Though I am talking about fitness, and my goal is to be more fit, stronger, more flexible, and better conditioned, and more capable, I remain fat, and I am likely to continue to be fat. Not only that but I’m a fat acceptance activist. So don’t be using this blog post to shame me or shame my friends about their weight, appearance, fitness, and lack or presence of any indicator of fitness you think is important. I will delete any comments that even veer close to that. Be careful.
A friend asked me to write this up and I figured why not share it? It’s been a while since I blogged.
This RPE (Rate of Perceived Exertion) system is primarily for weightlifting. The CR10 scale, which my gym uses, and which most of the gyms I’ve seen blog about it use, was invented (along with the original 6-20 scale) by Gunnar Borg. It’s used all over the weightlifting world, and it is basically for helping estimate your lifting performance based on how other, previous (previous days, previous sets, whatever) felt to you. It can be helpful for tuning your workout sets within the same day or session, and it can be helpful for setting a reasonable starting point for a workout based on a recently past workout. It’s pretty flexible and helpful I find, and my gym coaches teach it to basically everyone because it seems to help everyone figure out, by less trial and error than otherwise, where to start.
Estimating RPE for any set or lift is a very personal sense of self and capability that you sort of have to develop iteratively over time, but it is very possible to develop a sense of it.
Trainers will usually tell you that it’s based on what you’ve “got left in the tank” for any given set. If you have 3 lifts left, your RPE is @7, because it’s 10 minus whatever number of lifts you’ve got left. And it’s not like 3 lifts left that you could do with grace and dignity, lightly putting down the barbell when you’re done. It’s 3 lifts left that you struggle and gasp for and that your lifting form goes to hell over.
So by that reckoning, an RPE of @10 is the absolute most you can possibly do (at least on the last rep) of any set. Or if you fail to do all the reps you planned to do in a set because you couldn’t, that’s also a @10. A @10 is the most. And it’s easy to test to failure, but honestly you don’t get the most effective workout if you’re always pushing 10s.
The further away from @10 you get, though, the more subtle reckoning is. Most weightlifters find it difficult to know the difference between, for example, a @4 (6 left in the tank) and a @5 (5 left in the tank), and even a @6 (4 left in the tank). I don’t yet know anyone who can tell the difference between a @1, @2, or @3. At my gym we usually start keeping track around @5 or @6.
So here’s your first chart:
|@10||“I cannot do any more.”|
|@9||“MAYBE I could do one more.”|
|@8||“I could definitely do one more. Maybe two more.”|
|@7||“I could definitely do two more, maybe three or four more?”|
|@6||“I could definitely do 3 or 4 more, maybe even 4 or 5.”|
|@5||“I could definitely do at least 5 more.”|
As I said before, this is very much a matter of practice and familiarity (with your own body, capabilities, response, and tweaks). It also very much relies on feedback, which you can definitely get from both a coach or an experienced peer watching you (for instance by looking at your form when you’re not stressed versus how you tend to lose parts of it when overstressed), or you can also get a sense of if you use it with the RPE calculation chart. By using it, and trying a predicted test set and seeing if it really bears up as being at the RPE that it calculated.
Developing a sense of RPE and the practice and use of these tables is very much a feedback-based practice. You have to try it out, you have to experiment, you might also get good instruction and guidance from a physical trainer that’s familiar with the system and one that’s familiar with you and how you work out. You could also consider filiming your own sets and seeing if you can observe visible cues of different RPE ratings that you estimate for yourself (in terms of posture, form, loss of form, etc.).
Anyway, this more advanced calculation chart that uses RPE deserves some explanation. But here’s the chart itself:
We at my gym use this chart to estimate how to scale the weight on a set to hit a specific RPE, based on planned reps, and on how some prior set felt. If the prior set was a few days (or weeks) ago, you might also want to factor in some fudge factors, either heavier or lighter, depending on how you’ve been performing lately. We almost always use a calculator, because the figuring is based on percentages. Remember that you can convert a percentage pretty easily to a decimal fraction. 50% = 0.50, 75% = 0.75.
So anyway, say you do a set of Bench Presses, 5 reps, a weight of 85 pounds, and it feels like an RPE of 7.
Next you want to figure out what would be an RPE of 8, but at 8 reps.
Use the chart! Note, again, that while the chart can give you a good idea, but you should be careful not to assume it’s exactly right. The final evaluation will be what actual RPE you rate that target set. And if you’re feeling poorly that day, maybe back off 5 or 10 or 20 pounds. Or if you’re feeling better, maybe add 5 or 10, depending on the lift, and your overall current performance. But if you have a trainer, work with them. And don’t be afraid to stop in the middle of a set if it’s feeling way off.
Anyway, to use the chart, you take your current set, and look up both the reps and the RPE. So for the @7 set of 5 reps at 85 pounds, the chart says 79% (or 0.79). To get your estimated 1 rep maximum (abbrev. e1RM), divide the weight of that set by the percentage. For this set, your e1RM is 107.6 pounds. Now, to get the weight you might use to get an @8 set of 8 reps, look up the factor for that on the chart. It’s 74% (or 0.74). This time, to go back to that estimated weight, you multiply your e1RM by the factor. So multiply 107.6 pounds by 0.74 and you get: 79.6 pounds. So the chart says, based on the RPE you got in your 5 reps of 85 @7, you will probably get an @8 out of 8 reps at 79.6 pounds.
So that’s what I know about RPEs, the chart! Yay!