MRI for Brain Blood Flow During Exercise

Overseen By Anna J Howery, MS

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of Wisconsin, Madison

Disqualifiers: Cardiovascular disease, Diabetes, Depression, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 1 Jurisdiction This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 1

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to understand how blood flows in the brain during exercise using a special scan called MRI (Magnetic Resonance Imaging). It seeks healthy individuals who regularly engage in aerobic exercise, such as running or using an elliptical, at least three times a week. Participants should not have serious health conditions like heart disease or diabetes and should feel comfortable using exercise machines. Those who are active and enjoy working out might find this a suitable opportunity. As an unphased trial, this study offers a unique chance to contribute to scientific knowledge about brain health and exercise.

Will I have to stop taking my current medications?

The trial protocol does not specify whether you need to stop taking your current medications. However, if you have mild depression or anxiety controlled with medication, you will not be excluded.

What prior data suggests that MRI is safe for measuring brain blood flow during exercise?

Research has shown that MRI, or magnetic resonance imaging, provides a safe and comfortable method for studying the brain. It uses strong magnets and radio waves to capture brain images and is commonly used in hospitals. Unlike X-rays or CT scans, MRI does not involve radiation, enhancing its safety profile. No major side effects are known, though some individuals might feel cramped inside the machine.

In studies using MRI to examine brain blood flow during exercise, researchers found no major safety issues. This confirms MRI as a safe method to observe how exercise affects brain blood flow. Overall, MRI is considered safe, with many individuals undergoing the procedure without problems. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about using MRI to study brain blood flow during exercise because it offers a non-invasive and detailed way to see how exercise affects the brain in real-time. While traditional methods might focus on general physical fitness or heart health, MRI provides a unique look at the brain's vascular system, offering insights that could improve our understanding of brain health and cognitive function. This approach could pave the way for new strategies to enhance brain health through exercise, potentially benefiting young adults and beyond.

What evidence suggests that MRI is effective for measuring brain blood flow during exercise?

Research has shown that MRI effectively measures changes in brain blood flow during exercise. Studies using MRI have tracked these changes, confirming its usefulness in this area. This trial will use MRI to study brain blood flow in young adults during exercise. Exercise has been shown to increase blood flow to the brain, which can help improve memory and reduce the risk of dementia. Additionally, MRI has demonstrated that exercise can alter the brain's white matter and blood vessels, even after just one week. This suggests that using MRI during exercise can provide clear insights into brain health and function. ^{6 7 8 9 10}

Who Is on the Research Team?

Jill N Barnes, PhD

Principal Investigator

University of Wisconsin, Madison

Are You a Good Fit for This Trial?

This trial is for healthy men and women aged 20-40 who exercise regularly, at least three times a week for 30 minutes. They should be familiar with using cardio exercise equipment but not have a high BMI, any major health issues like heart or kidney disease, or contraindications to MRI.

Inclusion Criteria

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)

I am a healthy adult aged between 20 and 40.

Exclusion Criteria

If the desired moderate/vigorous exercise intensity corresponds to > 350 watts on the stepper device

I am not pregnant, imprisoned, or unable to consent for myself.

My BMI is 30 or higher.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Exercise Testing

Participants undergo exercise testing to measure cerebral blood flow and vessel function using MRI

1 day

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after exercise testing

2 weeks

What Are the Treatments Tested in This Trial?

Interventions

• MRI

Trial Overview The study measures how blood flows in the brain during exercise using an MRI. Participants will perform aerobic physical activities while their brain's blood flow responses are monitored.

How Is the Trial Designed?

Group I: Young Adults Experimental Treatment 1 Intervention

Young Adults between 20-40 years of age.

Who Is Running the Clinical Trial?

University of Wisconsin, Madison

Lead Sponsor

Trials

1,249

Recruited

3,255,000+

Published Research Related to This Trial

The study successfully measured great vessel flow in 16 healthy volunteers during rest and submaximal exercise, demonstrating a strong correlation in flow measurements (r = 0.9, p < 0.0005).

