Post-exercise Hot Water Immersion to Improve Overnight Blood Pressure

NCT06348225 | Recruiting

• 1 other identifier: FY24-10
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to test whether putting a participant's legs in a hot bath after exercise improves blood pressure in people with higher blood pressure. . The main questions it aims to answer are:

• Whether exercise alone, hot water leg bath alone, or both treatments together cause blood pressure to be lower during sleep.
• If there are any changes in heart rhythm or blood vessel health after exercise, hot water leg bath, or the two treatments together that relate to changes in blood pressure. Participants will complete four different trials:
• 30 minutes of walking with a 45-minute lukewarm leg bath after
• 30 minutes of walking with a 45-minute hot leg bath after
• 45 minutes of a hot leg bath with no exercise
• A day with no exercise or leg bath Researchers will look at heart rhythm, blood vessels, and blood pressure after each of these trials to see if there are differences, and if exercise and heat together can improve heart health more than exercise or heat alone.

Conditions

Elevated Blood Pressure

Keywords

exercise, heat therapy

Outcome Measures

Primary Outcomes (3)

• Ambulatory blood pressure

  Welch-Allyn ambulatory blood pressure monitor placed on the arm after treatment

  24 hours post-treatment

• Heart Rate Variability

  3-lead ECG with paced breathing measured post-treatment

  30-60 min post-treatment

• Flow-mediated dilation

  Measure of endothelial function in the brachial artery (arm), change in blood vessel diameter following a 5-minute blood flow occlusion and release

  30-60 min post-treatment

Study Arms (4)

Exercise + Heat Therapy

EXPERIMENTAL

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

Behavioral: Exercise; Other: Heat Therapy

Heat Therapy

EXPERIMENTAL

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

Other: Heat Therapy

Exercise

ACTIVE COMPARATOR

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

Behavioral: Exercise; Other: Sham leg bath

Control

NO INTERVENTION

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

Interventions

Exercise BEHAVIORAL

Participants will walk on a treadmill for 30 minutes at 55-60% of heart rate reserve. The treadmill will be set at 2mph and 2% grade, then be adjusted in the first 5 minutes to achieve target heart rate.

Also known as: Treadmill walking

Exercise; Exercise + Heat Therapy

Heat Therapy OTHER

Participants will place their legs in a deep leg bath (mid-calf) set to 42C for 45 minutes.

Also known as: hot leg bath

Exercise + Heat Therapy; Heat Therapy

Sham leg bath OTHER

Participants will place their legs in a deep leg bath (mid-calf) set to 36C for 45 minutes.

Also known as: lukewarm leg bath

Exercise

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• resting blood pressure \>120/80 mmHg; measured at screening visit
• BMI between 18-39.9
• capable of walking 30 min at a moderate intensity on a treadmill

You may not qualify if:

• diagnosed hypertension
• taking antihypertensive medications
• history of heat injury or heat illness

Sponsors & Collaborators

• Providence College: lead

Study Sites (1)

Providence College

Providence, Rhode Island, 02918, United States

RECRUITING

MeSH Terms

Conditions

Hypertension; Motor Activity; Hyperthermia

Interventions

Exercise; Diathermy

Condition Hierarchy (Ancestors)

Vascular Diseases; Cardiovascular Diseases; Behavior; Body Temperature Changes; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Heat Stress Disorders; Wounds and Injuries

Intervention Hierarchy (Ancestors)

Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena; Hyperthermia, Induced; Therapeutics

Study Officials

• Brett R Ely, PhD

  Providence College

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Kris A Monahan, PhD

CONTACT

401.865.2554; kmonaha6@providence.edu

Dalila G Alves

CONTACT

401.865.2935; dalves@providence.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: It is not possible to mask the participant to treatments (exercise/no exercise, water temperature, etc) or the PI who is monitoring them during treatment. However, all data (hourly blood pressure, heart rate variability, and flow-mediated dilation) will be analyzed by an individual blinded to the trial/intervention.
• Purpose: PREVENTION
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor of Health Sciences

Model Details: A repeated-measures design will be used with all participants completing the three acute interventions (exercise, heat, or exercise + heat) as well as a control day.

Study Record Dates

• First Submitted: March 28, 2024
• First Posted: April 4, 2024
• Study Start: July 1, 2024
• Primary Completion: December 31, 2025
• Study Completion: December 31, 2025
• Last Updated: August 11, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)