What Should I Eat Before Exercising?

Our fitness expert tells you which foods will fuel your workout, plus when to eat them.

Q: What's the best snack before working out? How long before my workout should I eat it?

A: First, be sure you really need a snack. Generally, you don't need to eat before exercise unless you tend to run low on energy during your workouts, or it's been more than a couple of hours since your last meal (think an early morning workout -- how long ago was dinner?).

The best time to eat is about 30 minutes before you begin to exercise, and the best snack is one that combines carbohydrates and protein, with an emphasis on the carbs. You don't need a lot of food, by the way. For carbs, aim for the equivalent of half of a bagel or a large banana; for protein, consider a couple tablespoons of peanut butter or a small cup of low- or nonfat yogurt. If fresh food isn't an option, look for energy bars with 25 to 40 grams of carbohydrate and about 10 grams of protein. 

Best foods to avoid? Go easy on caffeine and warm fluids (which tend to speed food through your intestines) as well as milk and high-fat or high-fiber foods, all of which can upset your stomach. Eating too much fat can also slow down the absorption of carbs and leave you feeling sluggish. Avoid high-calorie snacks if you're watching your weight -- you may end up consuming more calories than you burn.

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