Article

This work sought to advance the understanding of dynamic stability control during
stepping. The specific intention was to better understand the control of the
centre of mass during voluntary stepping, by characterizing its trajectory and
intertrial variability. Young participants (n=10) performed five different
stepping tasks to vary the challenge to COM control: (1) preferred step, (2) long
step, (3) wide step, (4) long and wide step and (5) rapid step. The trajectory of
the total body COM during the restabilisation phase was assessed by quantifying
the magnitude of incongruity between the peak and final COM position. The
intertrial variability of incongruity and the extent to which incongruity was
reduced with trial repetition were also evaluated. Interestingly, incongruity was
typical during preferred stepping, with a strong bias toward overshoot. In the
frontal plane, the magnitude of incongruity and the incidence of overshoot were
greater in trials with increased step width. The variability of incongruity did
not vary by condition nor was there evidence of adaptive changes. Together, these
results suggest that overshoots may represent a strategy linked to gait
initiation or to the simplification of reactive control during the
restabilisation phase. Further insight into these mechanisms will be gained by
examining the kinetic determinants of dynamic stability control.
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Langue : ANGLAIS