HIIT Exercise for Difficulty Walking Due to Stroke

(BReaTHE Trial)

Overseen By Lisa C Krishnamurthy, PhD

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: VA Office of Research and Development

Disqualifiers: Neurodegenerative conditions, Visual impairment, 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: 38

Duration: 12 weeks

55 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to determine if high-intensity interval training (HIIT) can help stroke survivors with leg issues walk faster. Researchers will develop a model to predict who will benefit from HIIT by examining specific body and brain indicators. Veterans who had a stroke at least six months ago and have walking difficulties due to leg problems are eligible to participate. Participants will engage in a 12-week HIIT program to assess improvements in walking speed. As an unphased trial, this study offers Veterans the chance to contribute to innovative research that could enhance rehabilitation strategies for stroke survivors.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What prior data suggests that this HIIT rehabilitation therapy is safe for stroke survivors with lower limb disability?

Research has shown that high-intensity interval training (HIIT) is generally safe for people who have had a stroke. Studies indicate that most participants handle HIIT well, with few serious side effects. While some might experience minor issues, major problems remain uncommon.

HIIT involves short bursts of intense exercise followed by rest periods. For stroke survivors, this exercise can improve walking distance, balance, and overall movement. Participants in various studies demonstrated better mobility and fitness levels after completing HIIT programs.

In summary, HIIT can be a safe exercise option for stroke survivors, offering promising benefits for improving movement and fitness. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about using High Intensity Interval Training (HIIT) for stroke recovery because it offers a dynamic approach to improving mobility. Unlike traditional rehabilitation exercises, which often focus on steady, low-intensity activity, HIIT involves short bursts of vigorous exercise followed by rest. This technique can potentially enhance walking speed more effectively by challenging the cardiovascular system and muscles in a different way. Additionally, HIIT is adaptable and can be customized to each individual's capacity, which may lead to higher engagement and better outcomes in stroke survivors with difficulty walking.

What evidence suggests that HIIT is effective for improving walking speed in stroke survivors?

Research shows that high-intensity interval training (HIIT), which participants in this trial will undergo, can greatly help stroke patients move better. Studies have found that HIIT improves walking ability and heart health. Specifically, some research discovered that HIIT increased walking distance, balance, and brain function in people who have had a stroke. Additionally, one study found that HIIT led to better movement results than moderate exercise. These findings suggest that HIIT could effectively help people with stroke-related leg issues walk faster. ^{1 2 3 6 7}

Who Is on the Research Team?

Lisa C Krishnamurthy, PhD

Principal Investigator

Atlanta VA Medical and Rehab Center, Decatur, GA

Are You a Good Fit for This Trial?

This trial is for veterans who've had a stroke at least 6 months ago, resulting in walking speeds under 0.6 m/s due to lower limb disability. They must not have MRI contraindications like pacemakers or severe claustrophobia, other neurodegenerative conditions affecting the legs, significant visual or auditory impairments, or any health issues preventing physical exercise.

Inclusion Criteria

My walking speed is less than 0.6 m/s due to a stroke.

I had a stroke more than 6 months ago.

Veteran status

Exclusion Criteria

You have a medical condition that would prevent you from participating in a physical exercise program.

I have a condition affecting my brain or nerves that could make it hard to use my legs, other than a stroke.

I have a sight or hearing issue that could affect my participation.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo a 12-week high-intensity interval training (HIIT) intervention to improve walking speed and assess biomarkers.

12 weeks

36 sessions (in-person, 3 times per week)

Follow-up

Participants are monitored for changes in walking speed, balance, leg strength, and endurance after the HIIT intervention.

4 weeks

2 visits (in-person)

What Are the Treatments Tested in This Trial?

Interventions

• High Intensity Interval Training (HIIT)

Trial Overview

The study tests if HIIT can improve walking speed in stroke survivors with lower limb disabilities. It aims to create a model predicting HIIT effectiveness based on early blood lactate levels and brain factors like GABA and regional CBF while considering comorbidities, demographics, and fitness.

How Is the Trial Designed?

Group I: Chronic Stroke with lower limb disability Experimental Treatment 1 Intervention

The investigators will enroll 55 Veterans with chronic subcortical stroke in the 12-week HIIT intervention, with the expectation that 48 participants (85%) will complete the entire program. In our experience, 65% of participants will respond to the HIIT intervention, resulting in an estimated 31 responders and 17 resistors. Each chronic subcortical stroke participant will be asked to participate in the HIIT study protocol. Classification of resistor or responder: A responder to the 12-week HIIT intervention will be defined as a participant who increases their walking speed to greater than 0.6 m/s. A resistor to the intervention will be defined as a participant who does not increase their walking speed to greater than 0.6 m/s.

Who Is Running the Clinical Trial?

VA Office of Research and Development

Lead Sponsor

Trials

1,691

Recruited

3,759,000+

Atlanta VA Medical Center

Collaborator

Trials

28

Recruited

69,700+

Published Research Related to This Trial

High-intensity interval training (HIIT) was found to be safe and feasible for patients with lacunar stroke, with no adverse events reported during the home-based intervention involving 71 participants.

While HIIT did not significantly improve cardiorespiratory fitness compared to usual care, it did increase the time spent on vigorous-intensity activity, suggesting potential benefits in physical activity levels for stroke patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of Home-Based High-Intensity Interval Training in Patients With Lacunar Stroke: A Randomized Controlled Trial. Steen Krawcyk, R., Vinther, A., Petersen, NC., et al.[2023]

A single session of high-intensity interval training (HIT) on a treadmill was found to be feasible for stroke survivors, with participants able to walk at speeds significantly faster than their usual overground walking speed, indicating potential for improved rehabilitation outcomes.

