Brzycki used a simple linear equation to predict the one repetition maximum (1-RM) bench pressing weight based on the number of repetitive lifts until failure using a certain weight.



(1) The person warms up thoroughly with light weights, calisthenics and stretching exercises.

(2) A weight is selected that is expected to result in failure with 9 or fewer (less than 10) repetitions.

(3) The reps are performed in a slow, continuous manner with no more than 2 seconds rest between lifts.

(4) If the person reps to failure within 9 repetitions, then calculate the predicted 1 repetition maximum.

(5) If the person does not rep to failure within the 9 repetition range, let the person recover then try with a lighter or heavier weight as needed.


percent of 1 repetition maximum (as a number from 0 to 100) =

= 102.78 - (2.78 * (number of repetitions with that weight))


predicted 1 repetition maximum =

= (weight used for repetition) * 100 / (percent of 1 RM) =

= (weight used for repetition) / (1.0278 - (0.0278 * (number of repetitions with weight)))



• Strict adherence to the protocol is required to achieve consistent results.

• Mayhew et al (1993, Table 2 page 36) and Chapman et al (1998) showed that the accuracy declined with higher numbers of repetitions, starting around 10 repetitions.


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