Blood Flow Response and Acute INterval Exercise

Study Overview
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Brief Summary
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The objective of this project is to study the cerebrovascular response to a single bout of high intensity interval exercise (HIIT) in 25 individuals with chronic stroke compared to 25 age- and sex- matched healthy controls (CON). We will enroll 25 young healthy adults (CONyoung) as a reference group. Our hypothesis is that the cerebrovascular response in individuals with chronic stroke will be significantly lower: 1) during a single bout of HIIT, and 2) during the recovery immediately following and 30 minutes after HIIT, compared to CON. This study has 2 visits at the University of Kansas Medical Center Research in Exercise and Cardiovascular Health Laboratory. For the first visit, we will perform questionnaires about heart health, physical activity and overall health. Participants will then complete a submaximal exercise test on a seated stepper. Participants will also have a familiarization session to practice HIIT. The second visit will include cerebrovascular measures before, during, immediately after, and 30 minutes after performing HIIT.

Official Title
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Cerebrovascular Response During Interval Exercise in Chronic Stroke

Conditions
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Stroke, High Intensity Interval Exercise

Intervention / Treatment
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* Behavioral: Single, acute bout of high intensity interval exercise


Participation Criteria
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Eligibility Criteria
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Chronic Stroke Inclusion Criteria: Age 40-80 years old Treated for stroke 6 months to 5 years ago Performs <150 minutes of moderate intensity exercise per week Able to answer consenting questions and follow a 2-step command Chronic Stroke Exclusion Criteria: Stroke etiology due to COVID-19 pathology. Symptoms of COVID-19 and/or Positive COVID-19 test within the past 3 months Unable to stand from a sitting position without physical assistance Recent joint replacement/surgery/poor motor control that limits ability to perform exercise on a recumbent stepper Insulin injection dependent diabetes Dependent on supplementary oxygen History of other neurological disease (Multiple Sclerosis, Alzheimer's disease, Parkinson's disease) Unable to find TCD signal on the stroke-affected or non-affected MCA. CON Inclusion Criteria: Matched age ± 5 years to participant with chronic stroke Matched sex to participant with chronic stroke Performs <150 minutes of moderate intensity exercise per week Able to answer consenting questions and follow a 2-step command CON Exclusion Criteria: Symptoms of COVID-19 and/or Positive COVID-19 test within the past 3 months Unable to stand from a sitting position without physical assistance Recent joint replacement/surgery/poor motor control that limits ability to perform exercise on a recumbent stepper Insulin injection dependent diabetes Dependent on supplementary oxygen History of other neurological disease (Multiple Sclerosis, Alzheimer's disease, Parkinson's disease) Unable to find TCD signal on the right or left MCA. CONyoung Inclusion Criteria: Age 18-30 years old Low cardiac risk (defined by the American College of Sports Medicine) Able to find TCD signal on the right or left MCA

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Chronic Stroke<br>Individuals 40-80 years old who have had a stroke 6 months to 5 years ago. | Behavioral: Single, acute bout of high intensity interval exercise<br>* Individuals will perform a single bout of high intensity interval exercise on a seated recumbent stepper. Participants will perform the pattern of high intensity interval exercise by switching between 1-minute high intensity stepping followed by 1-minute light, active recovery stepping for a total of 10 minutes.<br>|
| CON<br>Control group (CON) comprised of age- and sex-matched healthy adults. | Behavioral: Single, acute bout of high intensity interval exercise<br>* Individuals will perform a single bout of high intensity interval exercise on a seated recumbent stepper. Participants will perform the pattern of high intensity interval exercise by switching between 1-minute high intensity stepping followed by 1-minute light, active recovery stepping for a total of 10 minutes.<br>|
| CONyoung<br>Healthy, young adult control group (CONyoung) who are age 18-30 years old. | Behavioral: Single, acute bout of high intensity interval exercise<br>* Individuals will perform a single bout of high intensity interval exercise on a seated recumbent stepper. Participants will perform the pattern of high intensity interval exercise by switching between 1-minute high intensity stepping followed by 1-minute light, active recovery stepping for a total of 10 minutes.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Middle Cerebral Artery Blood Velocity (MCAv) | blood velocity traveling through the middle cerebral artery measured using the transcranial Doppler ultrasound. | Pre-to-post intervention,  40 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Dynamic Cerebrovascular Autoregulation (dCA) | Ability of the cerebrovascular system to maintain MCAv independent of changes in peripheral blood pressure. Measured using transcranial Doppler ultrasound and mean arterial pressure measured with every heart beat. | Pre-to-post intervention,  40 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cerebral Blood Velocity, Cerebral Autoregulation