One‑Rep Max (1RM) — Quick 8-Section Guide
1) Core idea
1RM is the heaviest weight you can lift once with good form. We estimate it from submax sets using validated formulas.
2) Flow you can trust
- Enter weight, reps, and choose a formula or “Average”.
- Optionally add RPE to autoregulate (+% if reps in reserve).
- See training percentages and zones built from the estimate.
3) Sanity checks
- Best accuracy in the 2–10 rep range.
- Technique breakdown inflates estimates—use clean reps.
4) Shortcuts
- No preference? Use “Average” across Epley, Brzycki, Lander, Lombardi, Mayhew, O’Conner, Wathan.
- Hypertrophy work: 65–80% 1RM; Strength: 80–90% 1RM.
5) Pitfalls
- Using high‑rep sets (>10) for 1RM extrapolation.
- Programming from an outdated 1RM; update every 4–8 weeks.
6) Micro examples
- 100 kg × 5 reps (RPE 9) → Epley ≈ 116.7; with +3% ≈ 120.2 kg.
- 80 kg × 10 reps (RPE 8) → Average ≈ mid‑100s depending on formula.
7) Mini‑FAQ
- Which is “most accurate”? Depends on lift and rep range; averaging reduces bias.
- Use kg or lb? Either—display matches your unit selection.
8) Action tip
Set top sets by RPE and back‑offs by % of the calculated 1RM for a balanced, autoregulated plan.