Influence of between‐limb asymmetry in muscle mass, strength, and power on functional capacity in healthy older adults

Purpose Numerous daily tasks such as walking and rising from a chair involve bilateral lower limb movements. During such tasks, lower extremity function (LEF) may be compromised among older adults. LEF may be further impaired due to high degrees of between‐limb asymmetry. The present study investigated the prevalence of between‐limb asymmetry in muscle mass, strength, and power in a cohort of healthy older adults and examined the influence of between‐limb asymmetry on LEF. Methods Two hundred and eight healthy older adults (mean age 70.2 ± 3.9 years) were tested for LEF (400 m walking and 30‐seconds chair stand). Furthermore, maximal isometric and dynamic knee extensor strength, leg extensor power, and lower limb lean tissue mass (LTM) were obtained unilaterally. Results Mean between‐limb asymmetry in maximal muscle strength and power ranged between 10% and 13%, whereas LTM asymmetry was 3 ± 2.3%. Asymmetry in dynamic knee extensor strength was larger for women compared with men (15.0 ± 11.8% vs 11.1 ± 9.5%; P = .005) Leg strength and power were positively correlated with LEF (r2 = .43‐.46, P