Influence of Wet Clothing on Thermal Protection

NCT05409937 | Unknown

• 1 other identifier: 21-12H
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

The aim of this investigation is to provide guidance for assessing the influence of wet clothing, and its drying time, on body temperature responses during cold air exposure. Twelve healthy and fit adults (men and women aged 18-49) will complete this study. Four cold air exposures (41°F, 180 min) will be randomly conducted, each while wearing a different clothing ensemble that has been saturated by water. During each cold air exposure, you will be asked to rest for 60 min and perform weighted (38.5lbs) treadmill walking for up to 120 min.

Conditions

Low Body Temperatures

Outcome Measures

Primary Outcomes (2)

• Core Temperature

  Core temperature will be measured using a temperature pill that is inserted as a rectal suppository.

  5 hours

• Skin Temperature

  Skin temperature will be measured using 11 different skin-attached temperature sensors.

  5 hours

Secondary Outcomes (5)

• Heart Rate

  5 hours

• Oxygen Consumption/Metabolic Heat Production (MHP)

  multiple 5 minute collections up to 1 hour

• Thermal Sensation (whole body, feet, and hands)

  multiple 1 minute collections up to 1 hour

• Thermal Comfort

  multiple 1 minute collections up to 1 hour

• Perceived Skin Wetness

  multiple 1 minute collections up to 1 hour

Study Arms (4)

Improved Hot Weather Combat Uniform

EXPERIMENTAL

Wearing the Improved Hot Weather Combat Uniform; Asked to perform 60 min of standing with minimal movement, 60 min weighted (38.5lb) treadmill walking at 2.0mph, up to 4% grade, 60 min weight (38.5lb) treadmill walking at 2.5mph, up to 4% grade.

Other: Water-saturated Improved Hot Weather Combat Uniform

Army Combat Uniform

EXPERIMENTAL

Wearing the Army Combat Uniform; Asked to perform 60 min of standing with minimal movement, 60 min weighted (38.5lb) treadmill walking at 2.0mph, up to 4% grade, 60 min weight (38.5lb) treadmill walking at 2.5mph, up to 4% grade.

Other: Water-saturated Army Combat Uniform

Army Combat Uniform + Silk Weights

EXPERIMENTAL

Wearing the Army Combat Uniform + a base layer of silk weights; Asked to perform 60 min of standing with minimal movement, 60 min weighted (38.5lb) treadmill walking at 2.0mph, up to 4% grade, 60 min weight (38.5lb) treadmill walking at 2.5mph, up to 4% grade.

Other: Water-saturated Army Combat Uniform + Silk Weights

Army Combat Uniform- XR

EXPERIMENTAL

Wearing the Army Combat Uniform; Asked to perform 60 min weighted (38.5lb) treadmill walking at 2.0mph, up to 4% grade, followed by 60 min of standing with minimal movement

Other: Water-saturated Army Combat Uniform

Interventions

Water-saturated Improved Hot Weather Combat Uniform OTHER

Water-saturated Improved Hot Weather Combat Uniform

Improved Hot Weather Combat Uniform

Water-saturated Army Combat Uniform OTHER

Water-saturated Army Combat Uniform

Army Combat Uniform; Army Combat Uniform- XR

Water-saturated Army Combat Uniform + Silk Weights OTHER

Water-saturated Army Combat Uniform + Silk Weights

Army Combat Uniform + Silk Weights

Eligibility Criteria

• Age: 18 Years - 49 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Military or civilian, male or female, between the ages of 18 (17 if active duty military) and 49 years.
• Able to carry a rucksack weighing 35 kg (77lbs) for at least 20 minutes and able to carry a rucksack weighing 17.5kg (38.5lbs) for up to 120 minutes
• In good health as determined by our OMSO (Office of Medical Support and Oversight) General Medical Clearance.
• Vaccinated against COVID 19.
• Willing to refrain from heavy exercise and alcoholic beverages for 24 hours before each testing session.
• Willing to refrain from smoking or tobacco use for 8 hours before each testing session.
• Willing to refrain from caffeine ingestion for 12 hours before each testing session.
• Body fat percentage \<18% for males, \< 24% for females, once 6 individuals of higher body fat (18% or greater for males, 24% or greater for females) have completed the study.

You may not qualify if:

• History of cold injuries.
• Raynaud's syndrome.
• Cold-induced asthma/bronchospasm.
• Medications or dietary supplements that could alter cardiovascular, thermoregulatory, or vascular control.
• Heart, lung, kidney, muscle, or nerve disorder(s).
• Planned MRI during or within two days after completing the study.
• Known allergy to adhesives.
• Female and pregnant, planning to become pregnant, or breastfeeding.

Sponsors & Collaborators

• United States Army Research Institute of Environmental Medicine: lead

Study Sites (1)

USARIEM

Natick, Massachusetts, 01760, United States

RECRUITING

Related Publications (1)

• Seeley AD, Bodurtha PO, Greenfield AM, Pitsas DM, Shaw MA, Caldwell AR, Alba BK, Castellani JW, O'Brien C. Wet military uniforms pose low risk of hypothermia while static in mild cold air. Appl Physiol Nutr Metab. 2024 Dec 1;49(12):1763-1772. doi: 10.1139/apnm-2024-0180. Epub 2024 Sep 13.

  PMID: 39270307 DERIVED

Central Study Contacts

Afton D Seeley, Ph.D.

CONTACT

508-206-2423; afton.d.seeley.civ@health.mil

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: FED
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 24, 2022
• First Posted: June 8, 2022
• Study Start: September 2, 2021
• Primary Completion: September 30, 2023
• Study Completion: September 30, 2023
• Last Updated: January 27, 2023

Record last verified: 2023-01

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)