Heat Therapy for High Blood Pressure

(ExHT Trial)

Overseen By Dalila G Alves

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: Providence College

Must not be taking: Antihypertensives

Disqualifiers: Hypertension, Heat injury, others

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

Compensation: Varies

Number of Visits: 4

Duration: 4 sessions

20 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores whether a hot leg bath after exercise can lower blood pressure, particularly during sleep. Researchers aim to determine if exercise alone, the hot bath alone (heat therapy), or a combination of both most effectively improves blood pressure and heart health. Participants will engage in four different activities: walking with a lukewarm or hot leg bath, just the hot leg bath, or no activity. The trial suits individuals with blood pressure higher than 120/80 mmHg, who can walk on a treadmill for 30 minutes, and who are not taking blood pressure medication. As an unphased trial, it offers a unique opportunity to explore innovative ways to improve heart health and manage blood pressure naturally.

Will I have to stop taking my current medications?

If you are taking medications for high blood pressure, you cannot participate in this trial, as it excludes those on antihypertensive medications.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that using heat therapy alone can help lower blood pressure. In one study, participants who used heat therapy at home experienced a small decrease in their daytime blood pressure. Specifically, their systolic blood pressure (the top number in a blood pressure reading) dropped by about 5 mmHg, a measure of pressure.

No major safety issues have been reported with heat therapy, indicating it is generally safe to use.

Regarding the combination of exercise and heat therapy, studies have not found a significant change in blood pressure. However, both treatments are considered safe, and many people already exercise and use heat for relaxation.

For those considering joining a trial, current research suggests these treatments are generally well-tolerated. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the Heat Therapy for High Blood Pressure trial because it explores non-traditional approaches that could offer alternatives to standard medications like ACE inhibitors, beta-blockers, or diuretics. This trial investigates the potential of heat therapy and exercise in lowering blood pressure, which could appeal to those seeking lifestyle-based interventions. The unique aspect of combining exercise with a hot leg bath could enhance cardiovascular benefits beyond what exercise alone provides, and heat therapy alone might offer a novel, drug-free option for managing blood pressure. By assessing these innovative methods, researchers aim to uncover new strategies that are both effective and accessible for patients.

What evidence suggests that this trial's treatments could be effective for high blood pressure?

Research has shown that both exercise and heat therapy can help lower blood pressure. In this trial, participants will join different treatment arms to evaluate these effects. One study found that using heat therapy at home reduced daytime systolic blood pressure by about 5 mmHg. Another study demonstrated that soaking in hot water and exercising effectively lowered systolic blood pressure and increased arterial flexibility. In this trial, one arm will combine exercise with hot water immersion, which might offer even greater benefits, potentially lowering blood pressure at night. However, some studies suggest these effects might be limited or similar to just exercising. Overall, these treatments appear to be a promising way to manage high blood pressure. ^{1 2 3 5 6}

Who Is on the Research Team?

Brett R Ely, PhD

Principal Investigator

Providence College

Are You a Good Fit for This Trial?

This trial is for individuals with resting blood pressure higher than 120/80 mmHg, a BMI between 18-39.9, and the ability to walk for 30 minutes at moderate intensity on a treadmill. It's not specified who can't join.

Inclusion Criteria

My blood pressure is higher than 120/80 mmHg.

My BMI is between 18 and 39.9.

I can walk for 30 minutes at a moderate pace on a treadmill.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo four different trials: exercise with lukewarm leg bath, exercise with hot leg bath, hot leg bath alone, and a control day with no intervention

4 sessions

4 visits (in-person)

Follow-up

Participants are monitored for changes in heart rhythm, blood vessel health, and blood pressure after each treatment

24 hours post-treatment

What Are the Treatments Tested in This Trial?

Interventions

• Exercise
• Heat Therapy

Trial Overview The study tests if post-exercise hot water immersion affects overnight blood pressure in people with high blood pressure. Participants will try walking followed by hot or lukewarm leg baths, just a hot bath without exercise, and no treatment to compare effects on heart health.

How Is the Trial Designed?

Group I: Heat Therapy Experimental Treatment 1 Intervention

This treatment will only include the hot leg bath (no exercise).

Group II: Exercise + Heat Therapy Experimental Treatment 2 Interventions

This treatment will include exercise (treadmill walking) and hot leg bath.

Group III: Exercise Active Control 2 Interventions

This treatment will include exercise (treadmill walking) followed by a sham leg bath.

Group IV: Control Active Control 1 Intervention

Participants will refrain from exercise or heat exposure for at least 24 hours, and perform all study analyses for a control comparison.

Who Is Running the Clinical Trial?

Providence College

Lead Sponsor

Trials

1

Recruited

20+

Citations

1. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/40407037/

No effect of either heat therapy or aerobic exercise training on ... Exercise training and heat therapy have similar and limited impacts on blood pressure, arterial stiffness, and biomarkers of kidney function among adults with ...

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC12225054/

No effect of either heat therapy or aerobic exercise training on ... In-clinic blood pressure was similarly unchanged following both aerobic exercise and heat therapy. These pressure responses, along with arterial stiffness and ...

3. clinicaltrials.gov clinicaltrials.gov/study/NCT06348225

Post-exercise Hot Water Immersion to Improve Overnight ... The researchers hypothesize that the combination of exercise and hot water immersion will result in reduced systolic and diastolic blood pressure through 12 ...

4. journals.physiology.org journals.physiology.org/doi/10.1152/japplphysiol.00977.2024

Home-based heat therapy lowers blood pressure and ... This study determined that 8 wk of home-based lower body heat therapy reduced ambulatory daytime systolic blood pressure and increased flow-mediated dilation.

5. faseb.onlinelibrary.wiley.com faseb.onlinelibrary.wiley.com/doi/10.1096/fasebj.2022.36.S1.R6001

Efficacy of Hot Water Immersion versus Aerobic Exercise ... Both hot water immersion and exercise are similarly effective in lowering systolic blood pressure and reducing arterial stiffness in people with untreated ...

6. clinicaltrials.gov clinicaltrials.gov/study/NCT03557502

Heat Therapy Versus Exercise Training in Hypertension This is a clinical trial to determine whether 30 sessions of heat therapy in the form of hot water immersion is better than 30 sessions of traditional aerobic ...