohydrates into glucose and stores the glucose in the body's muscles as glycogen.

For sports and events that lasts for 90 minutes or longer eating a high-carbohydrate diet two or three days before the event allows the glycogen storage spaces to be filled. Eating a high-carbohydrate diet the day before the event may cause you to be sluggish and may cause stiffness in your muscles. Eating a high-carbohydrate diet consistently is not recommended though, because under these dietary conditions your body will only use carbohydrates for fuel and the not fatty acids taken from the fats. For even longer events that take around 3-4 hours, try consuming some carbohydrates during the event to insure that the glycogen stores in your muscles and livers are at its max.

An example of a high-carbohydrate diet:

Food item	Calories	Grams carbohydrate
Breakfast
8 ounces orange juice	120	28
1 cup oatmeal	132	23
1 medium banana	101	26
8 ounces low-fat milk	102	12
1 slice whole wheat toast	60	12
1 tablespoon jelly	57	15
Lunch
2-ounce slice ham	104	0
1 ounce Swiss cheese	105	1
2 slices whole wheat bread	120	25
1 leaf lettuce	1	0
1 slice tomato	3	1
8 ounces apple juice	116	30
8 ounces skim milk	85	12
2 cookies	96	14
Dinner
3 cups spaghetti	466	97
1 cup tomato sauce with mushrooms	89 5	19 1
2 tablespoons Parmesan cheese	45	0
4 slices French bread	406	78
1 slice angel food cake	161	36
1/4 cup sliced strawberries	13	3
1/2 cup ice cream	133	16
Snack
16 ounces grape juice	330	83
6 fig cookies	386	81
TOTAL	3236	613
	(75% of total calories)

(From http://www.ext.colostate.edu/PUBS/FOODNUT/09362.html)