Eat a decent breakfast.
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"On the day of, be sure to get up three hours before the race, and get in a decent breakfast," says Nick Stanko, a distance coach at Virginia-based Peaks Coaching Group. It should be something that you know is easy to digest, with both carbs and protein. A bagel and peanut butter is Stanko's food of choice, but if you're nervous and feeling a little queasy, a high-calorie smoothie or sizable sports bar like ProBars Oatmeal Raisin Meal will do. Just be sure to eat something!