The One Rep Max (1RM) is the maximum weight a person can lift for a single repetition with proper form. It is the gold standard for measuring strength and programming percentage-based training.
1RM = weight × (1 + reps / 30)
Developed by Boyd Epley in the 1980s, this formula is widely used because of its simplicity and reasonable accuracy across different rep ranges.
1RM = weight × (36 / (37 - reps))
Created by Matt Brzycki, this formula tends to be more accurate at lower rep ranges (1-6 reps) but can overestimate at higher rep ranges.
Taking the average of Epley and Brzycki provides the most accurate estimate by canceling out each formula's biases across different rep ranges.
Safety Disclaimer: Testing your true 1RM carries risk of injury. Use these estimates for programming instead of testing maxes directly unless you are an experienced lifter with proper supervision.
Calculate your one-rep max (1RM) using the Epley and Brzycki formulas. Generate a percentage-based training table for strength programming.
Optimal range: 1-10 reps for accuracy
Estimated 1RM
114.6kg
Training Percentage Table
Results are estimates based on standard models. Please verify critical data before taking action. Terms of Use
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