Comparison of stepping parameters and center of foot pressure properties during different tempo stepping movements

Abstract

This study was designed to examine the trial-to-trial reliability of stepping parameters and to compare the center of foot pressure (COP) when adapting to different tempos. Twenty healthy men (M age = 20.8, SD = 1.9 years) performed stepping tests to fixed tempos. The intra-class correlation coefficients of stepping and COP parameters were high (0.75 - 0.97). The time difference between foot contact time and fixed tempo and COP sway velocities of the X- and Y-axis were the largest at 40 beats per minute (bpm). At 60 and 120 bpm tempos, single support and swing times reflecting the stepping strategy correlated significantly with the root mean square and the velocity of the X-axis (r = I0.45 - 0.53I) . Because these step tempos are controlled largely by the automation of stepping, the single support and swing phases appeared to have a constant frequency. On the other hand, a stepping tempo of 40 bpm showed the largest sway velocity of X and Y and the smallest surrounding area mean path length. The above suggests that stepping at 40 bpm induced a larger sway area in relation to total path length and faster COP sway. Hence, it is inferred that the stepping task becomes more difficult at 40 bpm than at 60 and 120 bpm.