Running a 50k is a great personal challenge and introduction to the world of ultramarathons – especially if you’ve come from the world of 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. 

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

Why?

First off, most 50k events take place on the trails. 

Trails are a completely different setting from the flat roads on which city marathons are held. They include ups and downs, changeable underfoot conditions, 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. You need to be thinking in terms of endurance, not in terms of performance. This means revisiting your pace strategy, your goals for the race, and your fuelling.

Ready to get into the weeds of how to run your best 50k?  

Let’s jump in!

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 pavements and roads, but that’s a mistake.

Trails vary.

Sometimes you have to climb, sometimes you’re headed downhill.

Sometimes you can run, sometimes you have to watch your footing.

When training for a trail ultra, you want to start to do as much of your training in trails as you practically can (aim for at least 50%).

This gets you used to adapting your style, and speed – warning: your overall speed will be slower on trails, especially at the beginning.

Get used to dialling things back on the uphills (even walking them where necessary), and learning how to control your descent on the downhills.

Get comfortable in constantly reading the terrain 15-20ft ahead of you as you run, while simultaneously finding your footing for each step.

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

And most of all, learn to enjoy the trails!

They’re an awesome place to get some exercise and time in nature.

* * *

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

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 all-out sprint; check out the chart below.

RPE is a metric much like speed or heart-rate – but it’s one that is much more useful when you enter the world of ultra-running.

When you try and use traditional sports metrics in ultra-running, things quickly become tricky.

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 (lactic acid build-up, for example), then it can be counter-productive to try and push through the discomfort to maintain some arbitrary pace.

As for Heart Rate Zone training, this can work well enough – to a point. After bouts of intense exercise, runners experience heart rate drift – where the heart begins to pump less blood each stroke, so begins to pump faster to compensate. In other words, the pre-defined zones that HRZ training is based on no longer apply.

Which is why we recommend training to, and getting comfortable with, RPE.

RPE might at first seem a bit subjective – or, dare I say it, holistic – it is, after all, 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 pushing it too hard. It’s not rocket science – sometimes we have to just 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, and important when you make 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
  • Endurance Monsters always keep some energy in their back pocket
  • Endurance Monsters train at a variety of speeds and distances, but always race at a sustainable pace
  • Endurance Monsters keep their Rate of Perceived Exertion under 8 out of 10 (until right near the end)
  • Endurance Monsters know how to manage their fuel, water, and electrolytes as they run
  • Endurance Monsters don’t worry if they’re taking 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 fuelling or hydration.

Get your fuel, salts, or fluids levels wrong and things can go wrong pretty quickly.

Some key points to bear in mind:

1. 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’re going to eat, and when you’re going to 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!   

2. Mix it up. Don’t get all your in-race carbs from one source

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

4. Gels are awesome . . . if you can stomach them.  Gels work for most runners, but after 4+ hours of running, gels 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 up with other foods – nut butters, trail mix, and other snacks!

5. 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, 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 have been designed by me, Thomas Watson (I’m an ultrarunner myself and a UESCA-certified running coach) and have been road-tested by thousands of runners.   

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

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

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

50k ultramarathon training plan - just finish
50k ultramarathon training plan – just finish
50k ultramarathon training plan - improver
50k ultramarathon training plan - compete

6. 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+ hrs of exclusive video content, guides, and downloadable material – all designed getting 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
  • Expert videos and guides on . . .
    • Having an ultrarunning mindset
    • Balancing training with your other time commitments
    • Maintaining motivation throughout your ultra journey
  • How to become an injury-free ultra-runner
  • Strength and resistance training for improving performance and reducing injury
  • Fuelling and nutrition for ultrarunners
  • How to achieve your ultramarathon goals
  • And plenty more expert interviews, articles, and guides 
Ultra Runner's Playbook

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

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

Questions? Ideas?  Suggestions for things I’ve missed?

Let me know below! 

Thomas Watson

Thomas Watson

Thomas Watson is an ultra-runner, UESCA-certified running coach, and the founder of MarathonHandbook.com. His work has been featured in Runner's World, Livestrong.com, MapMyRun, and many other running publications. He likes running interesting races and good beer. More at his bio.