Aortic flow volume significantly increased during exercise, indicating that MR flow mapping can safely quantify changes in blood flow, which may help in assessing hemodynamic issues in patients with cardiac disease.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Measurement of aortic and pulmonary flow with MRI at rest and during physical exercise. Niezen, RA., Doornbos, J., van der Wall, EE., et al.[2019]

In a study involving 11 young, healthy subjects, exercise significantly increased heart rate and total blood flow through the abdominal aorta, demonstrating the body's adaptive response to physical activity.

During exercise, blood flow to the digestive and renal circulations decreased, while infrarenal blood flow surged, indicating a redistribution of blood flow to support active muscles, along with a notable increase in wall shear stress in both the supraceliac and infrarenal aorta.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

In vivo quantification of blood flow and wall shear stress in the human abdominal aorta during lower limb exercise. Taylor, CA., Cheng, CP., Espinosa, LA., et al.[2019]

Using flow-alternating inversion-recovery MRI at 3.0 T significantly improved the signal-to-noise ratio for measuring cerebral perfusion compared to 1.5 T, indicating better imaging quality.

The 3.0 T MRI revealed over 80% more activated brain areas during motor tasks, including activation in the supplementary motor area that was not detected at 1.5 T, suggesting enhanced sensitivity for detecting brain activity.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Pulsed arterial spin labeling: comparison of multisection baseline and functional MR imaging perfusion signal at 1.5 and 3.0 T: initial results in six subjects. Yongbi, MN., Fera, F., Yang, Y., et al.[2006]

During moderate-intensity rhythmic handgrip exercise, cerebral blood flow (CBF) increases while cerebrospinal fluid (CSF) flow decreases, indicating a dynamic relationship between these two systems in maintaining intracranial pressure.

The study involved 26 young healthy participants and used advanced imaging techniques to show that changes in blood and CSF flow are closely correlated, supporting the Monro-Kellie hypothesis of intracranial volume-pressure homeostasis.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Brain blood and cerebrospinal fluid flow dynamics during rhythmic handgrip exercise in young healthy men and women. Tarumi, T., Yamabe, T., Fukuie, M., et al.[2021]

This study successfully used pseudo-continuous arterial spin labeling (pCASL) MRI to measure cerebral blood flow (CBF) during different intensities of exercise in 12 healthy volunteers, revealing that CBF in the hippocampus decreased significantly during both moderate and vigorous exercise, while the motor cortex showed an initial increase during moderate exercise before decreasing during vigorous exercise and recovery.

The findings highlight the importance of using pCASL-MRI for accurate CBF measurements during physical activity, as traditional methods using carotid blood flow may overestimate cerebral perfusion, especially during exercise.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dynamic MR imaging of cerebral perfusion during bicycling exercise. Mast, IH., Baas, KPA., Jørstad, HT., et al.[2022]

High-resolution phase-contrast magnetic resonance imaging (PC-MRI) is effective for quantifying aortic and pulmonary blood flow during both rest and exercise in healthy individuals, as demonstrated in a study with 20 volunteers.

The study found that medium exercise stages (40% heart rate increase) were sufficient to show significant changes in blood flow parameters, suggesting that PC-MRI could be a valuable tool for assessing hemodynamic conditions in patients with cardiovascular and pulmonary diseases.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

High-resolution phase-contrast MRI of aortic and pulmonary blood flow during rest and physical exercise using a MRI compatible bicycle ergometer. Weber, TF., von Tengg-Kobligk, H., Kopp-Schneider, A., et al.[2011]

The study successfully quantified regional cerebral blood flow (rCBF) and volume (rCBV) in gray and white matter using dynamic magnetic resonance imaging in 12 subjects, providing mean rCBF values of 69.7 mL/min for gray matter and 33.6 mL/min for white matter.

