Workout Prep: What To Eat Before Your Workout

Wednesday, September 27, 2006 - 10:03am

By Katie Clark, MPH, RD

You probably know that exercising on an empty stomach is not a good idea. However, with all the supplements, energy drinks, and hype out there, it can be confusing to know what should be in your stomach when you hit the gym. Here are some tips.

Concentrate on carbohydrates before you exercise

Complex carbohydrates are an essential component of a successful workout. Because your body eventually converts all foods into glucose—some at faster rates than others—straight glucose is your body’s preferred energy source. As the most readily converted source of energy, carbohydrates should comprise the greatest proportion of your pre-workout meals or snacks.

As a result of this fast conversion time, a small meal composed of mostly carbohydrates can exit the stomach in about one to two hours. Compare this rate to a meal that contains high amounts of protein and fat—which can take as much as several more hours to digest. This extra time can result in delayed emptying of the stomach…and potentially uncomfortable gastrointestinal side effects during your workout.

Another thing to keep in mind is that the type of carbohydrates is also important. Higher in fiber, numerous vitamins, minerals and antioxidants, complex carbohydrates are preferable to refined, simple carbs and are essential to your health.. They are found in foods such as whole grains and fruits and vegetables.

Count your calories before a workout

Eating too much before a workout can result in sluggishness and an upset stomach. But eating too little can end up leaving you hungry in the middle of your routine. Aim to eat about 200 calories within the hour before your workout. The majority of these calories should come from carbohydrates. Consider these snack ideas:

  • A half of a bagel with 1 tablespoon of sugar-free jam

  • 1 cup of cereal with 1/2 cup of skim milk

  • 6 ounces of light yogurt with 1/2 cup of fresh fruit

  • A banana and 20 mini-pretzels

  • An energy bar with less than 200 calories

Keep hydrated before, during and after exercise

Your pre-workout hydration status plays a very important role in your athletic performance. Dehydration can cause headaches, fatigue and cramping—all of which interfere with a successful workout. A good rule of thumb is to drink approximately 1 milliliter (ml) of water for every calorie you eat. For example, if you eat 2,000 calories per day, you should drink 2,000 ml of water (2 liters), or approximately 8 cups.

In addition to drinking water throughout the day, add another 20 ounces in the hour preceding your workout. If possible, sip on water during your workout, particularly if you are exercising at intense levels for more than one hour.

Meal tips to optimize your workout

Everyone responds differently to pre-workout meals. Although exercising on an empty stomach is not advisable, some people simply cannot tolerate food before a workout. If this is the case, try to eat a nutritious, high complex-carbohydrate dinner the night before a morning workout.

If you are unsure about how your body will react to a new pre-workout eating regimen, experiment with a variety of different snack and meal combinations to determine your optimal fuel food source. Never try a new, untested meal or snack idea on the day of a competitive event.

Recommended intake of food before a workout

The average woman will be adequately fueled with 200 calories of food and 20 ounces of water within the hour before her workout. Men with higher calorie needs may need 300 calories and 30 ounces of water. If you are training for a competitive event, consider meeting with a registered dietitian who specializes in sports nutrition for a food and hydration plan tailored to meet your individual needs.