Context:
A strength-endurance diagram predicts that a person should be able to perform 30 repetitions of an exercise if the resistance level is 60% of 1-repetition maximum (1RM).
Objective:
To compare the number of repetitions predicted by the diagram with recorded repetitions of a shoulder exercise.
Design:
Single-group comparison with a standard.
Setting:
University.
Participants:
34 healthy adults (20 women, 14 men) with a mean age of 29 years (range 20–49).
Main Outcome Measures:
The number of repetitions that subjects could perform in good form of a shoulder exercise with resistance of 60% 1RM.
Results:
The mean number of repetitions was 21 (± 3, range 15–28), which was significantly different than the 30 repetitions that the diagram predicted.
Conclusions:
The strength-endurance diagram did not accurately predict the number of repetitions of a shoulder exercise that subjects could perform.
