Strength Training
Brzycki one rep max estimate
A ratio rather than a linear factor. Because the denominator shrinks as reps rise, it diverges from Epley at higher rep counts, which is why the two rarely agree.
The Formula
1RM = w x 36 / (37 - reps)
A ratio rather than a linear factor. Because the denominator shrinks as reps rise, it diverges from Epley at higher rep counts, which is why the two rarely agree.
| Symbol | Meaning | Unit | Notes |
|---|---|---|---|
| w | Weight lifted | kg or lb | The same input as the Epley form; the formulas differ only in shape. |
| reps | Repetitions completed | reps | As reps approach thirty-seven the denominator approaches zero, so the formula is only sensible at low rep counts. |
What Each Symbol Means
wkg or lb
Weight lifted
The same input as the Epley form; the formulas differ only in shape.
repsreps
Repetitions completed
As reps approach thirty-seven the denominator approaches zero, so the formula is only sensible at low rep counts.
See It Worked With Real Numbers
A formula on its own does not tell you which number goes where. The how to calculate one rep max page applies this equation to a concrete case, shows every intermediate step, and names the mistakes that produce a wrong answer even when the algebra is right.
Where This Formula Appears
This equation is the working core of How To Calculate One Rep Max, filed under Health. Every number the guide produces comes from substituting into this one line.