Running to RPE in Runna: When to Switch, How to Do It (And the One Thing Runna Needs to Fix)
- 2 days ago
- 11 min read
Published August 2026
Article includes affiliate codes that supports this blog and my cancer charity work.
You open Saturday's session in Runna. It's a hilly long run, and there's a notification sitting at the top of the run description suggesting you switch from pace targets to RPE for this one.
Most runners tap straight past it. They chase the paces anyway, blow up on the third climb, and finish the run feeling like they've failed a session that was never achievable in the first place.
I've trained with Runna through rebuilding after cancer and again after emergency surgery this year, and almost everything I race is hilly. So this prompt and I are well acquainted. Here's what RPE is, when to switch, how to run to feel, and where I think Runna still has work to do.
Contents
What is RPE?
RPE stands for Rate of Perceived Exertion. It's a way of measuring how hard you're working using nothing but your own body as the instrument.
Instead of a watch telling you to run 8:45 a mile, you run to an effort level, a number from 1 to 10, based on how hard it feels. You're reading your breathing, your heart rate, how heavy the legs are, whether you could hold a conversation, and how much sweat is dripping off the end of your nose.
A Swedish researcher called Gunnar Borg came up with it back in the 1960s and coaches have used it ever since. That's genuinely all the history you need, because here's the bit that matters to you:
RPE is a pace target that adjusts itself for hills, wind, heat, tiredness and terrain. All of those things are already baked into how hard the run feels.
Your watch has no idea you're grinding up a 15% climb into a headwind on legs that did hill reps on Tuesday. You do.
The RPE scale in Runna: 1 to 10 chart
Runna uses the 1 to 10 scale, which is the version most apps and coaches have settled on. Here's roughly what each level feels like:
RPE | Effort | What it feels like |
1 | Very light | Barely more than standing still. A slightly quick walk. |
2-3 | Light | Comfortable and easy. Breathing normally, chatting away, could keep going for hours. |
4-6 | Moderate | Breathing heavier. You can hold a short conversation, but you know you're working. |
7-8 | Vigorous | Uncomfortable. Short of breath, short sentences only. |
9 | Very hard | Extremely difficult to hold. Heavy breathing, a few words at most. |
10 | Max effort | Can't talk, can't continue for long. Absolutely everything. |
The simplest way to check yourself out on the road is the talk test. At an easy effort you should be able to hold a proper conversation. As the effort climbs you drop to sentences, then phrases, then single words, then nothing at all. It's crude, it's free, and it works.
When should you use RPE instead of pace targets?
Runna's default is pace targets, and that's the right call most of the time. Paces track your progress, they rehearse race day pacing, and they give you a number to aim at.
But pace targets assume conditions you almost never actually get. Runna recommends switching to RPE when:
You're more fatigued than usual
The weather is against you, so heat, humidity or wind
You're on a hilly route
You're on trails or technical terrain
You're at altitude
You're coming back from illness or injury
Same thread runs through all of those. Your body has to work considerably harder to hit the same pace. Hold that pace anyway and you've quietly turned an easy run into a threshold session. Switch to RPE and the intensity stays where your coach intended it, whatever the day throws at you.
Why Runna recommends RPE for hilly long runs
I train for especially hilly runs. Most of my ultras are in the mountains or on terrain with a lot of elevation, and there are plenty of 10Ks, half marathons and marathons around the world on courses nobody could describe as flat.
To help you adapt, building a strong and powerful engine for not just the faster flat sections but also the hilly ones, Runna will programme hill repeats and hilly long runs into your plan. Hill reps I cover elsewhere, and if you've read that piece you'll know I describe "run hard uphill" as a 9 or 10 out of 10 effort. That's RPE, even if I didn't call it that at the time. Here I want to look at those hilly long runs and why Runna suggests you switch from pace to RPE. And I'll be honest, it does fall down a little here.
The idea of a hilly long run is endurance. Building your ability to run for longer distances while keeping the effort controlled. Look at your pace targets for these and they'll often be in the lower range, although you may notice some block or progressive runs where the pace increases for sections, usually between 1 and 3 miles.
Now introduce hills into the run. There's no way for Runna to know the exact profile of your route, and those pace targets now could look like max effort, or even impossible to achieve. That's why Runna suggests you switch to RPE for the run.
