RPE stands for rate of perceived exertion. It is a scale a lifter uses to rate how hard a set felt, and in strength training it runs from 1 to 10, where 10 means no further reps were possible. An RPE of 8 means the lifter finished the set with two reps left in the tank.
It is the same idea as reps in reserve counted from the other end, and it is a way of prescribing effort rather than load. Instead of writing "squat 100kg for 5", you write "squat 5 at RPE 8" and the client works out what that weight is on the day.
The scale
The version used in strength training is the Reps In Reserve-based scale, popularised by Mike Tuchscherer and now standard in most programming.
| RPE | What it means |
|---|---|
| 10 | No more reps. A true maximum effort. |
| 9.5 | Could not do another rep, might have added load |
| 9 | One rep left |
| 8.5 | One rep left, possibly two |
| 8 | Two reps left |
| 7 | Three reps left |
| 6 | Four or more left. Speed is still fast. |
| ≤5 | Warm-up territory. Not a working set. |
Below about 5 the scale stops being useful, which is why most programs only ever prescribe between 6 and 10.
A separate 6–20 scale, the Borg scale, exists in cardiovascular and clinical settings and measures something different. If a client has come across RPE in a rehab or cardio context, it is worth checking which one they mean before you assume.
Why coaches use it
Percentage-based programming assumes a one-rep max that was true on the day it was tested, and assumes the client turns up in the same state every session. Neither holds. A client who slept five hours, is under-fed and has had a bad week at work is not going to move 85% the way the spreadsheet expects, and a client who has slept well and eaten properly is being under-loaded by that same number.
RPE lets the program self-adjust. The prescription stays the same — 5 reps at RPE 8 — and the weight moves with the athlete. On a bad day that is 90kg; on a good day it is 100kg. Both are the correct session.
For online coaching specifically there is a second reason: you are not in the room. You cannot watch bar speed and call it. An RPE rating is the closest thing you have to seeing the set, and it comes back to you as a number you can compare week to week — provided your training tools record the rating against the set rather than losing it in a chat message.
How to introduce it to a client
Most clients rate badly for the first month, and almost always in the same direction — they underestimate how many reps they had left, because a hard set feels closer to failure than it is.
What works:
Take one set to actual failure, early on, on a safe movement — a leg press or a machine row, not a back squat. Until someone has hit a genuine 10, every other number on the scale is a guess against a reference they have never experienced.
Ask for reps in reserve, not RPE. "How many more could you have done?" is a question people answer accurately. "Rate that out of ten" is not.
Prescribe a range at first. RPE 7–8 rather than RPE 8, so a client who is half a point out is still in the right place.
Check their numbers against the reps. If someone reports RPE 8 for three straight weeks and the weight has not moved, they are rating the effort of the exercise rather than the proximity to failure.
Give it four to six weeks. Accuracy improves quickly once there is a real 10 to calibrate against. The longer version of this process is in how to use RPE with online clients.
Reading the numbers you get back
An RPE rating is only worth collecting if you do something with it, and there are three patterns worth watching for across a block.
Ratings that never move while the load never moves means the client is rating the exercise rather than the proximity to failure — retrain the scale. Ratings that climb week on week at the same weight means fatigue is accumulating faster than you planned, and the deload is due earlier than the program says. Ratings that fall while the weight climbs is the one you want: the client is getting stronger and the prescription is tracking it.
None of that works if the ratings arrive in a chat message. Log them against the set.
Where RPE is the wrong tool
RPE is poor for a genuine beginner, who has neither the reference point nor the technical consistency for a rating to mean much. Use fixed loads and progress them.
It is also weak on high-rep and long-duration sets, where the last few reps feel dramatically worse than they are, and on power and speed work, where the goal is bar velocity and a low effort rating is the point.
And it is only as good as the client's honesty. Some clients round down because they do not want to look weak in front of their coach, which is a coaching problem before it is a programming one.
