When it comes to the ultramarathon distance, it's not just about endurance and mental toughness to get to the finish line. What to eat during an ultramarathon can play a huge role in how your day goes.

Nutrition is a critical aspect of ultramarathon success. While running an ultra, your body needs a continuous supply of energy to keep moving, and this energy largely comes from the food and drinks you consume during the race. Proper fueling can make the difference between a strong finish and a difficult struggle to the end, and it's just as important as your physical training.

Whether you're new to ultrarunning or looking to refine your race day nutrition strategy, understanding the basics of ultramarathon fueling is essential. In this guide, we'll cover some key concepts of ultramarathon nutrition, including:

• Why nutrition is crucial to ultra running success.
• How carbs power your run and how much you need.
• Nutrition options like sports drinks, gels, and real food.
• How to plan your nutrition strategy from start to finish.
• How to handle nausea, cramping, and other nutritional challenges during a race.

What to Eat During an Ultramarathon: The Basics of Ultramarathon Nutrition

During an ultra, your body requires a continuous supply of energy to keep your muscles working efficiently and to maintain mental sharpness over the many hours of running. Unlike shorter races, where pre-race fueling and hydration might suffice, ultramarathons demand a proactive approach to eating and drinking throughout the event. Proper nutrition helps maintain your energy levels, prevent fatigue, and keep your body functioning optimally over long distances.

Ultramarathon Running Coach and Registered Dietician Cody Moore says, "The frequent joke is that ultra marathons are actually just an eating contest with some running in between! Generally speaking, the more you can eat, the better you're going to feel later into the race and the more energy you're going to have."

The Importance of Carbs

When running long distances, your body generally relies on two fuel sources: carbohydrates and fats.

Of these two, carbohydrates are the predominant fuel source, especially during harder efforts. When you run, your body uses stored carbohydrates (glycogen) in your muscles and liver to provide the energy needed to keep moving. Without adequate carbohydrates, your energy levels will drop, leading to fatigue, decreased performance, and the dreaded "bonk."

Unfortunately for ultra runners, the body has a limited capacity for glycogen storage, which means that these stores will eventually run out during prolonged exercise. Once those glycogen stores are depleted, your body must rely on external sources of carbohydrates.  By regularly consuming carbohydrates during your race, you can keep your glycogen levels topped up, maintain your energy, and continue running strong.

The body also uses fat as a fuel source, particularly at low intensities. However, even the leanest of athletes will have near unlimited fat stores, so consuming fat during an ultra endurance event is less important than carbs.

Start Your Nutrition Strategy By Figuring Out How Much You Burn

A key starting point for your running nutrition strategy is understanding how much energy (or kilocalories) you burn during your run. Knowing your caloric expenditure helps you determine how much fuel you need to take in to maintain your energy levels.

The MOTTIV Nutrition Calculator is a helpful tool that estimates how many calories you'll burn based on your race duration, pace, weight, and other factors. You can find the calculator here:

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How Much Fuel Do You Need?

Once you have an idea of how many calories you'll burn, the next step is to determine how much fuel to take in. A general rule of thumb is to aim to replace at least 25% of the calories burned during your run, as suggested by the MOTTIV calculator.

For example, according to the calculator, if you:

• Weigh 130 pounds
• Are doing a 50K race
• Anticipate a 5 hour finish

Your estimated calories burned would be 2340, and you should aim to replace 585 calories during the race.

Notably, the numbers in this calculator provide a minimum target, as many current studies show that greater carbohydrate consumption is correlated with faster race times. However, the amount you can tolerate will vary, and it's crucial to find a balance that your gut can handle.

Another guideline often used is to consume about 1 gram of carbohydrate per kilogram of body weight per hour. For example, if you weigh 60 kilograms, aim to consume 60 grams of carbohydrates per hour. To put this in perspective, a typical energy gel contains about 20 to 25 grams of carbs.

For some runners, this represents an upper limit, while others may find they can tolerate even more. Training is the perfect time to experiment with different amounts to see what works best for you. Pay attention to how your body responds, and use your long runs to dial in your optimal carbohydrate intake.

Don't Forget About Hydration

Proper hydration is as essential as fueling when it comes to nutrition for distance running. Water plays a critical role in nearly every bodily function, including digestion and temperature regulation. Without adequate hydration, your body won't be able to absorb and use the nutrients from the food you consume, leading to decreased performance and potential digestive issues.

Dehydration can also lead to a host of problems, including cramps, nausea, and heat exhaustion. It's important to hydrate consistently throughout the race, beginning early and maintaining regular fluid intake.