Rather than chasing a number the terrain has made meaningless, you hold a steady controlled effort and let the pace do whatever it needs to do. Slower up, quicker down, endurance stimulus intact. I may choose to switch to RPE in a race if I'm not chasing down a PB.
How to switch to RPE in Runna
There are two ways to do it, and knowing the difference matters.
Option one: the recommendation on the day. On sessions where it's relevant, like that hilly long run, Runna flags a notification at the top of the run description recommending you make the change for that run. Accept it and it applies to that session only. Everything else in your plan carries on with pace targets as normal. This is the one you'll use most.
Option two: the global setting. If you want every run in your plan guided by effort rather than pace, head to your Profile (top left) and select Units of Measure, then RPE.
Depending on your app version you may find the same setting under Plan, then Manage Plan, then Units of Measure. Re-sync your watch connection so the change pulls through. This one sticks until you change it back, so it's the setting for a whole block of trail training or a spell of cross training, not for a single Saturday.
Two things worth knowing before you tap anything.
Your watch may still show pace targets. Most smartwatches don't currently support displaying RPE based workouts, so you'll probably still see Runna's default screen with paces on it. If that's going to distract you, turn off the pace or audio cues in your watch's own settings.
You lose Pace Analysis on RPE runs. Because RPE is subjective it doesn't give a comparable performance metric the way pace does, so Runna can't run its usual analysis on it. Not the end of the world, but worth knowing if you're the sort who lives for the post run breakdown. I am.
How to actually run to RPE
Now here's where it can get complicated, because you need to run to feel.
Let me ask you a question. Do you know the difference between your RPE 5 and your RPE 6? No, I thought not. And if I'm honest with you, I find that pretty hard to determine too.
I can easily know when it's a 5 or an 8. My heart rate, breathing and the amount of sweat running down my face are all good indicators. But that nuance of 5 to 6, that's a lot harder to figure.
So how do you run to RPE?
Practice. No matter what anyone else tells you, the raw truth is this is down to you. Knowing your body, recognising the signs of when the RPE is increasing, and being able to make often micro adjustments to your pace.
A few things that speed it up:
Use the talk test on every easy run. Say a full sentence out loud every ten minutes. If it comes out in gasps, you're too high. You'll feel like an idiot. Do it anyway.
Check in at fixed points, not just when it hurts. Every mile, or at the top of every climb, give yourself a number. Only rating the run when you're suffering teaches you nothing about the middle of the scale, and the middle is where all the confusion lives.
Rate the whole run afterwards too. One number, once you've stopped. Over a block you'll see where your on the run numbers and your overall number disagree, and where you've been kidding yourself.
Cross reference with your data after the fact. Don't stare at heart rate during the run, but do look afterwards. If the effort you called a 5 sat in Z3 for 40% of the run, that's honest feedback for next time. I've been there this year while rebuilding.
It takes weeks, not days. But it keeps paying you back, not least on race day when the GPS goes haywire in a valley and knowing what your race effort feels like is the only thing keeping you honest.
How to find your RPE baselines
Before any of that nuance is useful you need to know where the two ends of the scale are.
Your top baseline. If you want to experience a heart busting RPE 10, then do, and sprint at your absolute max for 1 minute. I expect you won't be able to hold it for longer. There's your top baseline.
Your bottom baseline. That's the slowest run you can muster, barely any more than a slightly quick walk.
Everything else lives between those two. Once you've physically felt both ends, the middle stops being abstract and starts being something you can actually aim at.
Where Runna falls down (and I say this as a fan)
Those who know me will know I am one of Runna's biggest fans. But with that comes a desire for the product to keep improving, and if writing an article that knocks on that door makes them update the app for the benefit of us all, then that's a good thing.
Here's my issue.
Runna is measuring so many metrics. So why, and I'll intentionally keep this simple, can it not monitor my pace, my elevation and my heart rate to give an indication of whether my RPE is in the target range or not?
That honestly cannot be that hard for the boffins to programme.
The app already knows I'm climbing. It knows my heart rate is at 82% of max. It knows my pace has dropped by two minutes a mile. Put those three together and it could tell me, live, that I'm running this at about a 7 when the target is 5, so ease off. Not a replacement for learning the feel. A set of training wheels while you're learning it.
