Procedure:
(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)))
Limitations:
• 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.
