Fuel Like a Ultramarathoner

How to Fuel Like a Professional Ultramarathoner: A Science-Backed Guide for Endurance Performance

Ultramarathons push the boundaries of physical and mental endurance, demanding not just preparation and determination but also strategic fueling. Proper nutrition is the cornerstone of success for ultramarathoners, ensuring sustained energy, optimal recovery, and peak performance over long distances. Whether you're training for your first ultra or striving to shave minutes off your personal best, mastering the art of fueling is essential.

In this long-form guide, we’ll break down the key principles of ultramarathon nutrition, explore the science behind fueling, and provide actionable strategies to help you fuel like a professional ultramarathoner.

Why Fueling Matters in Ultramarathon Performance

Running an ultramarathon can burn thousands of calories, depleting your body’s glycogen stores and putting immense strain on your muscles, metabolism, and hydration levels. Without a well-planned fueling strategy, you risk hitting the infamous "wall," characterized by fatigue, muscle cramps, and mental fog.

The Three Key Goals of Ultramarathon Nutrition

1. Sustained Energy: Maintain glycogen levels to fuel your muscles and avoid bonking.
2. Hydration and Electrolyte Balance: Replace fluids and electrolytes lost through sweat.
3. Recovery: Minimize muscle damage and inflammation to enhance post-race recovery.

Pre-Race Nutrition: Building Your Energy Reserves

1. Carbohydrate Loading

Carbohydrates are your body’s primary energy source during endurance events. In the 2-3 days leading up to the race, increase your carbohydrate intake to maximize glycogen stores.

• Goal: Consume 7-10 grams of carbohydrates per kilogram of body weight per day.
• Best Sources: Whole grains, rice, pasta, sweet potatoes, and fruits.

2. Protein and Fat Intake

While carbohydrates take center stage, don’t neglect protein and healthy fats.

• Protein: Supports muscle repair and minimizes breakdown during the race.
• Fats: Provide a secondary energy source for long, steady efforts.
• Pro Tip: Focus on lean protein sources like chicken, fish, or plant-based options and include healthy fats from nuts, seeds, or avocado.

3. Hydration Prep

Start the race well-hydrated. In the 24 hours before the race:

• Drink water consistently throughout the day.
• Add electrolytes to one or two servings of water to ensure sodium and potassium levels are optimized.

Fueling During the Race: Staying Ahead of Fatigue

1. Caloric Intake

During an ultramarathon, your energy expenditure far exceeds what your body can store. The goal is to replace as much of that energy as possible without overwhelming your digestive system.

• Target: 200-300 calories per hour.
• Sources: Energy gels, chews, bars, or real foods like bananas, dates, and nut butter packets.

2. Carbohydrate-to-Fat Balance

Carbohydrates remain the primary energy source during the race, but for ultra-distance events, fats also play a role in providing long-lasting energy.

• Aim for a mix of simple carbohydrates (e.g., glucose and fructose) for quick energy and complex carbohydrates (e.g., whole-grain snacks) for sustained fuel.
• Incorporate small amounts of healthy fats from options like nut butter or avocado for extended efforts.

3. Hydration and Electrolytes

Maintaining hydration and electrolyte balance is critical for performance and avoiding cramps.

• Hydration Goal: Drink 16-20 ounces of water per hour, adjusting for sweat rate and environmental conditions.
• Electrolytes: Use electrolyte tablets, powders, or drinks to replace lost sodium, potassium, and magnesium. Aim for 300-700 mg of sodium per hour.

4. Real Food Options

For ultramarathons lasting several hours or more, relying solely on gels and chews can cause flavor fatigue or stomach discomfort. Incorporate real food options such as:

• Peanut butter sandwiches.
• Rice cakes with honey or jam.
• Trail mix with dried fruit and nuts.

Mid-Race Strategies: Problem-Solving On the Fly

1. Combatting Fatigue

When energy dips, quick-digesting carbohydrates can provide a rapid boost. Opt for energy gels or drinks with caffeine for a dual hit of carbs and alertness.

2. Managing Stomach Issues

If digestion becomes an issue:

• Slow down your pace temporarily.
• Opt for bland, easily digestible foods like bananas or plain crackers.
• Sip water or a mild electrolyte solution instead of consuming solid foods.

Post-Race Nutrition: Accelerating Recovery

1. Replenish Glycogen

After the race, focus on carbohydrate intake to restore depleted glycogen stores.

• Aim for 1-1.2 grams of carbohydrates per kilogram of body weight within the first hour post-race.

2. Repair Muscles with Protein

Protein is essential for muscle recovery and reducing inflammation.

• Target 20-30 grams of high-quality protein in your post-race meal.

3. Rehydrate and Replenish Electrolytes

Replenish fluids lost during the race by drinking water and electrolyte-rich drinks.

• A good rule of thumb: Drink 16-24 ounces of fluid for every pound of body weight lost during the race.

4. Anti-Inflammatory Foods

Include foods rich in antioxidants and omega-3 fatty acids to support recovery.

• Examples: Berries, leafy greens, salmon, chia seeds, and turmeric.

Common Fueling Mistakes to Avoid

1. Skipping Pre-Race Nutrition: Starting a race without sufficient glycogen stores is a recipe for disaster.
2. Overhydrating: Drinking excessive water without electrolytes can lead to hyponatremia, a dangerous drop in sodium levels.
3. Trying New Foods on Race Day: Stick to foods and supplements you’ve tested during training to avoid gastrointestinal distress.
4. Neglecting Recovery: Failing to refuel post-race prolongs soreness and delays your return to training.

Practical Tips for Training Nutrition

1. Train Your Gut: During long training runs, practice consuming the same foods and supplements you plan to use on race day.
2. Personalize Your Plan: Everyone’s fueling needs are different, so experiment with what works best for your body.
3. Keep It Simple: While variety is helpful, don’t overcomplicate your plan. Consistency and simplicity often yield the best results.

Final Thoughts: Fueling Like a Pro

Fueling for an ultramarathon is both an art and a science. By understanding your body’s energy needs, planning your nutrition strategy, and practicing it during training, you can set yourself up for success on race day.

Remember, fueling isn’t just about getting through the miles—it’s about optimizing your performance, protecting your health, and enjoying the experience. With the right approach, you’ll not only finish strong but also recover faster, ready to take on the next challenge.