What Is an Ultramarathon?

Rear view of fitness woman runner running on road

lzf/iSTock/Getty Images 

Table of Contents
View All
Table of Contents

Are you thinking about doing your first ultramarathon this year? Kudos to you for embracing a challenging yet incredibly gratifying goal! From training tips to race recommendations, find everything you need to get ready for your first long-course race right here.

What Is an Ultramarathon?

An ultramarathon is any race that is longer than a traditional marathon distance of 26.2 miles. The number of races and number of finishers has grown exponentially in the last 30 years.

Ultramarathon races may be completed on either the road or a trail, though the latter is far more common. Within these categories, you’ll find both distance and time-based ultras. 

A distance-based ultra involves—like it sounds—completing a defined distance. Some of the most popular distances for ultramarathon races include 50K, 50 miles, 100K, and 100 miles.

A time-based ultra is confined by a certain number of hours, rather than distance. There are generally three different time frames used for these races—6 hours, 12 hours, and 24 hours.

Most timed ultras involve a loop course from a few miles to several miles long. Participants have the option to stop at the end of the loop for fueling or rest as needed, and can then jump back into the race.

There are also ultramarathon races within the obstacle racing circuit. Similar to the races above, participants either tackle a long-course event or complete a multi-lap timed event.

Benefits of Ultramarathon Training

Clearly, training for a long-course endurance race means you’ll spend a lot of time exercising. With that comes several benefits:

Reduced Risk of Disease

Exercise, including running, is associated with a reduced risk of many chronic diseases, like cancer and diabetes. Of course, you don’t have to jump into such an intense level of training to achieve these benefits though—if you’re a beginner runner, training for a shorter race certainly helps with disease prevention too.

Weight Loss

With all those hours running, your body is burning a lot of calories. The specific number of calories burned depends on your weight.

According to Harvard Medical School, a 155-pound person will burn about 750 calories running 6 miles over an hour. If you’re doing a 18-mile training run at that pace, you’re looking at 2,250 calories burned. 

Of course, exercise is only one half of the weight loss equation, and runners who are trying to lose weight need to also examine their eating habits.

Reduced Anxiety

While the thought of training to run 30+ miles may provoke anxiety in some people, for many runners, long hours in solitude on a trail can be just what they need to ease stress. Those hours spent in nature, embracing fresh air and getting endorphins flowing with movement, are just what the body needs sometimes to create calmness.

Personal Victory

Training and competing in an ultramarathon race challenges the body in a way that most others would never even contemplate attempting. The sense of pride when you cross the finish line is incredible.

Risks of Ultramarathon Training

It’s also important to note that there are risks that come with such an extreme exercise regimen. Here are a few to consider

Cardiac Concerns

While many people can adapt to the stress that lengthy runs place on the heart—and often benefit from improved cardiovascular health—there is also a small subset of the population in which excessive exercise may increase the risk of cardiac issues. This is particularly true for those who may have underlying heart conditions or a family history of heart problems.

Loss of Muscle Mass

Because run training for an ultramarathon is time-intensive, it may leave little availability for strength training as well. If you aren’t doing strength training, you risk losing some skeletal muscle mass (particularly in the upper body).

Adding in some simple body weight exercises (like pushups, planks, bird dogs, glute bridges, squats, and lunges) a few times a week, or doing 1 to 2 weekly weight lifting sessions, can help mitigate the risk of lost muscle mass.

Overuse Injuries

When you increase the length and frequency of your training runs, it puts more stress on the body. This is especially true on longer runs where your form starts to fade over time, leading to changes in stride and muscle use. 

Using a training plan that has a gradual progression of increasing mileage helps reduce the risk of injury. Depending on your fitness level, weight, and your body’s ability to recover, though, overuse injuries can still occur. 

How to Train for an Ultramarathon

If you’re new to the ultramarathon running scene, consider hiring a running coach that can put together an individualized training plan for you.

An endurance coach can figure out the correct proportion of slow miles to hill/speed work, the right volume of mileage for your body, and where to get started given your current fitness level.

