The purpose of this study is to examine the reflex excitability of the rectus femoris in individuals with and without post-stroke Stiff-Knee gait. We use electrical stimulation of the peripheral nerve innervating the rectus femoris for a well-controlled reflex stimulus. We are investigating whether reflex excitability of the rectus femoris correlates with gait kinematics.

The purpose of this study is to investigate the role of hyperreflexia in post-stroke Stiff-Knee gait function. In one aim,

Inclusion criteria:

• Aged at least 18
• Premorbidly independent
• If post-stroke, mild to moderate impairment determined by standard practices per the physical therapist
• Able to continuously walk for 30 minutes
• If post-stroke, reduced knee flexion during walking relative to unimpaired side
• If post-stroke, hemiparesis
• Ability to provide informed consent

Exclusion criteria:

• No history of serious lower limb musculoskeletal injury
• No functionally relevant osteoarthritis and weight-bearing restrictions
• No functionally relevant polyneuropathy
• No functionally relevant cognitive impairment
• No functionally relevant vision impairment