Rate of Perceived Exertion (RPE)
RPE stands for Rate of Perceived Exertion — a subjective scale for measuring how hard you feel you're working during exercise.
The most common version is the 1–10 scale (or sometimes 6–20, the original Borg scale).
1–10 RPE:
- 1–2: Barely moving, very easy
- 3–4: Easy, conversational, warm-up pace
- 5–6: Moderate effort, can speak in short sentences
- 7–8: Hard, breathing heavy, hard to talk
- 9: Very hard, can only say a few words
- 10: Maximum effort, unsustainable
RPE lets you regulate intensity without obsessing over pace or heart rate — useful on hilly terrain, hot days, or when you're fatigued, where the same pace feels much harder.