Back in the day, training to failure was the gold standard for productive workouts.
However, as research and practical experience grew, we learned that leaving reps in the tank was not detrimental and could even help us train more productively, stay more consistent, and keep injuries at bay.
RPE is one of the best tools to track our effort and ensure we stay within that sweet spot of just enough but not too much. So, let’s learn what RPE is, how it works, and how to use it in your training.
Key Takeaways
- RPE is a 10-point scale traditionally used in weight training to track perceived exertion and reps in reserve on individual sets. An RPE 10 means you couldn’t have done more reps; RPEs 9, 8, 7, and 6 mean you had one, two, three, or four reps in the tank, respectively.
- RPE was originally a 6-20 scale created in the 1960s to track exertion during cardio training. Mike Tuchscherer, a renowned powerlifter and coach, developed the 1-10 scale based on reps left in the tank that’s widely used today.
- Tracking RPE is generally a net positive because it helps you more accurately track your gym performance. However, beginners lack the experience to use RPE effectively and would be better off without it during their first one to two years of training.
- You should generally try to stay within an RPE 7-8 (two or three reps in the tank) on most of your sets to promote muscle and strength gains while managing fatigue.
- The Hevy app allows you to record your RPE for any set you want and monitor your effort when reviewing workout details later.
What is RPE?
RPE stands for rate of perceived exertion and is a subjective scale used to measure exercise intensity and effort. In traditional weight training, the scale goes from 1 to 10 and works like this:
- RPE 10 – couldn’t do any more reps
- RPE 9 – could have done one more rep
- RPE 8 – could have done two more reps
- RPE 7 – could have done three more reps
- RPE 6 – could have done four more reps
Anything below an RPE of 6 falls into the less challenging training category, is difficult to estimate, and is not worth logging.
As a subjective scale, RPE requires you to determine the rating for each scale, which can sometimes be unclear. For example, you may finish a set and conclude that you could have done one or two extra reps. In such cases, you can use 0.5, as in:
- RPE 9.5 – maybe could have done one more reps
- RPE 8.5 – one rep left in the tank, maybe two
- RPE 7.5 – two reps left in the tank, maybe three
The Original Borg RPE Scale
The Swedish researcher Gunnar Borg developed the original RPE scale in the 1960s to track perceived exertion levels during physical activity. It went from 6 to 20 and scaled with heart rate. An RPE 6 corresponded with a resting heart rate of around 60 beats per minute (no exertion), and an RPE 20 was the equivalent of 200 beats per minute (maximal exertion).
Borg later made a simplified RPE scale that went from 1 to 10. Like his original scale, the objective was to measure exertion, with one being no exertion and ten meaning maximum effort.
Mike Tuchscherer, an IPF champion and renowned powerlifting coach, revamped the 1-10 RPE scale in 2005 and made it into the modern, more weight-training-specific version widely used today.
His book The Reactive Training Manual introduced the modified RPE scale discussed above.
Should You Bother With Tracking RPE?
At first glance, you might wonder if you should bother with the perceived exertion scale or leave that layer of complexity to more advanced trainees.
To answer your question briefly, yes. Logging RPE will typically be a net positive because the scale allows you to track your effort. This makes it easier to work out hard enough to see progress without constantly training to failure and risking overtraining.
Research shows that training close to failure is just as beneficial as training to failure but doesn’t generate as much fatigue or affect your set-to-set performance.
For example, when logging my workouts in Hevy, I can record my RPE on any set I want and leave the value blank when I want to. I typically log my RPE on compound lifts where I try to stay at an average of two reps from failure but leave the value blank on isolation exercises like the bicep curl.
That way, besides ensuring I train hard enough, I can more effectively track my gym numbers and how they relate to my effort.
Let’s say I did four sets of 10 reps with 60 kg at an average RPE of 8 on the bent-over row last week. If I can add a rep on each set this week while keeping my RPE the same, it probably means I’ve gotten stronger.
Of course, week-to-week performance can fluctuate, so it’s better to look at long-term trends. However, having an RPE value next to each set can provide additional valuable information and help me determine if I’m improving or just putting more effort into each set.
That said, while a valuable metric to keep track of, beginners tend to be bad at estimating their RPE. This is simply because a gym newbie won’t have as much experience or understand what it feels to train to failure (or close to it) to accurately gauge how close they are to their limit on each set.
So, if you are relatively new to training, focus on the basics like learning proper form, training hard enough, gradually adding weight to the bar, and occasionally taking a set to failure to learn what it feels like, preferably on less complex exercises like curls, tricep pushdowns, and leg extensions.
How to Use RPE in Your Training
Training close to failure is stimulative and doesn’t generate as much fatigue as taking sets to failure. This means you should aim for an RPE 7-8 on most sets, regardless of whether your main goal is building muscle or getting stronger.
