Effects of different walking speed on ankle muscle onset timing in middle-aged healthy adults

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 and decreasing walking speed. This study has examined the effects of walking on a treadmill at varying gradients and speeds on ankle muscle timing in healthy middle-aged adults.
Fifteen healthy middle-aged adults (10M/5F; average age 56.53±7.20 years; body mass index 28.52±3.70 kg/m2) participated in the study. Participants walked on a standard treadmill at three different walking speeds (self-selected, self-selected%, self-selected%) and positive inclines (0°, 3°, and 6°). The onset muscle timing of MedialGastrocnemius (MG), and Tibialis Anterior (TA) muscles recorded at push off phase of the gait.
A linear mixed model (LMM) regression analysis was used to analysis. The onset of MG and TA muscles activity delayed at faster speeds on the nonodominant side (p0.05).
Data showed that there is a bias towards using dominant side to overcome challenging walking conditions in middle-aged adults.