While individual hydration needs can vary, a general guideline is to aim for 16 to 24 ounces of fluid per hour, adjusting based on factors like temperature, sweat rate, and personal comfort.

The Best Food for Ultra Running

Selecting the right types of food and drink for your ultramarathon can be as important as knowing how much to consume. Different fuel sources offer varying benefits, and finding what works best for you will depend on personal preference, race conditions, and your digestive tolerance.

Sports Drinks

Sports drinks are a popular choice for many ultra runners as they provide both hydration and carbohydrates. They're an easy way to get in some of the necessary carbs while also helping to replace electrolytes lost through sweat.

Many runners and dietitians suggest separating your hydration and caloric intake, taking in both liquids and solids to meet your needs. A good balanced approach is to use a sports drink with a moderate amount of carbohydrates, such as Skratch Labs' Sports Hydration drink, while also consuming other food sources for the majority of your calories. This strategy allows you to maintain adequate hydration and food absorption, reducing the risk of digestive distress.

Gels and Other Semi-Solid Foods

Sports gels, chews, and other semi-solid foods are staple fuel sources for many ultra runners. These products are specifically designed to be easy to digest and provide quick energy, making them ideal for maintaining a steady carbohydrate intake during a race.

Gels and chews are portable and convenient and come in various flavors, allowing you to customize your fueling strategy to your preferences.

One of the benefits of using gels is their quick absorption rate, providing an immediate energy boost when you need it. However, because they are highly concentrated, it's essential to consume them with water to aid digestion and prevent gastrointestinal discomfort.

Consuming Real Food on Race Day

Real food becomes an increasingly viable option in ultramarathons, particularly in longer races where the intensity is lower and the pace is more relaxed. When running at a high intensity with an elevated heart rate, your body may struggle to digest complex or solid foods. However, in ultra races, especially those that take place over many hours or days, real food can be a welcome change from gels and sports drinks.

During ultra races, your body is likely to crave foods with more substance after many hours of consuming simple carbs. Some popular real foods that ultrarunners rely on include:

• Sandwiches
• Fruits or nuts
• Candy bars or fig bars
• Savory items like potatoes or soup

Real food can provide a satisfying alternative that helps maintain energy and satiety and can also help prevent palate fatigue, ensuring that you continue to eat and drink enough to sustain your energy levels.

Ultra Marathon Race Day Nutrition Plan

Creating a race day nutrition plan involves more than just choosing the right foods; it's about timing your intake and adjusting your strategy as the race progresses. The goal is to keep your energy levels steady, avoid digestive distress, and stay hydrated throughout the event. Below are some strategies to consider when developing your race day nutrition plan.

Ultra Running Coach Cody Moore adds this insight: "The number one reason most people don't finish an ultra is for stomach and GI complications. And so dialing in that nutrition, practicing your nutrition, and figuring out what to eat, when to eat, how often to eat, is one of the biggest things you can do in terms of preparing yourself well for these races. It's critical to do that during your training so your body is ready for your chosen fuel on race day."

Start with Mostly Liquid Carb Sources

In the early stages of the race, many runners prefer to rely on liquid and semi-solid carb sources like sports drinks, gels, and chews. These options are easier to digest when you're running at a faster pace or when your stomach is still adjusting to the effort. Starting with lighter, more easily absorbed fuels helps prevent the discomfort that can come from consuming solids too soon.

Using liquid carb sources also allows you to maintain hydration, making it easier to manage your overall intake without overloading your digestive system. As the race progresses and your pace slows, you can start to introduce more substantial foods to meet your energy needs.

Gradually Increase Solids and Quantities

As the race gets longer and your body becomes more depleted, gradually increasing your intake and introducing solid foods can help maintain your energy. Pay attention to how you're feeling and adjust your intake accordingly, ensuring you're taking in enough to keep going without overloading your stomach.

Introducing solid foods later in the race also allows you to replenish energy stores with more substantial nutrients, which can be especially helpful during longer ultras or when running at lower intensities.

Nothing New On Race Day

One of the golden rules of race day nutrition is to avoid trying anything for the first time during your event. Stick to the foods and products you've tested during your training runs to ensure that your stomach can handle them under race conditions. Even if something looks appealing at an aid station, it's best to resist the temptation to try it unless you're familiar with how it will affect your system.

Use your training to experiment with different products, flavors, and combinations. This trial and error will help you identify what works best for your body and what to avoid. By sticking with your tried-and-true nutrition strategy, you can reduce the risk of digestive issues and stay focused on your race goals.

