How To Train For And Run 50K (+ 50K Training Plans)

Looking into joining the wonderful world of ultramarathons? 50Ks, 50 milers, 100Ks, 100 milers?

Running a 50K is a great personal challenge and introduction to the world of ultramarathons, especially if you’ve come from running half marathons and marathons.

But despite what you might hope, running a 50K isn’t just like running a marathon with a little bit extra added on at the end. 

What is 50K in miles? A 50k in miles is 31.07 miles, or 4.85 miles (7.8 kilometers) more than a marathon.

A successful 50k run requires a different approach when it comes to pacing, fueling, mindset, and training. 

Why?

Let’s get into it!

(At the end of the post, I share links to our free, downloadable 50K training plans designed to suit each level of runner.)

What Is The Difference Between Training for a 50K And a Marathon?

First off, most 50K events are trail races. 

Trails are a completely different setting from the flat roads on which city marathons are held. They often include hills, a variety of different terrain, and in general, slow you down.

Secondly, running 50K requires you to adopt an endurance-based mindset. 

Half marathons and marathons are relatively forgiving events compared to ultras. You can push yourself uncomfortably hard in a marathon, and if you blow up and bonk, you can usually still limp to the finish line.

Ultras are different.

Unless you’re an elite runner, you need to think in terms of endurance, not performance. This means revisiting your pace strategy, goals for the race, and fueling.

With that in mind, we’ve compiled our top training tips for a trail 50K so you can be prepared for race day.

How To Train For a 50K

#1: Tackling The Trails

Many 50K runners and ultra rookies are graduating from the world of city marathons to trail ultras, and that’s a transition you’ve got to manage gradually.

Many urban runners hit the trails and assume they can use the same approach they’ve employed on the roads all these years, but that’s a mistake.

Trails vary.

Sometimes, you have to climb steep hills, and sometimes, you need to tackle a downhill. Sometimes, you can run, and sometimes, you have to walk.

When training for a trail ultra, you want to spend a lot of time training on trails as you can practically do (aim for at least 50%).

This will help you adapt to trail running in general and all of the tricky terrain and elevation gain and loss that you may need to face in your race.

Warning: your overall speed will be slower on trails than on the roads, especially at the beginning.

Get used to dialing things back on the uphills (walking them when necessary) and learning how to control your descent on the downhills.

Get comfortable constantly reading the terrain 15-20 feet ahead of you as you run while simultaneously finding your footing for each step. This is especially important in single track trails that can tend to be more technical.

Depending on how extreme your race is, consider hiking poles – but learn how to run and hike with them correctly (an art form in itself).

Related: How To Go From Marathon To Ultramarathon

And most of all, learn to enjoy the trails! They’re an awesome place to get some exercise and enjoy nature.

When running on trails, you can’t be too attached to preconceived ideas of pace. As I’ve mentioned, the terrain changes constantly, and trying to hold a certain speed can be a fallacy.

So, how best to measure your effort? 

Let’s talk about RPE.

#2: Embrace RPE As Your MPM (Most Important Metric)

Too many acronyms?

Don’t worry, I’ll make this as easy as possible.

RPE stands for rate of perceived exertion, and it’s essentially a self-defined measure of how hard you’re pushing yourself: 1 being extremely light activity, 10 being an all-out sprint; check out the chart below.

RPE is a metric similar to speed or heart rate, but it’s much more useful in ultra-running and trail running in general.

Things quickly become frustrating when you try to use traditional sports metrics in ultra-running.

Let’s say, for example, you’ve got a target pace you’re trying to stick to. That’s fine for a city marathon, but when you take that to the trails, you’ll suddenly find yourself pushing hard on tricky terrain to maintain your pace and holding back on easy downhills because you’re running too fast.

Likewise, if your legs start to lock up after 42K, pushing through the discomfort to maintain some arbitrary pace can be counterproductive.

As for heart rate zone training, this can work well enough, but only to a point. After bouts of intense exercise, runners experience cardiac drift, where the heart begins to pump less blood each stroke, so it begins to pump faster to compensate.

In other words, the pre-defined zones on which HRZ training is based no longer apply.

This is why we recommend training and getting comfortable with RPE.

RPE might at first seem a bit subjective—or, dare I say it, holistic. After all, it is about listening to your body first and foremost. But that’s pretty much the point. 

If you feel like you’re pushing your body too hard, then you probably are. It’s not rocket science—sometimes, we have to not pay too much heed to what pace is on our GPS watch and listen to our body a little more.

#3: The Ultra Mindset: Become An Endurance Monster

Ultrarunners typically have a different mindset than their shorter-distance friends.

