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How to Fuel For Your Next Ultra Marathon: Your Ultimate Guide

Last Updated on May 24, 2023 by Amanda Bowden

Discover the Key to Completing Your Next Ultra Marathon: Proper Fueling Strategies.

Running an ultra marathon is a challenging feat that requires immense physical and mental strength. These grueling races require incredible endurance, often spanning distances of 50 miles or more. To complete an ultra marathon successfully, it’s essential to fuel your body properly throughout the race. Without adequate fuel, you risk hitting the dreaded wall, otherwise known as bonking, and not reaching the finish line.

Fortunately, there are several strategies you can use to ensure you have enough energy to power through your next ultra marathon. In this post, we’ll cover everything you need to know about fueling for your next ultra marathon, including pre-race carb loading, during-race fueling strategies, and post-race recovery fueling.

Before we get into these we’ll also cover your frequently asked questions! Whether you’re a seasoned ultra runner or a first-timer, these tips will help you power through your next race with energy to spare.

How do you Fuel for an Ultramarathon?

So, if you’re ready to learn how to fuel for your next ultra marathon, let’s dive in!

How do you fuel while running an ultra marathon?

Fueling during an ultra marathon is a critical aspect of maintaining energy and performance over the long haul. It’s important to consume a mix of carbohydrates, electrolytes, and fluids throughout the race to keep your body fueled and hydrated. Most runners aim to consume around 200-300 calories per hour, and experiment with different fuel sources during training to see what works best for them.

How to run faster: consume bananas! Great fuel for ultra marathons.
A bunch of bananas. Image from Unsplash. Credit: Monika Guzikowska

Some popular fuel sources for ultra running include energy gels, chews, bars, real food like bananas or potatoes, and sports drinks. It’s also important to listen to your body and adjust your fueling strategy as needed.

Continue reading this article to find out more!

How do you fuel a 6 hour run?

For a 6 hour run, it’s important to have a solid fueling strategy in place to maintain energy levels and prevent fatigue. Similar to an ultra marathon, aim to consume a mix of carbohydrates, electrolytes, and fluids throughout the run to keep your body fueled and hydrated. Most runners aim to consume around 200-300 calories per hour.

Depending on personal preferences and digestive capabilities, you may choose to fuel with energy gels, chews, bars, real food like fruit or crackers, or sports drinks. Experiment with different fuel sources during training to see what works best for you. Read the section ‘During-Race Fueling Strategies’ further into this article to find out more.

How should I eat before an ultramarathon?

Before an ultramarathon, it’s important to focus on carb-loading and staying hydrated to maximize glycogen stores and electrolyte levels. Aim to consume complex carbohydrates like pasta, rice, or potatoes in the days leading up to the race, and be sure to drink plenty of fluids.

On the morning of the race, aim to eat a balanced breakfast with a mix of carbohydrates, protein, and healthy fats. Some popular pre-race breakfast options include oatmeal, toast with peanut butter, or a banana with almond butter.

To find out more read the section further down this article called: Pre-Race Fueling Strategies.

How do you fuel a 100 mile run?

Fueling for a 100 mile run requires careful planning and preparation. Similar to other ultra marathons, aim to consume a mix of carbohydrates, electrolytes, and fluids throughout the race to keep your body fueled and hydrated. Most runners aim to consume around 200-300 calories per hour.

It’s important to have a variety of fuel sources on hand, including energy gels, chews, bars, real food, and sports drinks. Be sure to experiment with different fuel sources during training to see what works best for you. Additionally, it’s important to listen to your body and adjust your fueling strategy as needed.

To find out more read the section ‘During-Race Fueling Strategies’ further into this article.

Can you run an ultra without eating?

An exhausted runner! Make sure to fuel for your ultra marathon to give yourself the energy you need.
An exhausted runner. Image from Unsplash. Credit: Elisa Kennemer

While it’s technically possible to run an ultra marathon without eating, it’s not recommended. Consuming calories and staying hydrated is crucial for maintaining energy levels and preventing fatigue during a race of this distance.

Most runners aim to consume around 200-300 calories per hour, and experiment with different fuel sources during training to see what works best for them. It’s important to have a solid fueling strategy in place for optimal performance and overall health.

What is the salty food for ultra running?

Salty crisps, or potato chips, perfect to eat during an ultra marathon run.
Salty potato chips. Image from Unsplash. Credit: Mustafa Bashari

During an ultra marathon, it’s important to consume a mix of carbohydrates, electrolytes, and fluids to keep your body fueled and hydrated. Some popular salty fuel sources include pretzels, salted potatoes, and salted nuts and potato chips or crisps. Sports drinks and electrolyte tablets are also a good option for replenishing lost sodium.

It’s important to listen to your body and adjust your fueling strategy as needed, as everyone’s needs are different.

How many calories per hour for ultra?

During an ultra, it’s recommended that runners consume between 200 and 300 calories per hour to maintain energy levels and performance. This is a lot less than the calories you burn per hour though, see next question!

The reason you should consume less calories than you’re burning is because your body can only absorb about 240 to 280 calories per hour. This means that you may not be able to fully replenish the calories you burn, but eating frequently throughout the race can help prevent a sudden drop in energy known as “bonking.”

