Objectives: To determine the 1-week test-retest reliability of stationary dynamometer scores in the measurement of muscle strength in older adults and to determine the reliability of composite scores obtained by combining right and left lower limb strength scores for each muscle group.
Design: In separate sessions, 1 therapist performed repeated measurements of muscle force production.
Setting: Outpatient physical therapy clinic of a large teaching hospital.
Participants: A convenience sample of 25 volunteers aged 70 to 87 years residing independently in the community and who did not have significant health problems.
Intervention: On 2 separate occasions, 1 week apart, bilateral isometric force measurements were obtained for the flexor and extensor muscle groups of the ankle, knee, and hip joints.
Main outcome measures: For test-retest reliability of individual and composite scores, the intraclass correlation coefficients (ICCs) and 90% confidence intervals were determined.
Results: The mean scores for ankle dorsiflexion, knee flexion and extension, and hip flexion exhibited excellent reliability with ICCs ranging from.90 to.76 for the individual lower limb scores and.91 to.84 for the composite scores. Scores for the remaining muscle groups exhibited good reliability with ICCs ranging from.74 to.71 for the composite scores.
Conclusion: The stationary dynamometer is a reliable tool to use in determining lower limb muscle force production in elderly adults.