Article

OBJECTIVES: To examine the effects of walking on a treadmill at varying gradients
and speeds on ankle muscle activation in stroke survivors, and to compare the
effect of increasing speed on plantarflexor muscle activity in participants
grouped according to spasticity severity. DESIGN: Within-subject and
cross-sectional design. Participants walked on a standard treadmill at 3
different inclines (0 degrees ,
3 degrees , 6 degrees ) and speeds
(self-selected, self-selected+20%, self selected+40%). SETTING: University
laboratory. PARTICIPANTS: A convenience sample of stroke survivors (N=19; 13 men,
6 women) available in university clinics. INTERVENTIONS: Not applicable. MAIN
OUTCOME MEASURES: Electromyographic activity of medial gastrocnemius (MG) and
tibialis anterior (TA) muscles at push-off phase of the gait. RESULTS: Paretic MG
muscle activity increased (but TA did not change) at faster speeds irrespective
of the incline (P<.05). In contrast, MG muscle activity increased at a higher
incline in the nonparetic side (P<.05), but not in the paretic side (P>.05). In
the high-spasticity subgroup (Tardieu Scale >/=2), paretic MG activity increased
as walking speed increased (P=.004). CONCLUSIONS: Stroke survivors appear to use
distinct muscle activation strategies on the paretic and nonparetic sides in
response to different walking speeds and inclines. Our data indicates that
individuals with stroke can be safely trained on a treadmill to walk 20% to 40%
above the self-selected pace to improve MG output without adversely affecting TA
output. The speed-dependent characteristic of spasticity may help generate
greater MG activity during push-off.
CI - Copyright (c) 2016 American Congress of Rehabilitation Medicine. Published by
Elsevier Inc. All rights reserved.

Langue : ANGLAIS