It’s important to note that everyone’s nutritional needs are different, so it’s a good idea to experiment with different foods and amounts during training to figure out what works best for you.

How many calories does an ultra marathon burn?

The number of calories burned during an ultra marathon varies depending on a number of factors, including the distance, the terrain, and the runner’s weight and metabolism. However, on average, runners can expect to burn anywhere from 400 to 600 calories per hour during an ultra marathon. This is less than the amount of calories you’d normally expend running as ultras are usually run at slower paces with sections walked.

If you go all out on your ultra and run the whole thing you can expect to burn between 600 and 1000 calories per hour, depending on your size and muscle mass.

Therefore if you burn the minimum amount per hour of 400 calories you would burn 2400 calories during a 6 hour ultra. If your ultra takes you 24 hours you will be likely to burn 9,600 calories, although this is dependent on how many breaks you take! The average amount of calories burned during a day long ultra is 3,500 to 8,000 calories.

What should I drink during an ultra?

A sports drink. What's it best to drink to fuel your ultra marathon?
Image from Unsplash. Credit: Martin Sanchez

During an ultra, it’s important to stay well-hydrated to maintain performance and avoid dehydration. You should aim to consume fluid at a rate of 300 to 800ml an hour, or more if it’s hot or you’re sweating heavily. Water is a good choice for shorter runs, while electrolyte sports drinks can help replace lost fluids and minerals during longer runs.

It’s important to experiment with different hydration strategies during training to figure out what works best for you. Be careful not to overdo it though, drinking too much can cause digestive distress, or on a more serious note: hyponatremia.

In 1983, two ultramarathon runners were hospitalized with hyponatremic encephalopathy after consuming excessive amounts of free water during an 80 and 100 km race in Chicago. This led to water intoxication, causing hyponatremia due to the retention of dilute fluids and excessive sweat sodium loss. The sudden absorption of fluid after exercise and further dilution of plasma sodium could have contributed to the onset of symptoms. This incident highlights the importance of proper hydration and electrolyte balance in ultra-endurance events.

How do you stay awake for an ultra marathon?

Falling asleep during an ultra marathon.
Image from Unsplash. Credit: Kal Visuals

Staying awake during an ultra marathon can be a challenge, especially if the race is overnight or lasts more than 24 hours. Some strategies to stay alert and focused include taking short naps, consuming energy gels, listening to music or podcasts, and engaging with other runners.

In addition to this, some runners may opt for caffeine to stay awake during an ultra. However, it’s important to use caffeine strategically and sparingly, as too much caffeine can lead to dehydration, gastrointestinal issues, and other negative side effects.

Finally, getting enough sleep in the days leading up to an ultra can also help you stay awake and alert during the race. Aim for at least 7-9 hours of sleep per night in the week leading up to the race, and avoid staying up late or pulling all-nighters in the days before the event.

How do you fuel a 50k ultra marathon?

Fueling for a 50k ultra marathon is similar to fueling for any other ultra race. You should aim to consume between 200 and 300 calories per hour, mostly from easily digestible carbohydrates like gels, chews, and sports drinks. It’s also important to stay hydrated by drinking plenty of fluids throughout the race.

Keep reading to find out more about ultra fueling strategies.

How do you prevent digestive issues during an ultra?

Suffering from digestive issues or ‘runners trots’ during a race can be a nightmare for any ultra marathon runner. Not only can it be incredibly uncomfortable (and embarrassing!), but it can also greatly impact your performance and potentially ruin your race. That’s why it’s essential to take steps to prevent digestive issues before and during your race. In this section, we’ll cover some tips to help you avoid this unpleasant experience and keep you on track towards the finish line.

Experiment with foods during training: Practice eating different foods during long training runs to see which ones work well for you and which ones don’t. This will help you avoid unpleasant surprises on race day.

Avoid high-fiber and high-fat foods: These foods can be difficult to digest and may cause gastrointestinal distress during an ultra. Stick to easily digestible foods like simple carbohydrates (such as white rice, potatoes and bananas) and lean proteins (such as chicken or fish) in the days leading up to the race.

Stay hydrated: Dehydration can exacerbate digestive issues, so it’s important to stay hydrated during the race. As mentioned earlier, aim to drink about 300-800ml of fluid per hour, and experiment with different hydration strategies during training to figure out what works best for you.

Take it easy at aid stations: While it’s important to refuel and rehydrate at aid stations, be mindful of how much you’re consuming at once. Overeating or drinking too much too quickly can overload your digestive system and cause issues later on in the race.

Do you need to carb load for an ultra marathon?

Carb loading, or consuming extra carbohydrates in the days leading up to a race, can help increase glycogen stores in the muscles and improve endurance. While carb loading is not strictly necessary for shorter ultra marathons, it can be beneficial for longer races like 100 milers. However, it’s important to remember that carb loading should be done gradually and with healthy, nutrient-dense foods.

To find out more read the following section: Pre-Race Fueling Strategies.

