Impaired regulation post-stroke of motor unit firing behavior during volitional relaxation of knee extensor torque assessed using high density surface EMG decomposition.

The purpose of this study was to use high density surface EMG recordings to quantify stroke-related abnormalities in motor unit firing behavior during repeated sub-maximal knee extensor contractions. A high density surface EMG system (sEMG) was used to record and extract single motor unit firing behavior in the vastus lateralis muscle of 6 individuals with chronic stroke and 8 controls during repeated sub-maximal isometric knee extension contractions. Paretic motor unit firing rates were increased with subsequent contractions (6.

The stroke-related effects of hip flexion fatigue on over ground walking.

Individuals post stroke often rely more on hip flexors for limb advancement during walking due to distal weakness but the effects of muscle fatigue in this group is not known. The purpose of this study was to quantify how stroke affects the influence of hip flexor fatigue on over ground walking kinematics and performance and muscle activation. Ten individuals with chronic stroke and 10 without stroke (controls) participated in the study.