As it stands, switching to RPE means switching off all the guidance and going purely on instinct. For those of us who've been at this a while, fine. For someone six weeks into their first half marathon plan being told to run a hilly long run at RPE 4, that's a big ask.
Other times worth switching to RPE
Beyond the hilly long run, here's when I reach for the RPE setting.
Hot and humid days. I ran 1K intervals in a Devon sea mist earlier this summer and the humidity turned a manageable session into a slog. Effort is the honest measure on days like that. It's important runners adapt for heat, maintaining pace on a hot day is challenging and counter-productive.
Coming back from illness or injury. Your old paces sit right there in the app, quietly taunting you. I dialled my hill reps back from my usual RPE 9-10 to a controlled 7-8 while recovering from surgery, and it was the right call.
Cross training. Injured and can't run? Work your plan on the bike, the rower, the elliptical or in the pool instead. Switch to RPE and match the resistance to the prescribed number. Your plan still works even when running doesn't.
Race day on a hard course. If the course isn't flat, the weather is grim, or the GPS is unreliable, racing to effort beats racing to a pace you set in perfect conditions.
My summary
First, definitely switch to RPE when the app recommends. That notification isn't Runna hedging. It's the app admitting it can't see your route profile, your weather or your legs, and handing the decision to the one instrument that can. Trust the app and trust the training plan.
Secondly, take more notice of how you are feeling through each run. Not just when it hurts. All the way through. That's the actual skill, and no app is going to learn it on your behalf.
Thirdly, set your baselines. One minute flat out for your 10, your slowest shuffle for your 1, and start filling in the gaps between them.
Get this right and you finish your hilly long runs having actually trained your endurance, rather than having raced a set of pace targets that were never achievable in the first place.
Lace up, enjoy your miles.
FAQs
What does RPE stand for in Runna?
RPE stands for Rate of Perceived Exertion, a 0 to 10 scale measuring how hard a run feels rather than how fast you're going. Runna offers it as an alternative to pace targets.
How do I change from pace to RPE in Runna?
There are two ways to switch to RPE in Runna. Accept the recommendation Runna flags at the top of an individual run description, which applies to that session only, or go to Profile, then Units of Measure, then RPE, which changes every run in your plan. Re-sync your watch afterwards so the change carries across.
Can I use RPE for just one run?
Runna lets you apply RPE to a single run by accepting the recommendation notification at the top of that run's description. Everything else in your plan stays on pace targets. The Units of Measure setting in your Profile is the one that changes every run until you switch it back.
Why does my watch still show pace targets after switching to RPE?
Most smartwatches don't yet support displaying RPE based workouts, so your watch falls back to Runna's default screen with pace targets on it. Disable the pace or audio cues in your watch's native settings if you'd rather not see them.
Do I lose Pace Analysis if I run to RPE?
Pace Analysis isn't available for runs completed using RPE. Because RPE is subjective it doesn't produce a comparable performance metric the way pace does. You can switch back to pace targets any time you want the analysis again.
What RPE should my long run be?
A long run should generally sit at RPE 3 to 5, meaning controlled, conversational and sustainable. If you're down to short sentences you've drifted too high. Block or progressive sections within a long run will sit higher, usually around 6 to 7.
Is RPE as accurate as heart rate?
RPE and heart rate are different tools rather than better and worse ones. Heart rate lags behind short efforts and drifts upwards on long runs in the heat. RPE responds instantly but depends on your honesty and your experience. Use RPE live and heart rate afterwards as a sense check.
How long does it take to get good at running to RPE?
Most runners need a couple of months of consistent practice before RPE numbers start to feel intuitive. Telling a 5 from an 8 comes quickly. Telling a 5 from a 6 takes far longer, and most of us are still working on it.
About the author
Andy Hood is an ultra runner, cancer survivor and advocate based in Devon. He races in the mountains, on the trails and around the world, has rebuilt his running twice through illness and surgery, and writes about training, gear and racing at runningwestwardho.co.uk. He is the founder of Check Ya Balls, menswear that saves lives.
With over £27,000 raised to date for cancer charities, Andy is always finding ways to support those diagnosed with cancer.
Andy has trained with Runna throughout his rebuild. New to the app? Use promo code ANDY2 to double your free trial to two full weeks of premium access, or click here to redeem.
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