What to Eat Before a Race

When it comes to an endurance exercise like running, carbohydrates provide the most readily available form of energy for our bodies. Our bodies use glucose from carbs to help fuel our muscles so that we can continue to perform throughout our runs.

The glucose that is stored in your body is called glycogen. Unlike fat, which can be amassed in the body in almost unlimited quantities, glycogen has limited available storage in the body. Glycogen is kept primarily in your muscles and in your liver, accounting for only about 1 to 2% of your total energy stores.

A hard workout can quickly deplete glycogen levels, which could lead to fatigue and weakened performance. To avoid this, it is important that your glycogen stores are topped off before a race and your muscles have enough available glucose to get you through your event.

After roughly 90 minutes of exercise, glycogen stores in the body can become completely depleted, which can lead to muscle cannibalization. In this process, the body converts lean muscle tissue into additional glucose, which can lead to muscle soreness, stiffness, or, in more extreme cases, injury.

This is why eating small amounts of protein is so important for longer runs. Protein combined with carbohydrates in your pre-run meal can reduce tissue cannibalization and increase muscle protein synthesis, leading to prolonged and improved performance.

Glycogen is the body's main fuel for short, high-intensity workouts, but it also relies on fat during longer or less intense runs. While you don’t necessarily want to chow down on a stick of butter before running, including small amounts of healthy fats such as avocado, almonds, or nut butters in your pre-run meal can provide lasting energy for longer efforts.

Including high-fiber foods in your normal daily diet is healthy and can support the overall well-being of the intestinal tract. However, when it comes to pre-race nutrition, you’ll want to avoid eating large quantities of fiber, as it can lead to unwanted gastrointestinal distress like gassiness, bloating, and diarrhea, which can derail any race.

When considering how much a runner should eat before a race, balance is the main focus. Eating too much or not eating at all before a race will have tremendous adverse effects on your performance. The total quantity of food a runner should eat before a race is a bit of a Goldilocks situation—you don’t want too little or too much, only what is just right. During training, test different foods and portions to discover the pre-race meal that fuels you best.

• Pre-race meal: 400–700 calories, primarily from carbohydrates.
• Pre-race snack: 100–200 calories, carb-rich, eaten closer to race time to top off energy stores.

When timed correctly, these meals provide ample energy to help you perform your best on race day.

The timing of your pre-race meal and pre-race snack is also about balance. Finding that "just right" time to eat is crucial to maximizing available energy and avoiding GI distress. A good rule of thumb for timing is to aim for the following:

• Larger meal: 2-4 hours before your race
• Pre-race snack: 30-60 minutes before the start of your race

These timing windows give your body enough time to digest and absorb nutrients. To get the most from your race-day nutrition, experiment during training to find the ideal portions and timing that work best for your body.

Carb-loading is most beneficial for races lasting 90 minutes or longer, like marathons and half-marathons. For shorter races, up to a 10k, a balanced diet with moderate carbs the day before is usually all you need.

For runs longer than 60 to 90 minutes, replenishing carbs becomes important. Consume quick carbs such as energy gels, chews, or sports drinks to maintain energy and prevent fatigue. If you plan on eating during a race, practice your strategy during training to avoid an upset stomach!

Yes, moderate caffeine can boost alertness and endurance. Have your usual morning coffee or a caffeinated gel about an hour before the race, but just like with nutrition, test it during training to make sure it works for you.

For sensitive stomachs, choose bland, low-fiber foods on race day. White rice, applesauce, toast with honey, or a bagel with peanut butter (if tolerated) can all be valid options. Avoid dairy and high-fat foods, as these are common triggers for stomach discomfort.

Whatever you eat on race day should be something you've already tested on a long run or a hard workout. And once you find what works for you, we suggest locking it in. A consistent, familiar morning routine can help you feel as prepared as possible mentally and physically when you go to toe the line.

For cross-country runners, following the guidelines listed above can help set you up for success on race day. Prioritize carbohydrates to replenish glycogen, include light protein to support muscle recovery, stay properly hydrated, and always practice your nutrition plan before race day.