What RPE means
RPE on the modern resistance-training scale (Zourdos 2016) is “rating of perceived exertion”, specifically anchored to reps in reserve. Each value maps cleanly:
| RPE | Reps left | What the set felt like |
|---|---|---|
| 10 | 0 | True failure, no more reps possible |
| 9 | 1 | Could grind one more |
| 8 | 2 | Two clean reps left |
| 7 | 3 | Three reps left, smooth |
| 6 | 4 | Four reps left, easy working set |
The 0.5 increments (8.5, 9.5) capture sets between integer values, where the lifter can’t tell exactly how many reps were left.
Worked example
A lifter benches 100 kg × 5 reps. They report it felt like RPE 8.
That tells the coach two things:
- The set was hard but not maximum effort (2 reps in reserve)
- The lifter could have done 7 reps total at this load
Using the Tuchscherer RTS table, 5 reps at RPE 8 maps to 81.1% of 1RM. So the estimated 1RM is:
1RM = 100 / 0.811 = 123.3 kg
If the lifter reports the same set felt like RPE 9 (only 1 in reserve), the estimated 1RM is 100 / 0.837 = 119.5 kg. One RPE point shifts the estimate by 3.8 kg. That’s why honest RPE rating matters. Small differences in the rating produce real differences in subsequent prescriptions.
RPE vs RIR
RPE 10 = RIR 0. RPE 9 = RIR 1. RPE 8 = RIR 2. They’re the same number, two phrasings.
RPE (“how hard did this feel?”) works best for trained lifters who’ve internalised the scale. RIR (“how many more reps could you have done?”) works better for novices because it’s a concrete count rather than a feeling rating.
The full breakdown of when to use each is in the RPE vs RIR guide.
How RPE drives autoregulation
RPE prescriptions adjust load to readiness automatically. The program tells the lifter “do 5 reps at RPE 8”. On a fresh day, that’s 82 kg. On a tired day, that’s 78 kg. The lifter picks the load that hits the prescribed feeling, instead of forcing a fixed percentage that may overshoot or undershoot today’s actual capacity.
This is the foundation of autoregulation.
What RPE doesn’t measure
RPE captures effort relative to maximum possible effort on that lift, on that day. It doesn’t capture:
- Muscle damage or DOMS (you can hit RPE 10 and feel fresh tomorrow, or RPE 6 and be wrecked)
- Cardiovascular load (a heavy single is RPE 10 anaerobically but doesn’t elevate heart rate much; AMRAPs do the opposite)
- Technical risk (a sloppy RPE 8 with form breakdown isn’t safer than a clean RPE 9)
For tracking recovery, use sleep + soreness + readiness scores separately.
Common confusion
“My RPE 8 felt different last week.” Normal. RPE adjusts for daily readiness. That’s the point. Same prescribed RPE on a tired day means lower load. The autoregulation is working.
“What about RPE 11 or 12?” No such thing. The scale tops out at 10 (true failure). Sets pushed past failure (forced reps, rest-pause) get separate annotations, not extended RPE.
“My set was RPE 8 but I missed the last rep.” Then it was RPE 9.5 or 10. RPE measures what happened, not what was prescribed.
In Coach Sheet
The Workout Plan tab uses RPE in three columns: Prescribed RPE (what the coach planned), Achieved RPE (what the lifter rated after lifting), and Load (the actual weight used). Save Week reads Achieved RPE to decide next week’s load progression. RPE 9-10 hits target = hold load; RPE 7-8 = +2.5 kg main lift; RPE ≤6 with target exceeded = +5 kg main lift.
The RPE calculator gives starting load suggestions for any (reps, RPE) combination. The 3-test PR protocol calibrates the lookup table to the specific lifter over 6-9 weeks.
Sources
- [1]
- [2]