Fast-digesting carbs are effective after a workout, to help replenish your muscles' depleted glycogen stores, or before a workout, if you need a quick boost of energy but don't have time for a meal. Also known as high glycemic index carbs, fast-digesting carbs come in several forms, which include natural, whole foods, and processed or packaged foods. The glycemic index of a food indicates how quickly it increases your blood sugar levels after you eat it. High glycemic index foods tend to spike your blood sugar very quickly, which is why they give you such an energy boost.
Go With the Grain
White bread and white rice are both good sources of fast-digesting carbs. While their whole-grain counterparts have much lower GI profiles, these two options will give you a quick boost of energy right away. Half a cup of steamed white rice has 103 calories and 22 grams of carbohydrate. One gram of carbohydrate contains four calories, so 88 of those calories come from the carb content of the rice. One slice of white bread has 74 calories and 14 grams of carbs, meaning that 56 of those calories come from the carb count.
Eat Your Veggies
Fruit and certain type of vegetables contain fast-digesting carbs. Among the best high glycemic index fruits are bananas, grapes, watermelon, dates and peaches. Steer clear of apples, grapefruit, pear and prunes when you are looking for a quick energy fix, as these are all slow-release carbs. High glycemic index vegetables include green peas, parsnips, white potato, sweet potato and yams.
Chow Down on Cereal
Many cereals contain fast-digesting carbs, and these are a convenient and quick food source. Bran flakes, corn flakes, instant oatmeal and puffed rice will all give you a quick energy bump, according to the American Diabetes Association. If you add fruit juice or milk to your cereal, or if you drink it on the side, you'll get even more carbs into your meal. Other breakfast-style foods with high GI levels are bagels, rice cakes and saltine crackers.
Snack foods are notoriously high in fast-digesting carbs, and this is why they contribute so much to heavy waistlines. You should use these types of foods sparingly. Even though they are a quick, easy source of high-GI carbs, they don't have much in the way of fiber or other nutrients. Candy, chocolate, corn and potato chips, biscuits and cakes, energy bars, desserts like ice cream and frozen yogurt, and tapioca or rice puddings are very high in fast-digesting carbs.