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You are here: Home / Nutrition / Questions from the Field / How should I fuel up on CHO before a workout?

How should I fuel up on CHO before a workout?

Is it better to eat carbs the night before a workout or in the morning?

From the Field

I was reading the Warfighter Nutrition Guide and had a few questions. First, I usually run in the morning (within an hour of waking up) and was wondering the best CHO intake procedure for the night before and or the morning of. Secondly, if it is not possible to consume high GI CHO within 45 minutes of a workout, what is the best way to replenish?

HPRC's Answer

Fueling up before a workout and restoring glycogen levels after a workout

Appropriate nutritional strategies implemented before and after training are essential. The optimal content and timing of a pre-exercise meal has not been agreed upon, but consuming a meal or snack that provides 200 to 300 grams of carbohydrate (CHO) three to four hours before heavy training is ideal—that allows time for the food to be digested and for gastric emptying to occur. Since your body relies on glycogen for fuel, which can be depleted during the night while sleeping, it is important to eat something prior to your run for adequate energy to sustain you. If you run for less than an hour, eat an easily digestible carbohydrate when you get up, such as a banana, slice of whole-grain toast, or low-fat yogurt…foods that are easily digestible, low in fat, and won’t cause gastrointestinal distress while running. Additionally, sufficient fluid intake is important to maintain hydration. A run lasting more than an hour would require additional energy (food)—either have a more substantial meal more than one hour prior to the run or consume some carbohydrate during the run.

Optimal nutrient timing across the day has not been agreed upon. However, depending on the length of your early morning run, you could have an after-dinner snack—such as cereal and fruit—to help maintain your glycogen levels

After a workout, the recommendation is to consume carbohydrate and protein within 30-60 minutes to restore muscle glycogen levels and aid in recovery. Suggested carbohydrate/protein snacks include low-fat chocolate milk, 100% fruit juice (8 oz), whole-grain bread with peanut butter and jelly, low-fat yogurt plus fruit, or a commercial sports bar. Although a high-GI (glycemic index) snack is recommended, having some kind of snack is most important.

Hydrating during a run is also necessary for performance. For a run lasting longer than one hour, a beverage containing CHO should be consumed.