Mechanisms of Walking Recovery After Stroke

Study Overview
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Brief Summary
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Subjects with stroke will have behavioral testing and brain imaging before and after a 4-week control period and a 4-week exercise intervention.

Detailed Description
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Subjects with stroke will have behavioral testing and brain imaging before and after a 4-week control period and a 4-week exercise intervention using high-intensity interval training.

Official Title
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Mechanisms of Walking Recovery After Stroke

Conditions
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Stroke

Intervention / Treatment
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* Behavioral: No intervention
* Behavioral: High-intensity interval training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age 30-90 years unilateral stroke experienced >6 months prior to enrollment in middle cerebral artery (MCA) territory without complete disruption of the putamen on the lesion side walking speed <= 1.0 m/s on the 10 meter walk test able to walk 10m over ground with assistive devices as needed and no physical assistance Exclusion Criteria: MRI incompatibility (e.g. metallic or electronic implants, severe claustrophobia) inability to perform mental imagery (time dependent motor imagery screening test [TDMI]) evidence of significant arrhythmia or myocardial ischemia on treadmill ECG stress test, or significant baseline ECG abnormalities that would make an exercise ECG uninterpretable recent (<3 months) cardiopulmonary hospitalization unable to communicate with investigators or correctly answer consent comprehension questions significant ataxia or neglect (score of 2 on NIH stroke scale item 7 or 11) severe lower extremity (LE) spasticity (Ashworth >2) recent (<3 months) illicit drug or alcohol abuse or significant mental illness major post-stroke depression (PHQ-9 ≥10) in the absence of medical management participating in physical therapy or another interventional research study; recent (<3 months) paretic LE botulinum toxin injection concurrent progressive neurologic disorder or other major medical, orthopedic or peripheral vascular conditions that would limit improvement pregnancy

Ages Eligible for Study
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Minimum Age: 30 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Arm 1<br>4-week control period with no intervention and 4-weeks of high-intensity interval training | Behavioral: No intervention<br>* No intervention<br>Behavioral: High-intensity interval training<br>* High-intensity walking exercise using bursts of concentrated effort alternated with recovery periods<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Walking Speed | 10-meter walk test | Change from 4-weeks to 8-weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Gait Symmetry | Paretic step ratio | baseline, 4 weeks, 8 weeks | 
| Metabolic Cost of Gait | oxygen consumption rate during comfortable speed gait | baseline, 4 weeks, 8 weeks | 
| Aerobic Capacity | oxygen consumption rate during exercise testing | baseline, 4 weeks, 8 weeks | 
| NIH Toolbox - Cognition Domain |  | baseline, 4 weeks, 8 weeks | 
| NIH Toolbox Standing Balance Test |  | baseline, 4 weeks, 8 weeks | 
| Stroke and Aphasia Quality of Life Scale |  | baseline, 4 weeks, 8 weeks | 
| Brain Locomotor Network Activation |  | baseline, 4 weeks, 8 weeks | 
| Brain Locomotor Network Connectivity |  | baseline, 4 weeks, 8 weeks | 
| Walking Capacity | 6-minute walk test | baseline, 4 weeks, 8 weeks | 
| Daily Walking Activity | activity monitor | baseline, 4 weeks, 8 weeks | 
| Walking Speed | 10-meter walk test | baseline, 4 weeks, 8 weeks |