Variability in human locomotion: are repeat trials necessary?

This study proposed to determine the extent to which multiple gait trials provide further information than that obtained from a single trial of walking. Gait data were collected using a video camera and force platform system on 10 subjects including a below knee amputee. The data supported several conclusions. If the purpose of gait research is to investigate and detail the kinematic and kinetic patterns of individual subjects, either during a single data collection session or across several sessions, then recording a single stride of normal gait per subject can be justified. However, if the purpose of the research is to produce population norms, then multiple strides per subject are necessary to obtain estimates of variability.