CUped: An Approach to Motor Recovery Post-Stroke, Not Compensation

Inclusion Criteria: * Single, unilateral stroke in adulthood. * Cortical, subcortical stroke. Individuals with cortical lesions affecting sensory and motor structures in the gray matter of the brain will be included. Individuals subcortical white matter lesions affecting the internal capsule and corona radiata will be included. * Ischemic, hemorrhagic stroke. Individuals with ischemic and hemorrhagic strokes will be admitted. Because ischemic stroke is more common than hemorrhagic, the investigators expect a smaller proportion of volunteers from the latter group. * Chronic stroke. Individuals with chronic stroke, defined as \>6 months post infarct, will be included. * Able to walk 10 m. Stroke survivors capable of walking 10 m overground will be admitted. Canes, walkers, braces, and other devices will be allowed. This study examines the effect of CUped on gait kinematics and kinetics; therefore, the ability to walk is imperative. * Unilateral motor impairment consistent with hemiparesis. * Learned non-use of the paretic limb. Non-use will be verified by comparing paretic limb work (W) during unilateral and bilateral coupled pedaling. Participants with non-use will be identified as those who produce significantly \<50% of the total W of bilateral coupled pedaling with their paretic limb but are capable of unilateral pedaling with the paretic limb at a workload equivalent to 50% of the total W of bilateral coupled pedaling. (Significance will be determined using a 1-sample t-test or corresponding non-parametric test in the case of non-normality). * No contraindications for exercise. Contraindications to exercise include but may not be limited to recent electrocardiogram changes or recent myocardial infarction, uncontrolled arrhythmia, unstable angina, third degree heart block, acute progressive heart failure, uncontrolled hypertension, and orthopedic conditions (e.g., severe muscle contracture, arthritis, acute limb injury) that may interfere with pedaling. * Age ≥18. All participants must be at least 18 years of age. The investigators are studying adult not childhood stroke. Recovery mechanisms are different between adult and childhood stroke survivors. * Able to commit to 27 visits to the lab (pre-, mid-, post-test, plus 24 training sessions). Exclusion Criteria: * More than 1 stroke. Individuals with more than one clinically apparent stroke, as evidenced by residual impairments and/or medical imaging, will be excluded. Individuals with history of transient ischemic attack (TIA) resulting in no residual impairments or brain damage will NOT be excluded. * Stroke in the cerebellum or basal ganglia. Individuals with stroke affecting primarily the cerebellum or basal ganglia will be excluded. The cerebellum has an important role in motor learning. Given that CUped depends on motor learning, people with cerebellar strokes may not benefit. Basal ganglia strokes can cause tremor, which is not the target of CUped. However, individuals with predominantly internal capsule lesions that also affect the basal ganglia will be included. * Dementia or other cognitive impairment that interferes with learning and/or the ability to consent. * Communication impairments, such as receptive aphasia, that prevent safe participation. Expressive aphasia is not an exclusion criterion. Participants will be included as long as they have a method to communicate willingness to participate, discomfort, and/or the desire to start or stop a study activity. * Orthopedic impairments that interfere with pedaling. * Cardiovascular contraindications to exercise. * Inability to walk 10 m overground. Participants will be excluded in they are not able to walk 10 m overground our cannot do so safely. * Neurological disorder other than stroke. Individuals with history or signs of any neurologic disease or injury other than stroke will be excluded. Such conditions may include head trauma, cerebral palsy, epilepsy, brain tumor, diabetic neuropathy, dementia, multiple sclerosis, Parkinson's disease, or Alzheimer's disease. * Other conditions that interfere with safe participation or data integrity. Participants will be excluded if, at any point in the recruitment or enrollment process, the investigators become aware of a condition that increases risk beyond that indicated in our IRB protocols. Exclusion will also occur if the investigators become aware of a condition that introduces an experimental variable that could confound the results of the study. * Failure to meet any inclusion criteria listed above.