Abstract
This study was carried out in order to compare stride time (gait) variability of walking not only between young and older adults, but also between “fallers” and “non-fallers”. Moreover, this study aimed to clarify the relationship between stride time variability, balance ability, muscular strength and fall experience. The subjects were 12 young women aged 21.2±2.2 years (young group) and 27 older women aged 66.6±4.4 years (older group). The older group included 14 fallers and 13 non-fallers. They wore an accelerometer on their back and walked at a slow, preferred or fast pace. The time of heel contact was detected by acceleration waveform, and stride time was estimated. The stride time variability was computed by the coefficient of variance (CV) of stride time. The subjects underwent balance tests and muscular strength tests. The CV of stride time at the preferred and fast pace were significantly larger in the older group than in the young group, even though there was no difference in any of the gait speeds between the two. The CV of stride time was significantly larger in fallers than in non-fallers at the fast pace. Path analysis showed that fall experience was affected by an increase in the CV of stride time and decreased balance ability, but less affected by decreased muscular strength. Therefore, this study suggested that stride time variability when walking fast is useful as an early assessment of fall risk in middle-aged and elderly people and that fall experience was affected by stride time variability and balance ability.