Pre-Race Fueling Strategies

Runners on the trail running an ultra marathon.
Image from Unsplash. Credit: Luke Baum

Before you even start your ultra marathon, it’s important to properly fuel your body in the days leading up to the race. This process is known as carb-loading, and it involves increasing your intake of carbohydrates to maximize the amount of glycogen stored in your muscles.

During carb-loading, aim to consume around 3-5 grams of carbohydrates per pound of body weight each day. This means that a 150-pound runner would need to consume between 450-750 grams of carbohydrates each day leading up to the race.

Some examples of high-carb foods you can incorporate into your pre-race meals include:

  • Pasta
  • Rice
  • Bread
  • Sweet potatoes
  • Oatmeal
  • Fruits, such as bananas, apples, and berries

It’s also important to stay hydrated in the days leading up to the race. Aim to drink at least 64 ounces of water each day, and consider incorporating electrolyte-rich drinks like sports drinks or coconut water to help replenish your electrolyte stores.

On the morning of the race, aim to eat a high-carb, low-fiber breakfast that you know your stomach can tolerate. Some good options include a bagel with peanut butter, oatmeal with fruit, or a banana with a side of toast.

By properly fueling your body before the race, you’ll give yourself the best chance of starting the race with a full tank of glycogen and feeling energized and ready to tackle the miles ahead.

During-Race Fueling Strategies

Once the race begins, it’s important to continue fueling your body to maintain energy levels and prevent bonking. The key is to consume a balance of carbohydrates, electrolytes, and fluids to keep your body fueled and hydrated.

There are several different types of fuel that you can use during the race, including gels, chews, sports drinks, and real food. The best option for you will depend on your personal preferences and what your stomach can tolerate. It’s a good idea to experiment with different fuel options during training runs to see what works best for you.

As a general rule of thumb, aim to consume around 30-60 grams of carbohydrates per hour of running. This might look like:

  • One gel packet (usually containing around 25-30 grams of carbs)
  • A handful of chews (usually containing around 20-25 grams of carbs)
  • Half a sports drink bottle (usually containing around 15-20 grams of carbs)
  • A banana or energy bar (usually containing around 25-30 grams of carbs)

These No-Bake Oatmeal Energy Balls are the perfect high carb snack for the trail.

Maintaining proper hydration levels throughout the race is crucial for optimal performance and overall health. A good guideline is to aim to consume around 300-800ml of fluid every hour. This might mean carrying a hydration pack or wearing a hydration belt to ensure you have access to fluids throughout the race.

Finally, don’t forget to listen to your body and adjust your fueling strategy as needed. If you’re feeling sluggish or low on energy, try consuming a bit more carbohydrates or electrolytes to see if it helps. Conversely, if you’re feeling nauseous or experiencing stomach upset, try scaling back on your fuel intake or switching to a different type of fuel.

Post-Race Recovery Fueling Strategies

Once you cross the finish line, it’s important to focus on recovery and refueling to help your body recover and repair from the physical stress of the race. The key is to consume a balance of carbohydrates and protein to help replenish glycogen stores and aid in muscle recovery.

Immediately after the race, aim to consume a high-carb snack or meal within 30 minutes to help jumpstart the recovery process. Some good options include:

  • A banana with peanut butter
  • A bagel with cream cheese
  • A recovery shake made with fruit and protein powder
  • Chocolate milk

Within 1-2 hours of finishing the race, aim to consume a balanced meal containing both carbohydrates and protein. Some good options include:

  • Grilled chicken with brown rice and vegetables
  • A shrimp and avocado sandwich on whole grain bread
  • Grilled salmon with sweet potatoes and greens
  • Quinoa salad with black beans, veggies, and avocado

Ensuring proper hydration after the race is just as important as during, as it aids in the recovery process and helps prevent dehydration-related complications. Aim to consume at least 1 and a half litres of fluid for every kilogram of body weight lost during the race. Don’t drink this all at once though!

Finally, don’t forget to give your body time to rest and recover after the race. Aim to get plenty of sleep and take a few days off from running to allow your muscles to recover fully.

By following these post-race recovery fueling strategies, you’ll give your body the nutrients it needs to recover quickly and be ready for your next running challenge.

Fuel Your Success: Essential Tips for Ultra Marathon Fueling Before, During, and After the Race.

In conclusion, fueling for an ultra marathon is a key aspect of preparing for and completing a race of this distance. By properly fueling your body before, during, and after the race, you can ensure that you have the energy and nutrients you need to perform at your best and recover quickly.

During the pre-race period, focus on carb-loading and staying hydrated to maximize your glycogen stores and electrolyte levels. During the race itself, aim to consume a balance of carbohydrates, electrolytes, and fluids to keep your body fueled and hydrated. And after the race, focus on consuming a balance of carbohydrates and protein to aid in recovery and muscle repair.

Remember, everyone’s fueling needs are different, so it’s important to experiment with different fuel options during training runs to see what works best for you. And don’t forget to listen to your body and adjust your fueling strategy as needed.

With these tips and strategies, you’ll be well on your way to fueling for your next ultra marathon and conquering the miles ahead!

If you enjoyed this article you may also like Scott Jurek’s Diet: What Does The Champion Ultra Runner Eat to Stay Strong?