Low Body TemperaturesNCT05409937
Influence of Wet Clothing on Thermal Protection
A study testing Water-saturated Improved Hot Weather Combat Uniform, Water-saturated Army Combat Uniform and Water-saturated Army Combat Uniform + Silk Weights in people with Low Body Temperatures, run by United States Army Research Institute of Environmental Medicine at 1 site in United States.
Trial 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. Read more about this study
- Who is it for?
- Ages 18 to 49 yearsHealthy volunteers can take part
- Conditions the study is for
- Low Body Temperatures
- What is being tested?
- Water-saturated Improved Hot Weather Combat Uniform, Water-saturated Army Combat Uniform and Water-saturated Army Combat Uniform + Silk Weights
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- 1 siteUnited States
- Study dates
- 2 Sep 2021to 30 Sep 2023
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 49 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- 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.
Who cannot join
- 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.
Trial locations and contacts
1 site in 1 country.
United States1 site, 1 recruiting
- Recruiting
USARIEM
Natick, Massachusetts, 01760
Afton D Seeley, Ph.D., 508-206-2423, afton.d.seeley.civ@health.mil
About this study
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.
Read the detailed description
Participants, in their first visit, will undergo baseline weighted treadmill walking consisting of ~20 min of treadmill walking with a load of 77lbs followed by ~25 min of treadmill walking with a load of 38.5lbs. They will also have their body composition evaluated (DEXA) and be fit for each uniform ensemble. This first laboratory visit will require ~3 hrs.
On separate days, participants will complete 4 experimental trials. After being submerged up to the neck in warm water for two minutes, three of the trials will ask that the participant move to a 41°F air environment, stand with minimal movement for 60 min, complete 60 min of weighted (38.5lb) treadmill walking at 2 mph, and up to 4% grade, and then complete 60 min of weighted (38.5lb) treadmill walking at 2.5 mph and up to 4% grade. Each of these three experimental trial visits will require ~5 hrs.
A single trial will ask that after being saturated in warm water, participants enter a 41°F air environment, immediately begin weighted treadmill walking (38.5lbs) at 2.0mph and up to 4% grade for a duration of 60 min before standing with minimal movement for 60 min. This trial will require ~4 hrs.
During all experimental trials, the primary outcomes include core temperature, measured continuously using a small pill inserted as a rectal suppository, and skin temperature, measured continuously using 11 small skin attached sensors. Secondary outcomes include metabolic rate, heart rate, thermal perceptions, and changes in body mass.
Non-federally employed civilians may be eligible to be paid $13.50/hour for participation (for a total of up to $310).
- Conditions
- Low Body Temperatures
- Being tested
- Water-saturated Improved Hot Weather Combat Uniform, Water-saturated Army Combat Uniform, Water-saturated Army Combat Uniform + Silk Weights
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Water-saturated Improved Hot Weather Combat UniformOther
Water-saturated Improved Hot Weather Combat Uniform
Water-saturated Army Combat UniformOther
Water-saturated Army Combat Uniform
Water-saturated Army Combat Uniform + Silk WeightsOther
Water-saturated Army Combat Uniform + Silk Weights
| Study group | Role | What they receive |
|---|---|---|
| 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. Receives: 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. Receives: 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. Receives: 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 Receives: Other: Water-saturated Army Combat Uniform |
What is being measured
The primary outcome is the main question the study is designed to answer.
Core Temperature
Core temperature will be measured using a temperature pill that is inserted as a rectal suppository.
Measured: 5 hours
Skin Temperature
Skin temperature will be measured using 11 different skin-attached temperature sensors.
Measured: 5 hours
Secondary outcomes (5)
Heart Rate
Heart Rate will be measured using telemetry [beats per min]
Measured: 5 hours
Oxygen Consumption/Metabolic Heat Production (MHP)
Oxygen consumption and MHP will be assessed using computerized indirect calorimetry [ml/kg/min; Watts per meter squared]
Measured: multiple 5 minute collections up to 1 hour
Thermal Sensation (whole body, feet, and hands)
Thermal sensation will be assessed using the American Society of Heating, Refrigerating and Air-conditioning Engineers Thermal Sensation Scale. This scale has numbers from -4 to +4 with every whole number accompanied by a verbal expression. The verbal expressions are used only to give the subject a relative feeling pertaining to the relative sensation. For example, -4 is associated with very cold whereas +4 is associated with very hot.
Measured: multiple 1 minute collections up to 1 hour
Thermal Comfort
Thermal comfort will be assessed using a standard Thermal Comfort Scale. We will ask volunteers to rate how comfortable they feel with respect to temperature sensation. The scale has numbers ranging from 0 to 4 and with descriptors ranging from comfortable (0) to intolerable (4).
Measured: multiple 1 minute collections up to 1 hour
Perceived Skin Wetness
Perceived Skin Wetness will be assessed using an adapted Skin Wetness Perception Scale. The scale ranges from 0 (extremely dry) to -6 (extremely wet; soaked).
Measured: multiple 1 minute collections up to 1 hour
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Jun 2022
- Study start2 Sep 2021
- Primary completion30 Sep 2023 (estimated)
- Study completion30 Sep 2023 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Low Body TemperaturesStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- United States Army Research Institute of Environmental Medicine
- Sponsor type
- US federal agency
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05409937
- Sponsor's protocol ID
- 21-12H
- Status last verified
- Jan 2023
- First submitted
- 24 May 2022
- Last updated
- 27 Jan 2023
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
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.
