Age-Related Changes in Dynamic Balance Ability in the Stepping Test and Force-Generating Capacity of the Lower Limb Muscles

Background : This study examined the relationship between two abilities in terms of age-related changes, namely, the dynamic balance ability and the force-generating capacity of the three lower limb joints. Methods : A group of 149 middle-aged to older adults (38 men and 111 women aged 74.1 ± 11.6 years) had their dynamic balance ability and the force-generating capacity of their three lower limb joints measured in the stepping test and the chair sit-to-stand test, respectively. The number of steps, the double-leg support time, and the single-leg support time were evaluated to show dynamic balance ability in the step test. The peak reaction force per body weight (F/w) and rate of force development were evaluated for the force-generating capacity of the three lower limb joints. Results : The results showed that none of the parameters of dynamic balance ability in the stepping test had any age-related changes, but F/w and rate of force development showed age-related changes, decreasing with age. Conclusion : No association was seen between dynamic balance ability in the stepping test and the force-generating capacity of three lower limb joints. Significance : Age-related changes in dynamic balance do not correspond to changes in muscle strength, suggesting that evaluating dynamic balance ability solely through the stepping test at a self-selected speed may be challenging.