Association between isokinetic strength measures and functional performance in community-dwelling older adults

Abstract

ABSTRACT Previous studies have shown an association between lower limb muscle strength and functional performance, but a dose-response relationship between the strength of each lower limb muscle group and performance in daily life activities in older adults has not been well established. Thus, this study aimed to investigate the association between isokinetic muscle strength of all eight major lower limb muscle groups and functional performance in community-dwelling older adults. The muscle strength of the plantar flexors and dorsiflexors of the ankle, flexors and extensors of the knee, and flexors, extensors, adductors, and abductors of the hip were evaluated using a Biodex System 4 Pro® isokinetic dynamometer. Functional performance was evaluated in 109 participants using the five-times sit-to-stand test (STS) and 4-meter usual walking speed (UWS). The multiple linear regression analyses showed that the hip abductors strength predicted 31.3% of the variability for UWS (p=0.011), and the knee extensors strength (p=0.015) predicted 31.6% of the variability for the STS. We conclude that hip abductors and knee extensors could be the key muscle groups involved in sit to stand and walking speed performance in older adults.