Article

The mechanisms regulating the bilateral coordination of gait in humans are
largely unknown. Our objective was to study how bilateral coordination changes as
a result of gait speed modifications during over ground walking. 15 young adults
wore force sensitive insoles that measured vertical forces used to determine the
timing of the gait cycle events under three walking conditions (i.e.,
usual-walking, fast and slow). Ground reaction force impact (GRFI) associated
with heel-strikes was also quantified, representing the potential contribution of
sensory feedback to the regulation of gait. Gait asymmetry (GA) was quantified
based on the differences between right and left swing times and the bilateral
coordination of gait was assessed using the phase coordination index (PCI), a
metric that quantifies the consistency and accuracy of the anti-phase stepping
pattern. GA was preserved in the three different gait speeds. PCI was higher
(reduced coordination) in the slow gait condition, compared to usual-walking
(3.51% vs. 2.47%, respectively, p=0.002), but was not significantly affected in
the fast condition. GRFI values were lower in the slow walking as compared to
usual-walking and higher in the fast walking condition (p<0.001). Stepwise
regression revealed that slow gait related changes in PCI were not associated
with the slow gait related changes in GRFI. The present findings suggest that
left-right anti-phase stepping is similar in normal and fast walking, but altered
during slow walking. This behavior might reflect a relative increase in attention
resources required to regulate a slow gait speed, consistent with the possibility
that cortical function and supraspinal input influences the bilateral
coordination of gait.
CI - Copyright (c) 2013 Elsevier B.V. All rights reserved.

Langue : ANGLAIS