For endurance athletes, proper nutrition is just as critical as training when it comes to race-day success. Long-distance events—whether marathons, triathlons, ultramarathons, or cycling races—demand sustained energy, optimal hydration, and smart fueling strategies to keep performance at its peak. Without a well-planned nutrition strategy, even the most well-conditioned athlete can face fatigue, muscle cramps, or a dreaded bonk (sudden energy depletion).
Kevin Morgan of Pittsford NY explores essential race-day fueling strategies, including carb-loading before the event, hydration management, and in-race fueling techniques to maintain energy levels and endurance.
Carb-Loading: The Foundation of Race-Day Energy
Carbohydrate-loading (or “carb-loading”) is a well-known strategy among endurance athletes. Since carbohydrates are the body’s preferred energy source, increasing glycogen stores in the muscles before a race can delay fatigue and improve endurance.
How Carb-Loading Works
During long-distance events, the body primarily relies on glycogen stored in muscles and the liver for energy. However, these stores are limited and can be depleted within 90 minutes to two hours of intense exercise. By increasing carbohydrate intake in the days leading up to a race, athletes can maximize their glycogen reserves, extending their ability to sustain performance.
Carb-Loading Guidelines
- Start 2-3 Days Before the Race: Instead of one massive pasta dinner the night before, gradually increase carbohydrate intake over two to three days.
- Increase Carbohydrate Percentage, Not Calories: Aim for 70-80% of total daily calories from carbohydrates while maintaining your normal calorie intake.
- Choose Complex Carbs: Whole grains, rice, potatoes, quinoa, and oats provide a steady release of energy.
- Reduce Fiber and Fat Intake: Excessive fiber can cause bloating and digestive issues, while high-fat foods slow digestion.
Example Carb-Loading Meal Plan
- Breakfast: Oatmeal with banana and honey
- Snack: Whole wheat toast with almond butter
- Lunch: Brown rice with grilled chicken and roasted vegetables
- Snack: Fruit smoothie with yogurt and honey
- Dinner: Pasta with a light tomato sauce and lean protein
Hydration Strategies for Endurance Races
Hydration plays a vital role in endurance performance. Even a 2% loss of body weight due to dehydration can negatively impact speed, endurance, and cognitive function. To maintain optimal hydration, a structured approach is necessary before, during, and after the race.
Pre-Race Hydration
- Drink 16-20 oz. of water 2-3 hours before the race to ensure you start hydrated.
- Consume 8 oz. 30-60 minutes before to top off fluid levels.
- Include electrolytes if the race takes place in hot, humid conditions to prevent cramping.
Hydration During the Race
- Follow a Schedule: Aim to drink 4-8 oz. every 15-20 minutes to replace fluids lost through sweat.
- Monitor Urine Color: Pale yellow urine indicates good hydration; dark yellow suggests dehydration.
- Use Sports Drinks for Longer Races: For events lasting over 90 minutes, consuming electrolyte-rich fluids helps replace sodium, potassium, and magnesium lost through sweat.
Avoiding Common Hydration Mistakes
- Overhydration (Hyponatremia): Drinking too much water without electrolytes can dilute sodium levels, leading to dangerous swelling of cells. Symptoms include nausea, confusion, and bloating. Balance water intake with electrolyte consumption.
- Waiting Until Thirsty: By the time you feel thirsty, dehydration has already set in. Stick to a schedule to maintain fluid levels.
In-Race Fueling Techniques
Proper fueling during a race is crucial for sustaining energy and preventing bonking. While glycogen stores provide some energy, they are limited. Supplementing with carbohydrates during the race helps maintain blood sugar levels and prevent fatigue.
How Much to Consume?
For races lasting longer than 75 minutes, athletes should consume 30-90 grams of carbohydrates per hour in small, frequent doses.
Best In-Race Fueling Options
- Energy Gels (25-30g carbs per serving) – Quick absorption but may require water to prevent stomach discomfort.
- Sports Drinks (15-30g carbs per bottle) – Combines hydration with energy replenishment.
- Chews or Gummies (4-5g carbs per chew) – Easily digestible and provide a steady energy release.
- Bananas or Energy Bars – Natural carb sources for longer races.
Timing Your Fuel Intake
- Start early: Begin consuming carbs within the first 30-45 minutes of the race to prevent energy depletion.
- Take small amounts frequently: Avoid large intakes at once to prevent digestive issues.
- Combine with hydration: Wash down gels or chews with water to aid digestion.
Training Your Gut for Race-Day Fueling
Many athletes experience stomach distress due to improper fueling. To prevent this, practice race-day nutrition strategies during training to help your digestive system adapt.
Post-Race Recovery Nutrition
Once you cross the finish line, recovery nutrition becomes critical to replenish energy stores and repair muscle damage.
The 3 R’s of Recovery
- Rehydrate: Replace lost fluids and electrolytes by drinking 16-24 oz. of fluid per pound of body weight lost during the race.
- Refuel: Consume carbohydrates (1-1.2g per kg of body weight) within 30-60 minutes post-race to restore glycogen.
- Rebuild: Include 15-25g of protein in your post-race meal to support muscle repair.
Best Recovery Foods
- Chocolate milk (carb-protein balance for glycogen replenishment and muscle repair)
- Smoothies with protein powder, banana, and peanut butter
- Eggs with whole-grain toast and avocado
- Greek yogurt with granola and berries
Race-day fueling is a critical component of endurance performance. By implementing carb-loading strategies, maintaining proper hydration, and optimizing in-race fueling, athletes can maximize their stamina and avoid energy crashes. Practicing these strategies during training will ensure that come race day, your nutrition plan is dialed in—helping you perform at your best and cross the finish line strong. No matter the distance, using the right fuel can make the difference between hitting the wall and achieving a personal best.
