As a UESCA-certified running and triathlon coach I work with a lot of half marathons and marathon runners.
Although many marathon runners are content with the challenge of the marathon distance and want to work on improving their marathon race times some avid marathoners want to push themselves physically and mentally by stepping up to the “king” of long-distance running races: ultramarathons.
Transitioning from marathons to ultramarathons can take time and patience, just as it does when you build up from the 10k to the half marathon or the half marathon to full marathon races.
However, the world of ultra running is vast and diverse, and many long distance runners who are accustomed to the competitive atmosphere of road races love the more laid-back atmosphere and camaraderie of the ultrarunner community as well as connecting with nature on the trails.
In this guide to going from marathon to ultramarathon training and racing, we will discuss key training tips for ultramarathon training to help experienced marathoners have a positive first ultramarathon race day.

What Is An Ultramarathon?
Before we discuss how to train up from the marathon to ultramarathon, let’s quickly cover the basics of ultrarunning:
An ultramarathon is any race longer than a standard marathon (26.2 miles or 42.19 kilometers). Ultra races are usually, but not always, run on trails.
Ultramarathons include 50ks, 50 mile races, 100-mile races, 200 milers, 24-hour races or other timed events, and anything between or beyond.
How Do I Transition From A Marathon To Ultramarathon?
Here are some top tips for transitioning from the marathon to ultramarathon distance:
#1: Follow An Ultramarathon Training Plan
If you are keen on transitioning from the marathon distance to ultramarathon racing, you have clearly put in the time building up to marathon and have an understanding that distance running takes dedication, structured workouts, and a gradual progression in volume to prepare you for race day.
Therefore, it should come as no surprise that working with a running coach or following an ultramarathon training plan is essential for preparing for an ultra race.
As with marathon training plans, the best ultra marathon training plan for you will depend on your fitness level, the type of ultra race you are doing (road racing vs trail running), the ultra distance you are training for as well as the type of training you tend to do well with.
Marathon Handbook offers many free ultra marathon training plans, some of which are great beginner ultra race training plans, whereas others are intended for more experienced runners.
Most likely, if you are working on building up from the marathon distance to your first ultra marathon, you should pick one of the beginner ultra marathon training plans.

#2: Start Small
It probably seems somewhat like an oxymoron to have a “short“ ultra race, but because the world of ultramarathon running encompasses any race distance that is longer than 26.2 miles, even a 50k is considered an ultramarathon.
As a running coach, I highly recommend that you choose a 50k or perhaps 50-miler as your first ultra race rather than jump up to a 100-mile ultra marathon or a timed running event such as a 24 hour race.
After you have tackled transitioning from the marathon to shorter ultra distances, you can build up to the big long-distance beasts like the 100 milers and longer stage races or multi-day trail running ultra races.
#3: Start Trail Running
Although there are plenty of ultra road races, the majority of ultramarathons are trail races whereas most runners are accustomed to road half marathon and road marathon races.
This is one of the main differences in the training plans and preparation for a marathon vs ultramarathon running.
Even at shorter distances, transitioning from road running to trail running can take some time for beginners.
Running off-road terrain requires more agility, balance, ankle and hip stability, core strength, and differences in your running technique.
Technical trails often require you to shorten your stride length, and you may even have to interspersed brisk walking on steep uphills and descents.
It is very important to train on off-road terrain if your ultra race is going to be a trail running event so that you can get accustomed to the challenges of running on trails.
I often encourage ultramarathon runners to do their tempo runs and speed work on cross-country courses (such as those at your local high school or university), as they should have distance markers for interval training, and you’ll get experience with running fast off roads.
Most longer distance ultramarathons also have a significant elevation gain over the course of the ultra trail race, as you may be going over significant mountains to get to the finish line.
Practicing hill training as speed work will help build up strength in your glutes, hamstrings, calves, and cardiovascular capacity.
I also recommend doing fast packing, stair climbing, and hiking mountains as a great way to supplement your weekly mileage running with low-impact cardio for these types of ultra trail races.

#4: Get the Right Ultra Running Gear
Running ultramarathons requires different running gear than you have likely needed in your marathon road running races.
Trail running shoes are a must to improve traction and stability on uneven terrain.
You will also need to carry a hydration pack to have fluids, energy gels, or whatever source of carbs, electrolytes, and hydration you will need for the ultra distances you are running.
Even though there should be aid stations during an ultrarunning event, the aid stations are often very far apart.
Plus, you can’t guarantee that there will still be food and fluids that agree with you at the aid stations, depending on how your race is going and your average running pace.
Here are some other helpful pieces of ultrarunning gear, some of which may only be necessary for training but not race day, depending on the ultra distances you are racing, the ultra courses, and the weather conditions:
- Ultrarunning poles
- Gaiters
- Visor/running cap
- Extra running socks
- Collapsible water bottle
- Lightweight waterproof running jacket
- Lightweight insulated running jacket, especially if you are going to be running an altitude or experiencing a lot of elevation gain
- Headlamp with extended battery life
- GPS running watch with excellent battery life. I love the COROS APEX 2 Pro GPS Outdoor Watch. It’s light, thin, and has every feature you’d need for distance running. Plus, the COROS Apex 2 Pro battery life is up to 75 hours on GPS, which is great for ultrarunners. The GPS accuracy seems excellent, and I don’t have trouble with the signal dropping, but you can always pair the watch with the COROS Pod 2 foot pod. This is sort of a backup for adding accuracy with trail running.
- First aid kit
- Radio/satellite for emergencies
- Ginger chews