Hydrate From the Beginning

Hydration is critical from the start of the race. Don't wait until you feel thirsty to start drinking; by then, you may already be on your way to dehydration. Establish a regular drinking schedule early on, taking in small amounts frequently to keep your hydration levels steady. This approach helps prevent the onset of dehydration-related symptoms such as headaches, fatigue, and digestive issues.

Sodium

Sodium plays a vital role in ultra runnin nutrition, helping to regulate fluid balance, nerve function, and muscle contractions. During long runs, especially in hot weather, you lose significant amounts of sodium through sgweat. Replenishing this sodium is crucial to prevent dehydration, cramping, and other performance issues.

A good starting point is to aim for about 300 to 700 milligrams of sodium per hour, though individual needs can vary. Some endurance athletes may require more, especially in extreme conditions or if they have a high sweat rate. Pay attention to signs of sodium depletion, such as cramping or lightheadedness, and adjust your intake accordingly. Experiment with different sodium sources, such as electrolyte tablets, salty snacks, or sports drinks, to find what works best for you.

Trouble Shooting Ultra Marathon Nutrition

Even with a well-thought-out nutrition plan, it's common to encounter challenges during an ultramarathon. Issues like nausea, bloating, or cramping can disrupt your race and make it difficult to stay on track. Here are some common nutritional problems and how to troubleshoot them.

Nausea

Nausea is often a symptom of dehydration, which can impair digestion and make it difficult to keep food down. If you're experiencing nausea, first check your hydration levels and try to increase your fluid intake. Taking smaller sips of water or an electrolyte drink can help rehydrate your system gradually.

If nausea persists, it may also be helpful to adjust your fuel intake. Consider switching to lighter, more easily digestible options like diluted sports drinks or small amounts of ginger ale, which can help settle the stomach. Pay attention to your body's signals and make adjustments as needed to keep moving forward.

Bloating and Burping

Bloating and burping can occur when your stomach struggles to digest the carbs you're consuming. If you experience these symptoms, slow down or temporarily stop your carb intake to give your digestive system a chance to catch up. It's also important to ensure you're adequately hydrating, as dehydration can exacerbate digestive issues.

Taking in some sodium can also help improve fluid balance, aiding digestion and reducing bloating. Be patient and give your body time to adjust, resuming your nutrition plan gradually as your symptoms subside.

Cramping

Cramping is often linked to sodium depletion or dehydration, both of which disrupt the balance of electrolytes needed for proper muscle function. If you start cramping during a race, increase your sodium intake through electrolyte tablets, salty snacks, or sports drinks. Ensuring you're drinking enough fluids to maintain hydration can also help alleviate cramping.

Gentle stretching or slowing your pace can provide temporary relief, but it's crucial to address the underlying electrolyte imbalance to prevent further issues. Adjusting your sodium and fluid intake in response to the conditions and your body's needs can help you stay cramp-free and move steadily toward the finish.

Practice Race Nutrition in Training

One of the most important aspects of ultramarathon preparation is using your training to practice your nutrition and hydration strategy. This practice allows you to test various foods, drinks, and timing to see how your body responds under different conditions.

Use Long Runs to Test Products

Your long training runs are the perfect opportunity to experiment with different sports nutrition products and strategies. Try a wide variety of foods, including gels, chews, bars, and real food options, to see what sits well in your stomach and provides the energy you need. Listen to your body and see how it reacts, noting any discomfort or performance dips, and adjust accordingly.

Wrap Up

Mastering ultramarathon nutrition is a key component of running a successful race. By understanding the basics of fueling, practicing your nutrition strategy in training, and making smart choices on race day, you can keep your energy levels steady and enjoy a strong performance.

Key points from this article include:

• Fueling with Carbohydrates: Carbs are the primary energy source for ultrarunners; aim to replace at least 25% of the calories burned.
• Hydration and Sodium: Stay hydrated from the start and replenish sodium to maintain fluid balance and prevent cramping.
• Real Food Options: As the race progresses, introduce real food to meet your energy needs and satisfy cravings.
• Practice Makes Perfect: Use training runs to test your nutrition strategy and avoid trying anything new on race day.

With the right nutrition plan, you'll be well-equipped to tackle the challenges of your next ultra marathon and enjoy the journey to the finish line. Remember, your nutrition is as important as your training, so give it the attention it deserves, and you'll set yourself up for a successful race.

For a training plan that also provides your nutrition information for every single workout, get our MOTTIV training app!  It's the only app designed specifically for regular people to accomplish ordinary things in endurance sports!

_{Article fact checked by Ultramarathon Running Coach Cody Moore.}