Muscle force measured using "break" testing with a hand-held myometer in normal subjects aged 20 to 69 years

Objective: To measure the strength of 17 muscle groups in the upper and lower extremities in a large group of healthy subjects using "break" testing with a hand-held myometer, and to examine the intrasession and intersession reliability of the testing protocol. Subjects and Instrumentation: A convenience sample of 20 men and 20 women in each decade of age from 20 to 69 years (n = 200) was tested using a Penny & Giles hand-held myometer. Results: Reliability coefficients were >.85 for both intrasession and intersession reliability, except for the ankle dorsiflexors. Men exerted a significantly greater force than women for all muscle groups. Age, weight, and side of testing were significant predictors of force in the majority of muscle groups. The fifth percentile values, as the lower limit of normal, are reported separately for gender and side of testing for each decade of age. Conclusion: Using the testing protocol specified in this study, data from patients with various neuromuscular diseases may be compared with the appropriate gender- and age-matched normal data to accurately identify the presence of weakness.