Brain Blood Flow Responses During Exercise

Study Overview
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Brief Summary
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Brain blood flow will be measured during exercise using magnetic resonance imaging.

Detailed Description
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Over 6 million Americans are living with Alzheimer's disease and related dementias and this number is expected to reach over 13 million by 2060. Thus, there is an urgent need for interventions to prevent the development and progression of Alzheimer's disease and related dementias. Regular exercise is currently the most promising strategy as it is repeatedly shown to have neuroprotective benefits. Evidence suggests that the neuroprotective effects of exercise is the result of improved health of blood vessels. Despite the vast amount of evidence on the benefit of exercise on the peripheral vasculature, there is little information regarding brain vascular responses during exercise. This study will investigate the impact of exercise at varying intensities on brain blood flow during exercise, and will also examine the influence of age and sex.

Official Title
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Influence of Biological Sex and Age on Cerebral Blood Flow and Vessel Function During Exercise: a Pilot Study

Conditions
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Cerebrovascular Circulation, Magnetic Resonance Imaging

Intervention / Treatment
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* Device: MRI


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy men or women between the ages of 20-40 year or 55-69 years Demonstrate an exercise history of engaging in aerobic physical activity at least 3 times per week for a minimum of 30 continuous minutes Have experience using cardiovascular exercise equipment (e.g., treadmill, elliptical, upright or recumbent bicycle, stair-stepper) Exclusion Criteria: Outside of specified age range Do not have experience using cardiovascular exercise equipment Do not meet the physical activity criteria Present with a history or evidence of hepatic, renal, hematological disease, cardiovascular disease including uncontrolled hypertension, peripheral vascular disease, stroke/neurovascular disease, and diabetes have a body mass index ≥30 kg/m2 are ≥ 71 inches (180 cm) in height have any contraindications to MRI currently use or have a history of use of tobacco or illegal substances have current and/or a history of depression or other mood related disorders (those with mild depression and/or anxiety that is controlled with medication and/or therapy will not be excluded) vulnerable populations (e.g., pregnant women, prisoners, individuals lacking capacity to consent) if the desired moderate/vigorous exercise intensity corresponds to > 350 watts on the stepper device

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 69 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 |
| --- | --- |
| Young Adults<br>Young Adults between 20-40 years of age. | Device: MRI<br>* Participants will undergo an MRI scan while performing exercise at two intensities (light and moderate/vigorous) using an MRI-compatible stepper device.<br>|
| Middle-Aged Adults<br>Middle-Aged Adults between 55-69 years of age. | Device: MRI<br>* Participants will undergo an MRI scan while performing exercise at two intensities (light and moderate/vigorous) using an MRI-compatible stepper device.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cerebral Artery Dilation | The change in cross-sectional area of the cerebral arteries during exercise will be measured with MRI. | One study visit, up to 120 minutes | 
| Cerebral Blood Flow | The change in intracranial blood flow during exercise will be measured with MRI. | One study visit, up to 120 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Magnetic Resonance Imaging, Exercise, Brain Blood Flow