PubMed 39270307
Study at a glance
From the registry record, last updated by the sponsor on 27 Jan 2023. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Influence of Wet Clothing on Thermal Protection
- ClinicalTrials.gov ID
- NCT05409937
- Acronym / sponsor ID
- 21-12H
- Conditions
- Low Body Temperatures
- Study type
- Interventional
- Recruitment status
- Unknown status
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- United States Army Research Institute of Environmental MedicineUS federal agency
- Study start
- 2 Sep 2021 (actual)
- Primary completion
- 30 Sep 2023 (estimated)
- Study completion
- 30 Sep 2023 (estimated)
- First posted
- 8 Jun 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Detailed description
Participants, in their first visit, will undergo baseline weighted treadmill walking consisting of ~20 min of treadmill walking with a load of 77lbs followed by ~25 min of treadmill walking with a load of 38.5lbs. They will also have their body composition evaluated (DEXA) and be fit for each uniform ensemble. This first laboratory visit will require ~3 hrs.
On separate days, participants will complete 4 experimental trials. After being submerged up to the neck in warm water for two minutes, three of the trials will ask that the participant move to a 41°F air environment, stand with minimal movement for 60 min, complete 60 min of weighted (38.5lb) treadmill walking at 2 mph, and up to 4% grade, and then complete 60 min of weighted (38.5lb) treadmill walking at 2.5 mph and up to 4% grade. Each of these three experimental trial visits will require ~5 hrs.
A single trial will ask that after being saturated in warm water, participants enter a 41°F air environment, immediately begin weighted treadmill walking (38.5lbs) at 2.0mph and up to 4% grade for a duration of 60 min before standing with minimal movement for 60 min. This trial will require ~4 hrs.
During all experimental trials, the primary outcomes include core temperature, measured continuously using a small pill inserted as a rectal suppository, and skin temperature, measured continuously using 11 small skin attached sensors. Secondary outcomes include metabolic rate, heart rate, thermal perceptions, and changes in body mass.
Non-federally employed civilians may be eligible to be paid $13.50/hour for participation (for a total of up to $310).
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| Improved Hot Weather Combat Uniform | Experimental | Other: Water-saturated Improved Hot Weather Combat UniformWearing 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. |
| Army Combat Uniform | Experimental | Other: Water-saturated Army Combat UniformWearing 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. |
| Army Combat Uniform + Silk Weights | Experimental | Other: Water-saturated Army Combat Uniform + Silk WeightsWearing 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. |
| Army Combat Uniform- XR | Experimental | Other: Water-saturated Army Combat UniformWearing 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 |
Who may qualify
- Ages
- 18 to 49 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (8 listed)
- 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.
Key exclusion criteria (8 listed)
- 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).
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Water-saturated Improved Hot Weather Combat UniformWater-saturated Improved Hot Weather Combat Uniform | Other | Improved Hot Weather Combat Uniform |
| Water-saturated Army Combat UniformWater-saturated Army Combat Uniform | Other | Army Combat Uniform, Army Combat Uniform- XR |
| Water-saturated Army Combat Uniform + Silk WeightsWater-saturated Army Combat Uniform + Silk Weights | Other | Army Combat Uniform + Silk Weights |
Primary outcome
Core Temperature
Time frame: 5 hours
Core temperature will be measured using a temperature pill that is inserted as a rectal suppository.
Skin Temperature
Time frame: 5 hours
Skin temperature will be measured using 11 different skin-attached temperature sensors.
5 secondary outcomes
Heart Rate
Time frame: 5 hours
Oxygen Consumption/Metabolic Heat Production (MHP)
Time frame: multiple 5 minute collections up to 1 hour
Thermal Sensation (whole body, feet, and hands)
Time frame: multiple 1 minute collections up to 1 hour
Thermal Comfort
Time frame: multiple 1 minute collections up to 1 hour
Perceived Skin Wetness
Time frame: multiple 1 minute collections up to 1 hour
Results and safety
Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 27 Jan 2023.
- Derived from this study: PubMed 39270307Seeley 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.
- Individual participant dataSharing planned: No
Related trials for Low Body Temperatures
Active, not recruiting
Evaluation of Use of Plastic Bags to Prevent Neonatal Hypothermia-Part I
Hypothermia, Immature Newborn
Not yet recruiting
TECAR Therapy in Chronic Back Pain
Chronic Low-back Pain (cLBP), Non Specific Chronic Low Back Pain
Recruiting
Heat Waves and the Elderly - Cooling Modalities
Aging, Hyperthermia
Recruiting
Title: ICARUS - Psycho-physiological Profiling of Low and High Heat-resilient Individuals
Skin Cancer, Heat Tolerance
Not yet recruiting
Effect of Sevoflurane on Sweat Threshold in Children of Different Ages
Child, Only, Temperature Regulation; Disorder
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Water-saturated Improved Hot Weather Combat Uniform, Water-saturated Army Combat Uniform and Water-saturated Army Combat Uniform + Silk Weights in people with Low Body Temperatures, run by United States Army Research Institute of Environmental Medicine at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 8 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: status not confirmed, as of the sponsor's last update on 27 Jan 2023. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
Contact Afton D Seeley, Ph.D. (508-206-2423, afton.d.seeley.civ@health.mil), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Core Temperature (time frame: 5 hours). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05409937, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 27 Jan 2023.