Their overall approach is concerned with endurance and survival (as in, getting to the finish line), two key tenets of ultrarunning that are important when making the leap to 50K.

Want an ultrarunner mindset? Become an Endurance Monster. Here are some of the defining characteristics of an Endurance Monster.

Endurance Monsters:

• Are humble and conservative.
• Always keep some energy in their back pocket.
• Train at various speeds and distances, but always race at a sustainable pace.
• Keep their rate of perceived exertion under 7 out of 10 (until right near the end)
• Know how to manage their fuel, water, and electrolytes as they run.
• Don’t worry if they take longer in a race than they thought they would.

(Here’s my full post on becoming an Endurance Monster).

#4: Ultramarathons Are An Eating Competition

It’s often been quoted that ultras are all about eating and drinking, and it’s true.

One of the most common issues new runners experience in ultras is poor fueling or hydration.

Get your fuel, salts, or fluid levels wrong, and things can go downhill pretty quickly, pun intended!

Some key points to bear in mind:

Practice, practice, practice.

By the time you reach the start line of your 50K, you should know exactly what you’re going to eat, how much of it you’ll eat, and when you’ll eat it.

This is because you will have practiced all of this in training. Trial different types of fuel, trial quantities, and intervals – trial everything!   

Mix up your calorie intake sources. 

Don’t get all your in-race carbs from one source. 

Gels work for most runners, but after 4+ hours of running, they can get a little monotonous and can make your stomach a little…shaky. Avoid the runs during your run by testing your gel strategy and mixing gels with other foods—nut butters, trail mix, and other snacks.

50K is a long way; you’ll want some variety in your carb intake. Try gummies, jelly beans, salty snacks, hydration with electrolytes and carbs, nuts, peanut butter and jelly sandwiches, whatever works for you.

Just make sure you try it all out beforehand.

Research your race. 

Look at the course map, course description, and elevation profile to learn what to expect so you can apply it to your training.

Figure out what’s supplied at aid stations and incorporate that into your fueling plan—if it’s compatible. The last thing you want is to eat a banana at the 40K mark and then discover your stomach can’t handle bananas during an ultra!

Ultra marathons often allow pacers if you are looking for company and help along the way.

Check for updates from the race director so you are aware of any changes to race day logistics, such as bib and packet pick up, cut-off times, race course changes, etc.

#5: Get A GPS Watch That Goes The Distance

Tracking your individual runs and seeing your overall training progress is a key part of ultramarathon training.

Logging your workouts on a platform like Strava allows you to easily revisit them later and track your overall progress (plus get support and kudos from other runners!).

To do all this, you need a good GPS watch and one with a battery life to cover ultra distances. So your regular Apple Watch probably won’t cut it.

My current pick of the crop is the COROS APEX ultrarunning watch (here’s my unbiased review); I also keep an up-to-date list of recommended ultrarunning GPS watches that you can check out here.

#6: Stick To The Plan (Get Your Free Training Plan Here)

The best way to get ultra-marathon ready is to follow a good training plan. 

Benefits of a good training plan include:

•  gradual, planned weekly mileage increases that are manageable and avoid overtraining
• a balanced training week of intense workouts, recovery time, easier runs, potential back-to-backs, strength training, and cross-training
• provides structure and guidance to your training week
• it’s been proven that simply following a training plan increases your probability of training properly and completing your running event.

Each of our ultramarathon training plans has been designed by me, Thomas Watson (I’m an ultrarunner and a UESCA-certified running coach), and has been road-tested by thousands of runners.   

They’re free to download, and you can choose the Excel/Google Sheets version to customize it around your schedule.

Check out all our ultra training plans, or click on one of the images below to see our 50K training plans!

Check out our free downloadable – and customizable – 50k training plans:

#7: Take Your 50K Training Further

If you want to get deep into ultramarathon prep, check out my Ultra Runner’s Playbook. It’s an online course with 6+ hours of exclusive video content, guides, and downloadable material—all designed to get you ready for your ultramarathon!

We cover:

• Detailed daily training plans for ultramarathons based on running ability
• Ultra training modalities broken down; in other words, how to train smart
• Ultra running strategies for success
• How to become an injury-free ultra-runner
• Strength and resistance training for improving performance and reducing injury
• Fueling and nutrition for ultrarunners
• How to achieve your ultramarathon goals
• Having an ultrarunning mindset
• Balancing training with your other time commitments
• Maintaining motivation throughout your ultra journey

Check out the curriculum for the Ultra Runner’s Playbook!

I hope the tips in this article help you on your 50K journey!