One Rep Max (1RM) Epley & Brzycki
Estimate max single lift from submaximal weight and reps. Average Epley and Brzycki for stability, cap reps 1-12. Table gives rep percentages for programming.
TL;DR
- Epley w×(1+r/30), Brzycki w×36/(37-r)
- Formulas: Epley: w×(1+r/30) | Brzycki: w×36/(37-r)
- 80kg×6
How it works
Epley w×(1+r/30), Brzycki w×36/(37-r). Average them; beyond 10 reps noise increases. Table backs down ~3-4% per rep.
The math
80kg×6 →Epley96, Brzycki94.7 avg95.4. 5RM≈83. Inverse: weight≈1RM/(1+reps/30).
Average for robustness; cap 12 reps.
Examples
80kg×6
- Avg 95.4
- 5RM 83
100kg×3
- Avg 110
When to use it
✦ Programming
Set loads without max test.
✦ Tracking
Progress without injury.
⚠ Common mistakes
- Testing true 1RM weekly
- Using >10 reps for estimate
FAQ (6)
Epley or Brzycki?
We show both and average. Epley is conservative for high reps, Brzycki aligns better for strength ranges 1-6.
Can I get reps from 1RM?
Yes, reverse: weight ≈ 1RM / (1+reps/30) for planning sets.
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