RPE — rate of perceived exertion — is simply how hard an effort feels, on a scale of 1 to 10. It sounds unscientific, but it is one of the most useful tools in hybrid training.
The scale
- 1–2: Very easy. Walking.
- 3–4: Easy. Conversational.
- 5–6: Moderate. Talking gets harder.
- 7–8: Hard. A few words.
- 9: Very hard. Nearly all-out.
- 10: Maximum.
When RPE beats heart rate
- Short efforts: heart rate lags behind.
- Stations: wrist monitors struggle with strength movements.
- Heat, stress or poor sleep: heart rate is raised, but you still need to train by how hard you are actually working.
- Strength training: RPE, or reps in reserve, helps you choose the right weight.
Calibrating it
RPE works best when you compare it with something measurable at first. Do a threshold run and note how it feels. Over time, you learn what each level feels like.
Using RPE in sessions
- Easy runs: RPE 3–4.
- Threshold runs: RPE 7.
- Hard intervals: RPE 8–9.
- Strength: stop sets at RPE 8, one or two reps short of failure.
Race day
Pacing a race by RPE is common. Early in the race, it will feel easier than it is. Aim for an RPE a notch lower than you think early on.