Race day is not the time to experiment with a food or drink you haven't tried during training, so stick with foods you know work for you. About 1½ to 2 hours before race time, eat a light 200- to 400-calorie meal, such as a banana and yogurt, a multi-grain waffle topped with fruit, a granola bar or whatever foods worked well during your training. Coffee or tea before the race is fine if you drank them without digestive problems during training, but stick with one cup.
Be sure to drink enough fluids. Hydrate with water or a sports drink before, during and after the race. Your fluid needs are individual, but one guideline is to drink three to six ounces of fluid every 15 to 20 minutes—or about every other mile—during the race.
After you cross the finish line, slowly sip fluids to rehydrate. Within an hour, eat or drink about 200 to 300 calories of carbohydrates and some protein (fruit and yogurt, a bagel with peanut butter, or hummus with a handful of whole-grain crackers are some ideas). Carbs refuel muscles with glycogen and protein helps repair them.
Good luck on your race!