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One rep max (1RM)

Seven formulas, a percentage table and working weights for any rep range

Formula and method

Epley: weight × (1 + reps ÷ 30). Brzycki: weight × 36 ÷ (37 − reps). The others follow a similar shape but behave differently at high rep counts, which is why the headline figure is an average.

Sources

  • Epley B. Poundage chart. Boyd Epley Workout, 1985.
  • Brzycki M. Strength testing: predicting a one-rep max from reps to fatigue. JOPERD, 1993.

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