Studies suggest eating or drinking carbohydrates before exercise can improve workout performance and may allow you to work out for a longer duration or higher intensity. If you don't eat, you might feel sluggish or lightheaded when you exercise.

Is it OK to workout on an empty stomach?

Working out on an empty stomach won't hurt you—and it may actually help, depending on your goal. But first, the downsides. Exercising before eating comes with the risk of “bonking”—the actual sports term for feeling lethargic or light-headed due to low blood sugar.

What should I eat 30 minutes before a workout?

The best things to eat 30 minutes before a workout include oats, protein shakes, bananas, whole grains, yogurt, fresh fruit, boiled eggs, caffeine and smoothies.