#5: Practice Fueling
There won’t be any aid stations on your training runs, so you need to not only practice carrying your food, but also drinking and eating solid food for ultras.
The fueling strategy for ultrarunning can be its own beast,1Costa, R. J. S., Knechtle, B., Tarnopolsky, M., & Hoffman, M. D. (2019). Nutrition for Ultramarathon Running: Trail, Track, and Road. International Journal of Sport Nutrition and Exercise Metabolism, 29(2), 130–140. https://doi.org/10.1123/ijsnem.2018-0255 as many ultra runners find that they get nauseous or start to get palate fatigue from eating sweet energy gels, energy bars, or other typical sports supplements mile after mile.
Generally, many ultra runners find that alternating between salty, savory, and sweet foods can help prevent stomach issues and make your intake of carbs and calories a little more appealing.
As with marathon training, use your ultramarathon training long runs to practice your hydration and fueling strategy and also to find the best hydration pack, trail running shoes, and ultramarathon racing kit that will work best for you.
Some of the most popular foods for ultramarathon fueling include fig newtons, peanut butter and jelly sandwiches, dried fruit, trail mix, pretzels, energy bars, chips, jerky, chicken noodle soup, tortilla roll-ups, waffles, potato wedges, homemade rice krispie treats, and ramen.

#6: Don’t Fear the Long Run
As with marathon training, ultramarathon long runs are key for building physical2Hellsten, Y., & Nyberg, M. (2015). Cardiovascular Adaptations to Exercise Training. Comprehensive Physiology, 6(1), 1–32. https://doi.org/10.1002/cphy.c140080 and mental endurance and preparing you for race day.
If you’re already a marathon runner, it probably comes as no surprise that your longest long run before your ultramarathon race day will likely be significantly shorter than the distance you are planning to race, especially for 100 mile races and longer distances.
At a certain point, the benefits of a long run for an ultramarathon follow the law of diminishing returns. You won’t reap any additional benefits running 6 to 8 hours in a single long run instead of 4-5 hours max.
Rather, your weekly mileage, coupled with a moderate weekly long run, greatly contributes to your ability to complete whatever distance your ultramarathon race is.
Another great ultramarathon training strategy is to do back-to-back long runs.
Back-to-back long runs help you get used to running on tired and sore legs and offer the benefits of running super long runs in a more practical and approachable way.
For example, an ultramarathon training plan for a 50-mile ultramarathon or 100k ultra (62 miles) might include two consecutive 25-30 mile (40-50k) long runs in the buildup.
This means you will run 25-30 miles one day and 25 miles the next day.
Keep in mind that the more closely you can replicate the conditions of your race for your longest long runs, the better.
In other words, assuming your ultramarathon takes place on the trails, make sure your long runs are also trail runs.
The mental benefits of the long run, particularly for an ultramarathon, cannot be overstated.
An ultramarathon is indeed a test of one’s willpower, mental strength, focus, positive attitude, and ability to push through when things get boring, difficult, or downright exhausting and painful.
Long runs for an ultramarathon force you to practice entertaining your mind, staying focused, problem-solving, and not giving up or stopping when you get tired or uncomfortable.

#7: Don’t Be Intimidated
A 50k ultramarathon isn’t much longer than a standard marathon, which is 42.2 kilometers.
Therefore, a 50 kilometer ultra race is only 5 miles longer than a marathon race, so the main difference is really in the terrain, assuming you’re transitioning from a road marathon to a trail ultra.
As such, most 50k races are run at a slower pace than a marathon race due to the inherent difficulty of the terrain, so some ultrarunners find that running a 50k race is less intense than a road marathon race.
This means that you will be running at a lower heart rate and a lower percentage of your VO2 max, allowing your muscles to burn relatively more fat3Hughes, D. C., Ellefsen, S., & Baar, K. (2017). Adaptations to Endurance and Strength Training. Cold Spring Harbor Perspectives in Medicine, 8(6), a029769. https://doi.org/10.1101/cshperspect.a029769 rather than carbohydrates compared with half marathon and marathon running.
Although this certainly doesn’t mean you don’t have to worry about glycogen depletion or fueling with carbs during ultras—or that ultras are easier than marathons—it just can help marathon runners aspiring to become ultramarathon runners feel less intimidated by their first ultramarathon.
Believe in yourself.
If you want to run an ultramarathon and you’ve already completed a marathon, you’re well on your way, and your goal should be within reach.
Don’t forget to join the Marathon Handbook Facebook group for more training tips from fellow ultra runners!

Hi Maria,
I am running my first 100k ultra in 2 weeks that article really hit home. Great motivation, thank you so much for making me realise it will be painful but OK!
Cheers
Pete
Hi Pete,
How exciting! Good luck with your 100k! Enjoy the ride ๐
Glad you enjoyed the read, check out this one on my experience running my first 100k: https://marathonhandbook.com/10-lessons-i-learned-from-my-first-100k/
Maria