Inclusion Criteria1. Ischemic or hemorrphagic stroke with drop foot problem.
2. Sufficient cognition to follow simple instructions and to understand the content and purpose of the study. (Mini-Mental State Examination > 20)
3. Capable of standing and walking independently for an extended period of time. (Functional Ambulation Category > 3, Berg Balance Scale > 40)
Exclusion Criteria1. Any medical or psychological dysfunctions that would affect their ability to comply with test study protocol, such as lower back pain, neuralgia, rotational vertigo, muscloskeletal disorders, injuries, and pregnancy.
2. Any severe contractures in hip, knee, or ankle joint that would preclude passive range of motion in the lower extremity.
3. Participation in any therapeutic treatment ("outside therapy") performed with the lower extremity during the planned study, including the baseline and the followup.