At its core, though, ultramarathon training simply involves running frequently and gradually increasing the distance of the long runs you’re doing each week. 

There are two key differences to consider when training for an ultramarathon compared to a standard marathon road race:

  • Terrain: Since most ultramarathons are run on trails, it’s wise to structure your training plan with a lot of trail running experience.
  • Pacing: While many runners have an idea of a comfortable pace on a flat road, trails are a different experience. Trails vary in their difficulty and elevation. A mile that normally takes you 10 minutes on the road may take several extra minutes on the trail. Because of this, many ultramarathon training plans may include a combination of time-based runs and distance-based runs in order to keep you training well without frustration over pace.

If you decide to build your own training plan, here are a few tips:

Build your base. Before you start doing any race-specific training, you need to have a solid running base in place. Most people should have at least a year of solid, consistent running experience before they think about training for an ultramarathon.

Develop a training cycle. Just like you'd outline a training plan for any other race distance, the same applies for an ultramarathon. Most 50K plans (a good starting place for a beginner ultramarathoner) are around 16 to 20 weeks, building off the base you already have. You should generally be able to run at least 10 miles comfortably when starting a training-specific cycle.

Include down weeks. When you're planning your training cycle, be sure to include recovery weeks, also known as down weeks. For most athletes, this is a two week "up" and one week "down" cycle. For older athletes or those who need extra recovery time, it may be a 1:1 ratio.

Run regularly. The recommended number of runs per week will vary based on your experience, age, goals, etc - but generally 4 to 6 runs per week works well.

Include different types of runs. If you're training 5 days per week, your runs may look like this:

Some training plans will include long runs on both Saturday and Sunday so that you don't have to do one exceptionally long run during the week. For example, you might do a long run on Saturday (20 miles) and another long run on Sunday (12-15 miles) so you aren't doing a 30+ mile run in training.

As you can see, most of your runs should be at a comfortable, easy pace. This ensures you are able to complete enough mileage to prepare your body, but that you don't overly stress the body or increase injury risk.

Go long enough before your race. Assuming you want to do your first 50K race, be sure to get in a long run of at least 22 to 26 miles a few weeks out from your event. This will ensure your body can handle doing 31 miles. You don't need to do the full race distance before the event itself (though some competitive athletes may choose to do so).

Taper before the event. Tapering, or a drop in training volume, helps your body arrive at the starting line feeling fresh. Most athletes taper for about 2 weeks before an event.

Nutrition Tips for Ultramarathoners

When you’re preparing for this type of race, you’re pushing your body to its physical limits. One of the most important things you can do to support training adaptations and recovery is focusing on good nutrition. Here are some tips:

Eat a balanced training diet with all three macronutrients: While some runners are able to adapt to a low carbohydrate or keto diet during training, most will fare better on a diet that includes many sources of healthy carbohydrates, in addition to protein and fat. These healthy carbohydrates include fruits, starchy vegetables, whole grains, certain dairy products, and beans.

Stay hydrated: This applies during your workouts, but also on an everyday basis. If you start a training session dehydrated, you’ll be much more likely to experience performance issues. 

However, do not overdrink on long training runs. Drinking too much water while running can increase your risk of a dangerous condition called hyponatremia, or a dilution in blood sodium levels. Most athletes can self-regulate by drinking according to thirst.

Eat before your long runs: Your body burns both stored carbohydrates and fat during long, moderate-intensity exercise. Top off your energy stores by eating a carb-rich meal about 1 to 4 hours prior to long or intense training sessions. 

For short easy runs, you don’t need to do anything special – but generally people find better energy levels and less fatigue when they’ve eaten a good meal or snack within a few hours of their session.

Fuel well during long runs: Your body doesn’t have infinite stores of carbohydrate, so eventually, you’ll start to struggle as these reserves become depleted. By taking in carbohydrate-rich foods during exercise, you’ll help provide a continuous supply of energy to the muscles.

