Article

There are many everyday situations in which a supportive hand contact is required
for an individual to counteract various postural perturbations. By emulating
situations when balance of an individual is challenged, we examined functional
role of supportive hand contact at different locations where balance of an
individual was perturbed by translational perturbations of the support surface.
We examined the effects of handle location, perturbation direction and
perturbation intensity on the postural control and the forces generated in the
handle. There were significantly larger centre-of-pressure (CoP) displacements
for perturbations in posterior direction than for perturbations in anterior
direction. Besides, the perturbation intensity significantly affected the peak
CoP displacement in both perturbation directions. However, the position of the
handle had no effects on the peak CoP displacement. On the contrary, there were
significant effects of perturbation direction, perturbation intensity and handle
position on the maximal force in the handle. The effect of the handle position
was significant for the perturbations in posterior direction where the lowest
maximal forces were recorded in the handle located at the shoulder height. They
were comparable to the forces in the handle at eye height and significantly lower
than the forces in the handle located either lower or further away from the
shoulder. In summary, our results indicate that although the location of a
supportive hand contact has no effect on the peak CoP displacement of healthy
individuals, it affects the forces that an individual needs to exert on the
handle in order to counteract support perturbations.
CI - Copyright (c) 2014 Elsevier B.V. All rights reserved.

Langue : ANGLAIS