Article

Increased respiration in chronic obstructive pulmonary disease (COPD) requires
greater abdominal muscle activation, which may impact on contribution of the
trunk to postural control. This study aimed to determine whether recovery of
balance from postural perturbations and trunk muscle activity differs in people
with and without COPD before and/or after exercise. Electromyography (EMG) of the
obliquus internus (OI) and externus (OE) abdominis, rectus abdominis (RA),
erector spinae (ES) and deltoid muscles was recorded with surface electrodes
during rapid shoulder flexion and extension. Time taken to regain baseline centre
of pressure velocity (vCOP) and the number of postural adjustments following arm
movement was calculated from force plate data. Time to recover balance in the
direction of postural disturbance (anteroposterior vCOP) was longer in COPD,
particularly more severe COPD, than controls. Mediolateral vCOP (perpendicular to
the perturbation) and the number of postural adjustments did not differ between
groups, but people with more severe COPD were less successful at returning their
mediolateral vCOP to baseline. Abdominal muscle EMG was similar between groups,
but controls had greater ES EMG during arm movements. Individuals with more
severe COPD had greater OE and RA EMG both before and during arm movement
compared to those with less severe COPD and controls. Following exercise, OE and
ES EMG increased in people with less severe COPD.
This study shows that severe
COPD is associated with impaired ability to recover balance and greater trunk
muscle activity during postural challenges. Augmented trunk muscle activity may
limit the contribution of trunk movements to balance recovery and could
contribute to increased falls risk.
CI - Copyright (c) 2015 Elsevier B.V. All rights reserved.

Langue : ANGLAIS