Effects of treadmill grade and speed on medial gastrocnemius muscle activity in chronic stroke patients

Plantarflexor muscles produce propulsive force in the second half of stance phase; deficient motor output from these muscles would lead to inadequate propulsion at push off phase of gait following stroke. It is important to develop strategies to improve plantarflexor output. This study examined the effects of walking on a treadmill at varying gradients and speeds on medial gastrocnemius (MG) muscle activation in stroke survivors.
Nineteen stroke survivors (13M/6F: average age 55.37±7.54 years; body mass index 29.10±4.52kg/m2) participated in the study. Participants walked on a standard treadmill at three different positive inclines (0°, 3°, and 6°) and speeds (self-selected, self-selected%, self-selected%). The electromyographic activity of MG recorded at push off phase of the gait.
A linear mixed model regression analysis was used to analysis. The paretic MG muscle activity increased at faster speeds irrespective of incline (p0.05).
It would appear that stroke survivors employ distinct muscle activation strategies on the paretic and non-paretic sides in response to different walking speeds and inclines