An age-related decline in rCBF and rCBV was observed, indicating that this imaging technique could be useful for understanding changes in brain blood flow and volume associated with aging.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Quantification of regional cerebral blood flow and volume with dynamic susceptibility contrast-enhanced MR imaging. Rempp, KA., Brix, G., Wenz, F., et al.[2016]

The newly developed exercise cardiovascular magnetic resonance (ExCMR) protocol using a cycle ergometer shows excellent reproducibility in measuring cardiac function, making it a promising tool for clinical assessments of heart health.

This protocol effectively differentiates athletes from non-athletes based on their exercise capacity, with athletes showing significantly higher cardiac index during peak exercise compared to healthy volunteers, indicating its potential for physiological studies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Assessing exercise cardiac reserve using real-time cardiovascular magnetic resonance. Le, TT., Bryant, JA., Ting, AE., et al.[2018]

In a study of 20 young adults, higher aerobic fitness (measured by V. O2peak) was linked to greater cerebrovascular reactivity (CVR), indicating better blood flow response to carbon dioxide, which is important for brain health.

Interestingly, the study found that higher aerobic fitness was associated with lower baseline cerebral blood flow (CBF) in certain brain regions, suggesting a complex relationship between fitness and brain blood flow dynamics.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Assessment of the Effects of Aerobic Fitness on Cerebrovascular Function in Young Adults Using Multiple Inversion Time Arterial Spin Labeling MRI. Foster, C., Steventon, JJ., Helme, D., et al.[2022]

Citations

1. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/37801027/

Effect of Physical Exercise on MRI-Assessed Brain ... Results: There was a significant improvement in physical fitness (VO2peak in mL/minute/kg) in the intervention group (N = 53) compared to ...

2. withpower.com withpower.com/trial/phase-cerebrovascular-circulation-3-2023-87ea5

MRI for Brain Blood Flow During Exercise Research shows that MRI can effectively measure changes in brain blood flow during exercise, as demonstrated by studies using MRI to track blood flow dynamics ...

3. utsouthwestern.edu utsouthwestern.edu/newsroom/articles/year-2021/exercise-boosts-blood-flow-to-the-brain.html

Exercise boosts blood flow to the brain, study finds The results add to growing evidence that exercise programs may help older adults slow the onset of memory loss and dementia ...

4. royalsocietypublishing.org royalsocietypublishing.org/doi/10.1098/rsfs.2024.0043

Exercise modulates brain pulsatility: insights from q-aMRI ... Exercise was found to reduce pulsatility in CBF while increasing CSF flow and eliminating CSF regurgitation, highlighting a shift towards more ...

5. nature.com nature.com/articles/s41598-021-01630-7

Changes in white matter microstructure and MRI-derived ... We demonstrate that 1 week of exercise is sufficient to induce microstructural and vascular brain changes on a group level, independent of BDNF.

6. mayoclinic.org mayoclinic.org/tests-procedures/brain-mri/about/pac-20582237

Brain MRI (brain magnetic resonance imaging) In a functional MRI, the areas of the brain where there is more blood flow and activity appear brighter on the computer screen. Why it's done.

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10203797/

Exploring the acute effects of running on cerebral blood flow ... We investigated the impact of a single running bout on cerebral blood flow (CBF) and food cue reactivity using functional magnetic resonance ...

8. sciencedirect.com sciencedirect.com/science/article/pii/S2666245025000108

The effect of aerobic exercise on cerebral perfusion in ... Aerobic exercise may improve cerebral perfusion and may thereby attenuate, or delay, cognitive decline.

9. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6444938/

Resting Cerebral Blood Flow After Exercise Training in Mild ... Exercise training has been associated with greater cerebral blood flow (CBF) in cognitively normal older adults (CN). Alterations in CBF, including ...

10. frontiersin.org frontiersin.org/journals/physiology/articles/10.3389/fphys.2024.1447417/full

Editorial: Measuring resting cerebral perfusion using ... MRI-based techniques to measure perfusion metrics together with their associated post-processing methods.