Does It Matter What You Eat the Day Before a Race?

November 9, 2025 •

4 min read

According to sports nutrition experts, strategic eating in the 24-48 hours leading up to an endurance event can improve performance by up to 3%. So, does it matter what you eat the day before a race? The answer is a resounding yes, and a well-planned nutrition strategy can be the difference between hitting a personal best and 'hitting the wall'.

Quick Summary

The importance of pre-race nutrition varies by event distance, with endurance events requiring careful carb-loading. Strategic eating maximizes glycogen stores while avoiding digestive issues. The day before a race should focus on easily digestible, carbohydrate-rich foods and adequate hydration, but specific needs depend on the race length and individual tolerance.

Key Points

Pre-race fueling is event-specific: The importance of your pre-race meal plan depends on the distance of the race. Long endurance events require careful fueling, while shorter races like a 5K have less strict requirements.
Carb-load strategically: For longer races (90+ minutes), maximize muscle glycogen stores in the 2-3 days leading up to the event by increasing carbohydrate intake and reducing training volume.
Prioritize easily digestible carbs: Focus on low-fiber, refined carbohydrates like white rice, pasta, and bagels the day before the race to reduce the risk of gastrointestinal issues.
Practice your fueling plan in training: Never try a new food or meal the day before a race. Use long training runs as a dress rehearsal to test your nutrition strategy.
Stay hydrated and manage electrolytes: Sip water and electrolyte drinks consistently in the 24-48 hours before the race. Proper hydration is critical for storing glycogen and maintaining performance.
Avoid high-fat, high-fiber, and spicy foods: These foods can slow digestion, cause bloating, and lead to discomfort during the race. Save rich meals and high-fiber foods for after the event.
Avoid overeating the night before: A moderate, carbohydrate-heavy meal the night before is better than stuffing yourself. You should wake up feeling ready, not groggy or bloated.
Timing your meals is key: Eat your last significant meal the evening before the race with enough time to digest, and consume a smaller, easily digestible breakfast 2-4 hours before the start.

For anyone participating in an endurance event, such as a marathon or triathlon, the strategic fuel intake in the days leading up to the competition is a critical component of success. Your muscles and liver store carbohydrates as glycogen, which is the body's primary and most accessible energy source during intense or prolonged exercise. To ensure these 'fuel tanks' are full at the starting line, a thoughtful approach to the day before the race is essential. While a 5K race may not require an intensive strategy, longer events depend heavily on a calculated approach to prevent fatigue and maximize performance.

The science behind pre-race fueling

What you consume the day before a race is not just about having energy but about preparing your body to sustain effort over a long duration. For races lasting longer than 90 minutes, your body's natural glycogen stores will become depleted without additional fuel. Carb-loading, which often starts 2-3 days before the race, is the process of increasing carbohydrate intake while tapering training volume to maximize these glycogen reserves. This process ensures your body has a deep well of energy to draw from, delaying fatigue and improving endurance. The day before is the final opportunity to top off these stores while simultaneously minimizing the risk of digestive distress on race day.

The importance of low-fiber, high-carb foods

Digestive comfort is a key concern for any athlete leading up to a race. The jostling motion of running and increased blood flow to the muscles can divert attention from the digestive system, increasing the risk of stomach issues. This is why the day before the race is a time to prioritize low-fiber, easily digestible carbohydrates over bulky whole grains or high-fiber vegetables. Easy-to-digest carbs are quickly processed and stored as glycogen, ensuring you wake up feeling light and energized, not bloated or heavy.

A pre-race meal plan

Here is a sample menu for the day before an endurance race to help guide your fueling. This is based on a lunch/dinner approach, but you should spread your carbohydrate intake evenly throughout the day rather than eating one massive meal.

Breakfast: Oatmeal with a small amount of banana and honey. Opt for simple oats instead of high-fiber varieties.
Lunch: White rice with a simple sauce and a lean protein source like grilled chicken or white fish.
Afternoon snack: A plain bagel with a thin layer of nut butter or a banana with some honey.
Dinner: A moderate portion of white pasta with marinara sauce. Avoid heavy, creamy, or spicy sauces that can upset the stomach.
Evening snack (optional): Some pretzels or a small piece of plain bread with jam if you feel hungry, to top off stores before bed.