By controlling RPE, you can do more productive volume, recover better, and get more out of your training. Here’s a simple example:
Let’s say you’ve put 200 lbs on the bar, and that’s around 80% of your 1RM. You do a set of squats to failure and get 8 reps. The first set is so exhausting that your following sets look like this:
- Set 2 – 200 lbs x 3 reps
- Set 3 – 200 lbs x 3 reps
- Set 4 – 200 lbs x 2 reps
- Set 5 – 200 lbs x 2 reps
Mind you, this likely means training to failure across all sets. You get 18 reps total and are ready to call it a day before doing other exercises. In contrast, if you stop at five reps, your RPE for the first set will be around 7. You won’t get as fatigued, and you can get five reps across all sets, even if you climb to an RPE 9 on the last set.
As a result, you would get seven more total reps and arguably feel fresher to continue your workout. Plus, you’d be at a smaller risk of technique breakdown.
Things are not that different if you primarily train for muscle growth. Leaving one to three reps in the tank means you get most of the gains from each set while controlling fatigue. That way, you can do more total volume, recover more quickly, train each muscle the recommended two times per week, and likely grow better in the long run.
As a quick side note, stopping two or three reps shy of failure (a genuine RPE 7-8) is still hard training, especially on heavy compound lifts like the deadlift and low-bar back squat. Jeff Nippard recorded what a genuine RPE 10 looks like on multiple exercises, so you can see how much effort it takes to complete the last 2-3 reps.
Setting an RPE Cap
An RPE cap is a pre-determined effort limit that helps you maintain a high training quality without pushing yourself beyond your recovery capacity.
As noted above, that would generally mean staying between one to three reps away from failure. However, this cap can be a good way to autoregulate your training during more stressful phases of life.
For example, let’s say you’re going through a rough time (stress at work, poor sleep, newborn baby, etc.) but still want to stay consistent with your training. In such a case, you can set a lower RPE cap of around 6 and adjust your workouts to stay at a more moderate intensity.
To do that in Hevy, you can start a new workout and write your RPE values beforehand. That way, you’d get a constant reminder not to push too hard, and you can see how hard you trained when reviewing your workouts later.
Is RPE Better Than Percentage-Based Training?
Percentage-based programming is an old-school approach where you calculate your training weights based on your 1RM. For example, if your bench press 1RM is 225 lbs and a program calls for 5×5@80%, that would mean lifting 180 lbs (225 * 0.8).
You could also work up to a heavy single in each workout (close to that day’s max) and calculate percentages.
That said, programming based on RPE tends to be better because it’s more intuitive and allows trainees to autoregulate based on daily readiness. Rather than prescribing a percentage, you go by RPE targets, which always feel the same.
For example, you can program your strength sets like 5×5@RPE 8. Rather than programming percentage, you adjust the load to fit within those rules.
Another factor in favor of RPE over percentage-based programming is that the number of reps people can do at different percentages of 1RM varies. One person might do 15 reps at 70% of 1RM, whereas another might only be able to do 8.
A personal trainer or coach might give a blanket recommendation of 5×5@80% of 1RM, which might feel super heavy for one person (dangerously close to failure), just right for another, and on the light side for a third person.
In contrast, 5×5@RPE 7 or 8 will require the same amount of effort by every trainee, and it’s just the weight that changes. Check out the table below for rough estimates on the number of reps you should be able to do at different percentages of 1RM and RPE targets:
Conclusion
RPE is an effective tool to measure effort and ensure you’re training hard enough without generating too much muscle fatigue. The original Borg rating went from 6 to 20 and scaled with heart rate, which made it more suitable for monitoring exertion in cardio training.
However, the scale was made to work based on reps in reserve and is now universally used in weight training thanks to the early changes by Gunnar Borg and the later modification by Mike Tuchscherer.
Monitoring your RPE on big compound lifts can put your numbers into perspective when reviewing progress later. You can use Hevy to log your workouts, record your RPE on the sets, and exercise where it matters most.
Download the app to see how it works, or click here to learn how the RPE feature works.
Hevy – Workout Tracker
Hevy – Workout Tracker
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FAQ
1. How does RPE help with fatigue management?
RPE allows you to train hard enough without taking sets to failure. This helps you progress in your training without pushing yourself to your limit all the time. As such, you can keep fatigue under control, maintain your performance better throughout each workout, and recover better between sessions.
2. Should beginners use the RPE scale?
RPE is subjective and not as helpful for beginners because they don’t have as much experience and can’t accurately tell how many reps they have in the tank. As a beginner, focus on the fundamentals for the first year or two, then start looking into RPE tracking.
3. What’s the difference between RPE and reps in reserve (RIR)?
RPE and RIR measure the same thing: how many reps you have in the tank at the end of a training set. The only difference is that RPE goes up with 10 meaning you’ve taken a set to failure, whereas RIR goes down with 0 meaning you couldn’t have done any more reps.
