Gender and age-related differences of dynamic balancing ability based on various stepping motions in the healthy elderly.

This study was aimed at examining the gender and age-related differences of dynamic balance based on four stepping tests for the elderly. One hundred and eleven healthy subjects aged 60-85 were classified into four age groups (60-64, 65-69, 70-74, and 75-85) to examine age-related differences. They conducted stepping motions lasting 20-sec, including both-leg stepping right/left, both-leg stepping back/forth, one-leg stepping back/forth and one-leg stepping right/left. There were significant differences by age in all stepping parameters, with the decreasing number of steps and the increasing average ground connecting time during stepping with age. In males of age 60-69 and all females, the individual differences in the number of steps and the average connecting time during both-leg stepping (back/forth and right/left) were larger than those during one-leg stepping. Both-leg stepping was, therefore, considered to be a useful test to evaluate the individual differences of dynamic balance in the elderly. Individual differences in the number of steps by both-leg stepping tended to decrease with age. In males aged 70 or more, the individual differences in the number of steps and the average connecting time in both-leg stepping were smaller than those in one-leg stepping. The relationships between the results by both-leg stepping and those by one-leg stepping were poor. This may be because of the difference in body-posture stability during stepping motions. One-leg stepping is a useful test for the elderly who have difficulty with both-leg stepping because of its small center of gravity sway. The relationships between back/forth steps and right/left steps in both-leg or one-leg stepping were notable. Either of the stepping motions, therefore, can be selected to evaluate dynamic balance ability. There may be gender differences in the strategy to keep a stable body posture during both-leg stepping.