You don't have to, but it may at least help you enjoy exercising if you grab something to eat first. At least that's what nutrition and sports experts say.

Some people think they need to eat so they'll have the energy to do physical exercise. Wrong.

Energy for physical activity comes from glycogen stores in the muscles. Because glycogen stays in your muscles basically until you need it, you don't need to fuel up right before working out, says Katherine A. Beals, an associate professor in the Division of Nutrition and Department of Family Practice and Preventive Medicine at the University of Utah.

Some people think that they will burn fat and therefore lose weight faster if they don't eat. Again, wrong. All it does is starve your brain, which causes your motivation to drop.

To ensure adequate brainpower during a workout, both experts suggest a pre-session healthy carb-based snack totaling around 300 calories, like a half a bagel or some yogurt and a banana. (Early morning exercisers who simply cannot stomach food so soon before exercise should eat a snack close to bedtime the night before, Clark says.)

Furthermore, they say that it doesn't really matter when you eat, unless you're doing higher intensity of long-duration exercise. Most probably it's more of a question of what and how much you eat.

See full report from the Washington Post.

About the author: Ruth Schaffer is a Microbiologist by training and currently authors the Allergy and Biotechnology weblogs for Creative Weblogging, and a Asian travel weblog for b5media.. She is a mother to a bi-racial, bilingual, precocious 3-yr old.