Recruiting

Cooling Protocols

Sponsor:

University of Colorado, Colorado Springs

Code:

NCT07433036

Conditions

Hyperthermia

Eligibility Criteria

Sex: All

Age: 18 - 65

Healthy Volunteers: Accepted

Interventions

Passive cooling

Cooling packs

Ice sheets

Body bag cooling

Cold water immersion

Study Details

Brief summary:

This study will help us as scientists and clinicians understand how effective commonly used cooling protocols in emergency departments are and which of the protocols is the most effective.

It consists of a single, approximately 1 hour preliminary session and five, approximately 3 hour experimental sessions, equaling an approximate 16 hour total time commitment.

The purpose of this research is to test the effectiveness of three cooling protocols.

1. Cooling packs
2. "Ice Sheets", which are bed sheets soaked in ice water, wrapped around the participant, while a fan blows air on them.
3. Body bag filled with ice, commonly used in emergency departments to treat hyperthermia

Additionally, a negative control (passive cooling in air-conditioned room) and a positive control (cold water immersion).

Conditions

Hyperthermia

Study ID

NCT07433036

Start date

Jul 1, 2025

Status verified date

Feb, 2026

Completion date

Dec 31, 2028

Anticipated

Primary completion date

Dec 31, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 65

Healthy Volunteers: Accepted

Inclusion Criteria:

  • Active, healthy individuals

Exclusion Criteria:

  • Pregnant or planning on becoming pregnant
  • Have a pacemaker
  • Currently taking any prescribed or over the counter medications or nutritional supplements known to influence thermoregulatory responses
  • Experience lingering pain from a previous musculoskeletal injury (i.e. knee, hip, or back pain)
  • Use tobacco/nicotine products

Study Design

Enrollment

50 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

active comparator: Passive cooling

Participant lies supine in an air-conditioned room

experimental: Cooling packs

During recovery, cooling packs are applied on either side of the neck, both underarms, and both sides of the groin

experimental: Ice sheets

During recovery, participants lie supine and are wrapped in bed sheets that have been soaked in ice water, then have a fan directed towards them while cooling

experimental: Body bag full of ice

During recovery, participants are zipped into a body bag that is full of ice

experimental: Cold water immersion

During recovery, participants are submerged to the neck in a cold water bath

Interventions

Passive cooling

During recovery, participants lie supine in an air-conditioned room

Cooling packs

During recovery, participants lie supine while ice packs are applied to both sides of the neck, both arm pits, and both sides of the groin

Ice sheets

During recovery, participants are wrapped in bed sheets that have been soaked in ice water, while an electric fan blows air across their body

Body bag cooling

During recovery, participants are placed in a body bag full of ice, and then have ice placed on top of their body, followed by zipping the body bag closed.

Cold water immersion

During recovery, participants are submerged in a bath, up to their neck, in cold water water with ice

Primary outcome measure

  • Rectal temperature cooling rate [ Time Frame: The measurement occurs immediately upon completion of the exercise protocol. Time itself is part of the outcome variable and will vary between participants (~3 to 40 min post exercise protocol). ]

Central Contacts and Locations

Central contacts

Nathan Morris, PhD

719-255-4466nmorris6@uccs.edu

Locations

University of Colorado Colorado Springs

Recruiting

Colorado Springs, Colorado, United States, 80918

Contacts

Nathan Morris, PhD

719-255-4466nmorris6@uccs.edu

More Information

Sponsor

University of Colorado, Colorado Springs

Last update posted

Feb 25, 2026

Last verified

Feb, 2026

Keywords

  • Hyperthermia
  • Exercise

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of Colorado, Colorado Springs on 2026-02-25.