Use nutrition to support recovery: After an intense or long run, try to eat a meal that has both carbohydrates and protein within 30 to 60 minutes of finishing. This will help replenish glycogen stores and start the muscle repair process. 

However, recovery doesn’t stop here. Think about the rest of the day too! For example, foods like berries, tart cherry juice, and fish all have key nutrients in them that may support recovery.

Choosing an Ultramarathon Race

While it may seem as simple as browsing the internet for a nearby race, there are a few other considerations you’ll want to evaluate when choosing your ultra:


Remember that some races may require a qualifying run, so be sure to look at standards prior to signing up and plan out plenty of time between your qualifier and “A” race.

Course Terrain

Think about what the course terrain is like and elevation that you’ll encounter. Consider the terrain near you that you have available to train, and whether it will feasibly set you up for success.


Choosing a race in an appealing destination can be both a blessing and a curse. On the plus side, you’re able to see a new location and experience it in a way many others don’t get to (by foot). But traveling for a race can present challenges, from flight delays to changes in nutrition leading up to the event. Be sure to plan well and allow yourself plenty of time to get to the destination if you plan to do a non-local race.


Clearly training for an ultramarathon is a major time commitment. Be sure to choose a race that gives your body enough time to progressively ramp up mileage. Trying to quickly train for a race that's too soon can cause injuries.

Race Size

Just like any road race, some ultramarathons will draw a large field and some will be small local races. Think about which you prefer when choosing your event.

Recommended Ultramarathon Races in the US

If you’re thinking about completing an ultramarathon, these are some of the most notable races throughout the United States:

  • Western States Endurance Run: This is the world’s oldest 100-mile trail race, taking place in June each year in California. Not for the faint of heart, runners are subjected to 18,000 feet of climbing and 23,000 feet of descending to reach the finish line. It’s a legendary event that any experienced ultramarathoner would love to experience—but keep in mind it’s a lottery-based entry system.
  • Anchor Down Ultra: Known as “the smallest state’s longest race”, the Anchor Down Ultra is a time-based ultramarathon event in Bristol, RI. It includes a 6 hour, 12 hour, 24 hour, and 100 mile race (the later is built into the 24 hour race). Runners loop around a 2.45 mile course, passing beautiful waterfront scenery during this challenging (but beginner-friendly) August event.
  • Chuckanut 50K: This mountain ultra includes 5000 feet of climbing among the Chuckanut Mountain Ridge in the beautiful Pacific Northwest. Not only does this March race come highly recommended, but the race also encourages participants to give back. Part of the entry requirement is to complete at least 4 hours of service work (trail work or volunteering at a race) or to make a donation to a trail organization.
  • Wild Woman 50K: While men still outnumber women in the ultrarunning scene, that gap is starting to close a bit. This race is proof—it’s a trail marathon, relay, and 50K, specifically for women. The event takes place in June in Washington state, around the base of Mt. Adams.
  • JFK 50 Mile: This is another historic race, with the first event dating back to 1963. While the first 15 miles of the race is focused on some challenging trail running, the remainder of the race is focused on flat or lightly rolling dirt/gravel trails or paved roads.
  • Self-Transcendence 3100 Mile Race: If you are already an experienced ultramarathoner and want to give yourself the ultimate challenge, this is the race to choose. It’s the world’s longest certified road race, lasting from 6am to midnight for 52 days straight in June through August. Athletes try to hit 3100 miles during this time frame, which averages out to almost 60 miles each day, by looping around a half mile block in Queens, NY.

A Word From Verywell

Whether you've already been running for years or are just recently became intrigued at the idea of long-distance events, an ultramarathon can be a great challenge to embrace. Just be sure to check with a doctor prior to beginning training, and give yourself plenty of time to gradually prepare for your event!

Was this page helpful?
1 Source
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Harris KM, Creswell LL, Haas TS, Thomas T, Tung M, Isaacson E, Garberich RF, Maron BJ. Death and Cardiac Arrest in U.S. Triathlon Participants, 1985 to 2016: A Case Series. Ann Intern Med. 2017 Oct 17;167(8):529-535.

Additional Reading