What is RPE?
RPE is an acronym that stands for Rate of Perceived Exertion. Originally created to describe effort in cardiovascular exercise, powerlifter and coach Mike Tuchscherer made it famous in the lifting world by porting it over to powerlifting as a way to evaluate the difficulty of a set or rep.
It’s a 1-10 Scale, but only 5-10 are really relevant. Anything below a 5 is outside the scope of realistic evaluation.
This is how Mike describes RPE, and how to rate it, in an article from 2015.
This is a fairly clear description, although some ambiguities remain, such as:
For RPE 10, what if I could’ve managed it with a few more lbs, but not enough do do an entire additional rep?
RPE 7 and below all seem pretty subjective. What’s up with that?
In this article, we will examine the 2nd of these ambiguities.
Additionally as a disclaimer, any of this RPE rating business is nonsensical until someone has been lifting long enough to have failed at least a few times, and thus know acutely what failing feelings like - as well as what it felt like leading up to that. Some people (it me) go from fast to slow to fail quickly. For others, their first rep moves almost as slowly as the one right before they fail. Most people fall in the middle. So there’s somewhat of an individualized element here, and I typically don’t recommend trying to use RPE until you’re an intermediate lifter.
Additionally I’ve found some people simply don’t have the temperament to rate their bar speed objectively. Most of those people always think the set was harder than it actually was. They constantly call easy sets RPE 8-9, and use RPE as an excuse to do less. A smaller minority of those people do the opposite and constantly under-rate their sets, calling RPE 9-10 sets as 7-8, because they want to add more weight. I’ll never forget the enraged face of one of my lifters, who just grinded his way through what had to be an 8-9 second, bone-on-bone max effort squat of 385, at our in-house competition. The squat was so slow that it lasted longer than people could continue cheering “UP!” for him, and there was a moment or two of extended silence in the whole gym while he finished grinding it out. Immediately afterwards, he came up to me with intense anger in his eyes and on his face, yelling at me that, “I TOLD YOU I COULD’VE DONE 405!!” as if the ease with which he made 385 had convinced me. My man, that 385 squat just took you longer than it took Reggie Miller to beat the Knicks, and you’re mad at me for not letting you do 405? This is a minority of people, but you will find them.
That all said, for someone who has enough experience and the right temperament for it, I’ve found RPE to be a useful tool for both communication purposes between lifter and coach, as well as the ability for a lifter to auto-regulate his training based on his actual, vs expected, performance on a given day.
The Ambiguities of RPE
Despite its utility, RPE remains a bit fuzzy. My experience has been that a well trained lifter with the right temperament can, with time and calibration, come to rate his RPE correctly within half a point most of the time. But that only really applies, based on the chart above, to RPE 7.5 and above, where we are at least attempting to be objective. What about RPE 6-7, which is listed above in purely subjective terms? How would a lifter even know what “an easy opener” should feel like, or how fast it should move, until he has done at least several meets? And even if he has done, it’s still pretty subjective and squishy.
The Imperfect Solution
I will describe here, briefly, how I navigate this issue with my lifters. It’s not perfect, but as long as the lifter meets the 2 basic criteria mentioned above (experienced enough + right temperament), it works well enough for practical purposes. Short of using a bar speed tracking device, it has worked well enough for me to stick with it for a while now. But I’m always open to better solutions that someone else may have come up with.
The first adjustment I make to Mike’s chart is to make RPE 7 objective again: RPE 7 means you could’ve done 3 more reps, but not 4. I’ve found that this level of granularity is still possible to rate accurately and precisely, by calibrating it over time just like 7.5-10. However, beyond 3 reps, you’re just too far away from max to rate with accuracy or precision if you could’ve done 4 or 5 or 6 more. There may be people out there who can do this, but I’ve not found them yet.
However, for more advanced and stronger lifters, there is also undeniably a space between “could do 3 more” and “warmup” that has to do with absolute load.
RPE 7-10 for main lifts is an attempt to be objective, while recognizing that we're humans not robots, so even a well trained lifter in rating RPE might be off by half a point here or there. That's one reason why I don't assign main lifts solely in RPE, but use with a weight or weight range or %, and then allow the lifter to make small adjustments to that based on RPE, only if needed.
RPE 6-6.5 is squishy, but not useless. If you've been lifting long enough to have failed some lifts, and been rating RPE for a long time, you should have enough of a sense of when something is "hard enough to be a work set and not a mere warmup, but easy enough that you could do more than 3 more."
Exactly how many more? Don't know, it's really impossible to rate accurately more than 3 reps from failure. It will depend on the lift and the absolute weight. The stronger you are, the lower a % of max becomes RPE 6. Like for me, even when my deadlift e1RM was above 750, it still was RPE 6 when I worked with 455, even though it was only around 60% of my max. Because 455 is still 455, even when it's a low % of max: absolute weight matters.
But take someone who’s been lifting for all of 8 weeks, squatting 225x5x3, and give him the same 60% - 135x5 - and that is literally nothing. An easy warmup. Not work at all, not contributing to any gains whatsoever - because 135 is nothing for most healthy adult males to squat. Absolute weight matters.
So there's no absolute, objective formula for RPE 6-6.5, at least not yet. It's an admittedly moving target based on absolute load, %, of max, and how much grit you have.
Below RPE 7, don’t bother trying to guess how many more reps you could do. Maybe 4, maybe 6. Who knows, it’s pointless to guess. But you should, after years of lifting and if you have the right temperament, have a sense of "was this still some work, albeit easy work, or was this just a warmup?
No Solutions, Only Trade-offs
The great Thomas Sowell is famous for this line, among other things.
What does this have to do with RPE and lifting? Using RPE 6-6.5 is admittedly squishy and subjective. It’s a tradeoff of just doing the numbers on the paper for that day, vs trying to evaluate for yourself during the workout - is this too hard or too easy for what I should be doing today? Both approaches have their advantages and disadvantages, but I’ve found over the years that, as long as we’re dealing with a lifter who has the experience + temperament to use RPE, that this grey area can be successfully navigated using extreme, brutal honesty in assessing RPE.
For example, if you’re an advanced lifter and have a heavy volume PR squat workout on Friday with 545x5x5, but are not peaking for a meet, you might want your Tuesday squats to be light, but not so light that they don’t contribute to your fitness at all. Based on recent performance and %s of max, you deduce that this should be 435 for 2-3 sets of 5. That’s a full 20% off your upcoming big volume workout. Should be easy, right?
Anyone who’s trained long enough to get their squat to 545x5x5 knows it doesn’t work that way. Some days 435 still is heavy, other days it moves like you’ve got a jetpack on. Absolute weight matters. You do your warmups and man, 365 is slow, hard, heavy. If you go by what’s on the paper, you make yourself do 435x5x3, then you’re puzzled when you can’t do 545x5x5 on Friday because you’re still gassed.
Using the concept of RPE 6 as elucidated here, however, you make the gametime call to drop down to 405 and only do 2 sets of 5 instead of 3. And then you smash the much more important, impactful sets of 545x5x5 on Friday, which are the bulk of the work for the week.
Not a perfect solution, but an acceptable tradeoff.
And usually in life, that’s all we get.