Comparison of pre-race meals


Food Choice	Fiber Content	Digestion Speed	Impact on Race	Recommendation
White Rice & Grilled Chicken	Low	Fast	High glycogen availability with low risk of stomach upset.	Excellent
High-Fiber Veggie Stir-Fry	High	Slow	Increased risk of gas, bloating, and mid-race digestive issues.	Poor
White Pasta with Marinara	Low/Moderate	Fast	Replenishes glycogen stores effectively; generally well-tolerated.	Excellent
Heavy Cheese Pizza	Low (if thin crust)	Very Slow	High fat content slows digestion and can cause bloating.	Poor
Oatmeal with Honey & Banana	Low (if simple oats)	Fast	Great breakfast or snack option; provides quick, sustained energy.	Excellent
Legumes/Beans	Very High	Slow	Likely to cause significant digestive discomfort during exercise.	Poor

Hydration and electrolyte management

Just as important as your solid food intake is your fluid and electrolyte balance. Dehydration can significantly hinder performance, and it's a condition you must actively prevent in the days leading up to the race, not just on race morning. Sip water and electrolyte drinks regularly throughout the day before to ensure your cells are properly hydrated and primed for action. For every gram of carbohydrate your body stores as glycogen, it also stores about three grams of water, so adequate hydration is critical for maximizing your energy reserves.

The importance of practice

Experts stress that your long training runs are the best time to practice your pre-race nutrition strategy. You should never try a new food or meal the day before a race. By testing different foods during your training cycles, you can determine what your body tolerates best and what provides you with the most sustained energy without causing gastrointestinal distress. This practice builds a reliable fueling plan that removes an element of uncertainty on race day, allowing you to focus entirely on your performance.

Conclusion: Your last supper matters

In conclusion, what you eat the day before a race is a crucial piece of your overall race strategy, particularly for events lasting over 90 minutes. A disciplined approach to your final 24-48 hours of fueling—prioritizing easily digestible, high-carbohydrate foods while managing your fat, fiber, and protein intake—ensures your body's fuel tanks are full and ready for optimal performance. Pairing this with a consistent hydration and electrolyte plan, and sticking to foods you've practiced with during training, is the recipe for a strong, well-fueled race day. For more on nutrition timing, consider reviewing guidelines from reputable sources like sports medicine organizations.

The power of nutrition

Your final meal isn’t just fuel; it’s a psychological boost. Knowing you have meticulously prepared your body from the inside out provides confidence that you are ready for the challenge ahead. So, plan your plate wisely, trust your training, and get ready to perform at your best. This strategic fueling, when combined with your physical preparation, is what separates a good race from a great one.

Frequently Asked Questions

A moderate portion of pasta with a simple sauce is a good option. However, avoid eating a massive, heavy meal, as this can lead to indigestion and a restless night. Your carb-loading should be spread over several days, not crammed into one large dinner.

On race day morning, aim for a simple, carb-rich breakfast that you have practiced with during training. Good options include oatmeal with a banana, a bagel with a little jam, or toast. Eat 2-4 hours before the race to allow for proper digestion.

Avoid high-fiber foods (beans, lentils, whole grains), high-fat foods (fried foods, heavy sauces), spicy foods, and excess dairy. These can all cause digestive issues during your race.

No, carb-loading is not necessary for shorter races like a 5K or 10K, which typically take less than 90 minutes. For these distances, a regular balanced meal with a good mix of carbs and protein the day before is sufficient.

Sipping on electrolyte sports drinks the day before can help ensure proper hydration and top off glycogen stores, especially for longer endurance events. However, avoid overdoing it, as your primary focus should be on water and balanced meals.

Include a moderate amount of lean protein (like grilled chicken or white fish) in your meal the day before. However, avoid excessive protein intake, as it can slow digestion and is less efficient for quick energy than carbohydrates.

Yes, eating a very large, heavy, or fatty meal late in the evening can interfere with sleep quality. Aim for a smaller, easier-to-digest dinner several hours before bedtime to ensure a good night's rest.