Title : NEUROMUSCULAR STRATEGIES IN THE PARETIC LEG DURING CURVED 1 WALKING IN INDIVIDUALS

20 Reduced flexibility over the neuromotor control of paretic leg muscles may impact 21 the extent to which individuals post-stroke modulate their muscle activity patterns to 22 walk along curved paths. The purpose of this study was to compare lower limb 23 movements and neuromuscular strategies in the paretic leg of individuals with stroke to 24 age-matched controls during curved walking. Participants walked at their preferred 25 walking velocity along four different paths of increasing curvature while lower limb 26 kinematics and muscle activity were recorded. A second group of able-bodied 27 individuals walked along the four paths matching the walking speed of the stroke group. 28 The stroke group showed reduced lower limb joint excursion and disordered modulation 29 of foot pressure during curved walking, accompanied by reduced modulation of muscle 30 activity patterns. In the controls, the postero-medial (medial gastrocnemius and medial 31 hamstring) muscles of the inner leg of the curved showed decreasing EMG amplitude 32 as path curvature increased. Conversely, activity of the postero-lateral musculature of 33 the outer leg was dcreased with increasing path curvature. Activity in the tibialis anterior 34 and gluteus medius were also modulated with path curvature. However, in the stroke 35 group, we found reduced modulation of muscle activity in the paretic leg during curved 36 walking. The extent of modulation was also associated with the level of physical 37 impairment due to stroke. The results of this study provide further knowledge about 38 neuromuscular control of locomotor adaptations post-stroke. 39