No adverse events occurred during the training, and participants reached heart rates in the vigorous exercise range, suggesting that this HIT approach is safe and could enhance cardiovascular fitness in post-stroke rehabilitation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Feasibility of single session high-intensity interval training utilizing speed and active recovery to push beyond standard practice post-stroke. Aaron, SE., Gregory, CM.[2022]

High-intensity interval training (HIIT) has shown significant improvements in mobility and cardiorespiratory fitness in stroke survivors, based on a systematic review of six studies involving 140 participants.

While HIIT improved peak oxygen consumption compared to baseline, it was not significantly more effective than moderate intensity continuous exercise (MICE); however, it did show superior results in specific mobility tests like the 10-Meter Walk Test and Functional Ambulation Categories.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effectiveness of High-Intensity Interval Training for Fitness and Mobility Post Stroke: A Systematic Review. Wiener, J., McIntyre, A., Janssen, S., et al.[2020]

Eighteen participants with chronic stroke safely completed three different high-intensity interval training (HIIT) protocols, showing no signs of cardiovascular intolerance or significant arrhythmias during the sessions.

HIIT protocols with shorter rest periods (30s and 60s) resulted in significantly higher heart rates and blood pressure compared to longer rest periods (120s), indicating that HIIT can effectively elevate cardiovascular responses in stroke survivors.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Preliminary safety analysis of high-intensity interval training (HIIT) in persons with chronic stroke. Carl, DL., Boyne, P., Rockwell, B., et al.[2020]

In a study involving 55 individuals with chronic stroke, high-intensity interval training (HIIT) led to greater improvements in walking capacity compared to moderate-intensity aerobic training (MAT), primarily due to faster training speeds and improvements in neuromotor gait function.

While HIIT resulted in higher heart rates and lactate levels, these factors did not correlate with improvements in walking distance; instead, prioritizing training speed and step count was found to be crucial for enhancing walking capacity post-stroke.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Training parameters and longitudinal adaptations that most strongly mediate walking capacity gains from high-intensity interval training post-stroke. Boyne, P., Miller, A., Schwab, SM., et al.[2023]

A 6-month exercise program combining high intensity interval training (HIIT) and moderate intensity continuous training (MICT) showed similar improvements in cardiorespiratory fitness (CRF) and mental health markers (anxiety and depression) compared to a standard MICT program in stroke or TIA patients, with both exercise groups outperforming a control group.

Both exercise programs were well-accepted by participants, and the addition of HIIT was found to be safe, indicating that HIIT can be effectively integrated into rehabilitation for stroke patients without compromising safety or efficacy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Addition of high-intensity interval training to a moderate intensity continuous training cardiovascular rehabilitation program after ischemic cerebrovascular disease: A randomized controlled trial. Lapointe, T., Houle, J., Sia, YT., et al.[2023]

High-intensity interval training (HIIT) combined with standard care significantly improved walking distance, balance, and executive function in stroke survivors immediately after the intervention, as shown by improvements in the 6-minute walk test, Berg Balance Scale, and Trail Making Test Part B.

At the 12-month follow-up, only the improvement in executive function (measured by TMT-B) remained significant, indicating that while HIIT has immediate benefits, its long-term effects may be more limited.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of High-Intensity Interval Training After Stroke (The HIIT Stroke Study) on Physical and Cognitive Function: A Multicenter Randomized Controlled Trial. Gjellesvik, TI., Becker, F., Tjønna, AE., et al.[2022]

High-intensity interval training (HIT) may be more effective than conventional aerobic exercise for improving aerobic capacity and functional recovery in stroke patients, based on preliminary studies.

The review emphasizes the need for a structured approach to HIT protocols and highlights the importance of assessing safety, as there has been limited research on the safety of HIT specifically for poststroke individuals.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

High-intensity interval training in stroke rehabilitation. Boyne, P., Dunning, K., Carl, D., et al.[2021]

A study involving 71 patients with lacunar stroke showed that early home-based high-intensity interval training (HIIT) did not lead to long-term improvements in cardiorespiratory fitness over 12 months, despite initial increases in vigorous-intensity activity during the intervention.

Both the HIIT and usual care groups experienced a decline in vigorous-intensity activity back to baseline levels by 12 months, highlighting the need for strategies to maintain physical activity after stroke.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

High-intensity training in patients with lacunar stroke: A one-year follow-up. Krawcyk, RS., Vinther, A., Petersen, NC., et al.[2023]

A pilot study involving 10 stroke participants showed that combined overground and treadmill high-intensity interval training (HIIT) significantly improved gait function, with overground speed changes averaging 61% of those seen on the treadmill after a 4-week treatment phase.

The study highlighted the importance of considering baseline gait speed and including measures of cognition, fatigue, and brain volume in future HIIT research for stroke rehabilitation, as these factors can influence treatment outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Preliminary Outcomes of Combined Treadmill and Overground High-Intensity Interval Training in Ambulatory Chronic Stroke. Boyne, P., Doren, S., Scholl, V., et al.[2022]

Citations

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Secondary results from the HIIT Stroke Study showed a significant increase in walking distance, balance, and executive function immediately after 8 weeks of ...

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JAMA study finds that high-intensity interval training improves stroke patients' mobility more than moderate aerobic exercise · About the study.

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ahajournals.org

ahajournals.org/doi/10.1161/JAHA.123.031532

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These findings show proof of concept that HIIT yields greater improvements in cardiorespiratory fitness than conventional MICT in appropriately screened ...

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Results have been promising, suggesting that HIIT may be superior for improving mobility, with the greatest gains in V̇O2peak achieved after long ...