Measurement of hip extension strength with a portable device: Description, reliability and validity of a procedure

Although adequate hip extension strength is necessary for the successful performance of weight-bearing activities, practical quantitative procedures for measuring hip extension strength are lacking. We sought, therefore, to describe a practical procedure and the reliability and validity of measurements obtained with it. Apparently healthy individuals (10 men, 10 women) of 18-27 years participated. One male and one female examiner tested all subjects in supine with a hand-held dynamometer during 2 sessions, 1 week apart. Inter-tester and test-retest reliability of measurements were good to excellent (intraclass correlation coefficients = 0.827-0.949). Known groups validity was supported by a demonstration of significant differences in the strength of men and women participants. Based on the findings of this study we can recommend the procedure for testing with other populations.