No matter how fit you are and how well you’ve trained, race day fueling can make or break your race. Fueling a race properly requires the same attention to detail and practice as any other part of your preparation. Before you arrive at your “A” race, you should have practiced race day fueling in several breakthrough workouts and practice race situations.

Your race day fueling begins at least 24 hours before you stand on the starting line. On this day before the race, you want to eat with an awareness of how it will affect you the next day. Things to consider:

Glycogen Loading –24 hours is enough time to top off your glycogen stores. The day before your race, make sure that you eat carbohydrate rich foods and beverages with each meal and snack. Aim to total 4-5 grams of carbohydrates per pound of body weight during this day. For a 150 pound athlete, this means 600-750 grams of carbohydrates or 2400-3000 calories of carbohydrates. This can add up quickly if you drink many of these calories with fruit juices or energy drinks.
Fluids – Your job in the 24 hours leading up to your race is to simply ensure that you are not dehydrated. Drink often, but don’t force it. Energy drinks and fruit juices make ideal day-before drinks as they can boost your carbohydrate intake and often include electrolytes to maintain your electrolyte balance.
Sodium – If you are an athlete prone to cramping and/or weather conditions will be hot and/or humid, I would consider sodium loading in the 24 hours before your race. Eat salty foods, take some electrolyte capsules and/or drink energy drinks as part of your 24 hour pre-race nutrition.
Fiber – You want to eat enough fiber so that you can go to the bathroom before your race the next morning, but not too much. You need to know what your body needs and give it just enough. I would avoid big salads and any foods high in fiber for lunch or dinner the day before your race.

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