Hot Water Immersion as a Heat Acclimation Strategy in Older Adults

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Clinical Phase

NA

Total Enrollment

12 participants

Study Classification

INTERVENTIONAL

Study Start Date

2022-04-29

Study Completion Date

2023-02-16

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

Aging is associated with impairments in heat loss responses of skin blood flow and sweating leading to reductions in whole-body heat loss. Consequently, older adults store more body heat and experience greater elevations in core temperature during heat exposure at rest and during exercise. This maladaptive response occurs in adults as young as 40 years of age. Recently, heat acclimation associated with repeated bouts of exercise in the heat performed over 7 successive days has been shown to enhance whole-body heat loss in older adults, leading to a reduction in body heat storage. However, performing exercise in the heat may not be well tolerated or feasible for many older adults. Passive heat acclimation, such as the use of warm-water immersion may be an effective, alternative method to enhance heat-loss capacity in older adults. Thus, the following study aims to assess the effectiveness of a 7-day warm-water immersion (\~40°C) protocol in enhancing whole-body heat loss in older adults. Warm-water immersion will consist of a one-hour immersion in warm water with core temperature clamped at 38.5°C. Improvements in whole-body heat loss will be assessed during an incremental exercise protocol performed in dry heat (i.e., 40°C, \~15% relative humidity) prior to and following the 7-day passive heat acclimation protocol. The incremental exercise protocol will consist of three 30 minute exercise bouts performed at increasing fixed rates of metabolic heat production (i.e., 150, 200, and 250 W/m2), each separated by 15-minutes of recovery, with exception final recovery will be 1-hour in duration) performed in a direct calorimeter (a device that provides a precise measurement of the heat dissipated by the human body).

Related Clinical Trials

Explore similar clinical trials based on study characteristics and research focus.

Enhancing Heat Resiliency in Older Adults During Indoor Overheating Via Heat Acclimation by Warm Water Immersion

NCT06670365

Hyperthermia Thermoregulation Aging +1 more

RECRUITING NA

Mitigating Heat-induced Physiological Strain and Discomfort in Older Adults Via Lower Limb Immersion and Neck Cooling

NCT05601713

Hyperthermia Weather; Heat Heat Stress +2 more

COMPLETED NA

Cooling Strategies for Older Adults in the Heat

NCT06349616

Aging

COMPLETED NA

Protective Cooling Measures to Safeguard Elderly People From Dangerous Summer Heat

NCT05274009

Hyperthermia Heat; Weather Aging +3 more

UNKNOWN NA

Passive Heat Therapy and Age-associated Physiological Function

NCT03264508

Aging

COMPLETED NA

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Hyperthermia Heat Exposure Heat Stress Thermoregulation Aging

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

NA

Intervention Model

SINGLE_GROUP

Each participant will complete seven consecutive experimental sessions consisting of a passive heat acclimation involving a one hour immersion in warm water (\~40°C) with core temperature clamped at 38.5°C. Prior to and following the passive heat acclimation protocol, study participants will perform an exercise-heat stress test (Days 0 and 8) to assess whole-body heat loss in a hot-dry environment (40°C, 15% relative humidity). The exercise protocol will consist of three successive 30-minute bouts of exercise performed at increasing rates of metabolic heat production (i.e., 150, 200 and 250 W/m2), each separated by a 15-minute rest break, with the final recovery 1-hour in duration.

Primary Study Purpose

BASIC_SCIENCE

Blinding Strategy

NONE

Data will be blinded prior to analysis.

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Heat Acclimation

Participants will undergo an exercise heat stress test prior to and following seven consecutive days of warm-water immersion (\~40°C) of 1-hour duration with core temperature clamped at 38.5°C. During the exercise-heat stress test participants will perform three, successive 30-minute bouts of semi-recumbent cycling performed at increasing fixed loads of metabolic heat production of 150, 200 and 250 W/m2 (i.e., exercise bout 1, exercise bout 2 and exercise bout 3, respectively), each separated by 15-minute of rest break with the final recovery extended to 1-hour.

Group Type EXPERIMENTAL

Heat acclimation

Intervention Type OTHER

Participants will complete a 7-day passive heat acclimation protocol consisting of immersion in warm water (\~40°C) for 1 hour over 7 consecutive days.

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Heat acclimation

Participants will complete a 7-day passive heat acclimation protocol consisting of immersion in warm water (\~40°C) for 1 hour over 7 consecutive days.

Intervention Type OTHER

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* Elderly (60-80 years), non-smoking adults.
* Not engaged in regular physical activity (\>2 sessions/week for ≥20 minutes per session).
* Willing to provide informed consent.
* Healthy, no diagnosed health conditions.
* Body Mass index (BMI) \<35 kg/m2.