Non-invasive Prediction of Thermal Strain in Healthy Male Adults (HUMONHEAT)

Single-centre Experimental Evaluation of Methods for Reliable Non-invasive Prediction of Thermal Strain in Healthy Male Adults

This is primarily an experimental study investigating methods of temperature measurement / heat strain detection. In the calibration study, there are different skin temperature sensor types, and in the prediction study there are different methods for determining heat strain, including conventional methods (rectal, gastro-intestinal), the development of a prediction model, and an index based on heart rate variability.

Study Overview

• Status: Completed
• Conditions: Heat Stress
• Intervention / Treatment: Other: Heat strain

• Study Type: Interventional
• Enrollment (Actual): 13
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • SG
    • St.Gallen, SG, Switzerland, 9014
      • Empa

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

• Apparently healthy males
• aged 18-45 y
• regularly participate in sport, exercise, or equivalent physical activity on a weekly basis.

Exclusion Criteria:

• Known injuries or illnesses that may affect safe participation. These include injuries or illnesses involving (but not limited to):
• cardiovascular, renal, or gastrointestinal tract
• heat or exercise intolerance
• acute infections,
• immunological diseases (including asthma)
• psychiatric disorders.
• Participants must not be currently or previously on cardiovascular-related medication and must not be taking psychotropic medication (last 60 days).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Screening
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: High heat strain; participants exercised at 75% of their heart rate maximum (HR max) and wore light athletic clothing (t-shirt and shorts)	Other: Heat strain; The experimental procedure comprised 15 min baseline seated rest (23.2 ± 0.3°C, 24.5 ± 1.6% relative humidity), followed by 15 min seated rest and cycling in a climatic chamber (35.4 ± 0.2◦C, 56.5 ± 3.9% relative humidity; to +1.5◦C or maximally 38.5°C rectal temperature, duration 20-60 min), with a final 30 min seated rest outside the chamber.
Experimental: Low heat strain; participants exercised at 50% HR max, wearing protective firefighter clothing (jacket and trousers)	Other: Heat strain; The experimental procedure comprised 15 min baseline seated rest (23.2 ± 0.3°C, 24.5 ± 1.6% relative humidity), followed by 15 min seated rest and cycling in a climatic chamber (35.4 ± 0.2◦C, 56.5 ± 3.9% relative humidity; to +1.5◦C or maximally 38.5°C rectal temperature, duration 20-60 min), with a final 30 min seated rest outside the chamber.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Core body temperature	Rectal core body temperature (unit of measure is degree celsius °C)	90 minutes
Predicted core body temperature	Estimated core body temperature (°C) from selected non-invasive measurements: applying a multiple linear regression model several predictive parameters, including skin temperature at different body sites, heat flux at different body sites, and heart rate will be combined to achieve one reported temperature value (°C)	90 minutes
ECG-based heat strain index	ECG-based index of heat strain derived from heart rate variability	90 minutes

Collaborators and Investigators

• Sponsor: Simon Annaheim
• Investigators: Principal Investigator: Simon Annaheim, Dr., Empa, Swiss Federal Laboratories for Materials Science and Technology

Publications and helpful links

Helpful Links

• Published manuscript

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2017
• Primary Completion (Actual): April 30, 2018
• Study Completion (Actual): April 30, 2018

Study Registration Dates

• First Submitted: November 19, 2020
• First Submitted That Met QC Criteria: November 25, 2020
• First Posted (Actual): December 3, 2020

Study Record Updates

• Last Update Posted (Actual): December 3, 2020
• Last Update Submitted That Met QC Criteria: November 25, 2020
• Last Verified: November 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Wounds and Injuries; Heat Stress Disorders
• Other Study ID Numbers: 5213.00095

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Data is available upon request from qualified researchers.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No