DISCUSSION
We investigated the kinematic characteristics of gait
among healthy middle-aged, older and young age groups
during their level walking. Compared with young and older
subjects, middle-aged adults showed no significant difference
in temporal-spatial gait parameters. By measuring the gait
stability parameters, middle-aged subjects showed a similar
degenerated pattern of gait stability as the older ones in ML
direction, which is scarcely reported in previous studies.