Association between physical performance and muscle strength among elderly

Abstract

Aim: Studies about the relationships between muscle mass, muscle strength and physical performance in Egyptian elderly are scarce.The current study aimed to investigate the relationships between muscle mass, muscle strength and physical performance in a sample of older Egyptians. Methods: The study was a case-control study conducted on 76 elderly subjects, aged from 60 -75 years old,males and females,recruited from geriatric outpatient clinic, Ain Shams University hospital. Subjects were divided according to gait speed ( measured by four meters walking test)as indicator of physical performance into two groups,cases:38 subjects withlow gait speed (<0.8 m/s),and controls: 38 subjects with normal gait speed (≥0.8 m/s).Appendicular skeletal mass (ASM) was measured by dual-energy X-ray absorptiometry andskeletal muscle index (SMI) was calculated ,whereas, grip strength was measured by dynamometer(Jamar Hydraulic hand dynamometer)for all participants Results: Muscle mass was not significantly different between the two groups whereas, Muscle strength was significantly lower in subjects with impaired physical performance measured by gait speed(89%,p=<0.01).There was a significant inverse correlations between muscle strength, height and the gait speed in seconds (p=<0.01,p=<0.05) respectively. Low muscle strength and advanced age were significant independent predictors of low gait speed among studied population. Conclusion: Muscle strength has greater effect on physical performance than muscle mass among elderly subjects. Programs that target muscle strength can have great impact on the physicalfunction and quality of life of the elderly.