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The system
Article 02 · The system

What is RPE?

RPE stands for Rate of Perceived Exertion — a 1-to-10 scale of how hard a set or session felt to you. It’s the most reliable real-time signal of training stress because it captures fatigue, sleep, life stress, and execution quality that weight-on-the-bar can’t.

The scale
RPE 6 — comfortable, 4 reps left. Easy day pace.
RPE 7 — moderate, 3 reps left. Most working sets.
RPE 8 — hard, 2 reps left. Top sets at intensity.
RPE 9 — very hard, 1 rep left. Peaking, testing.
RPE 10 — true max, no reps left. Rare.

You log RPE per set in the strength logger and once per session at completion. Half-points (7.5, 8.5) are accepted. Be honest — the AI uses RPE drift to decide whether to push, hold, or back off next week.

Related
What the AI reads when building next weekEvery input below feeds into next week’s rebuild. Logs, RPE, feedback chips, notes, synced activities, off-program activities, and every Settings input.Per-session feedback chipsTap-to-select chips at session completion. Each chip is a structured signal the AI can act on next week — “weights too light” on Tuesday means heavier Tuesday next week.
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