Study of Thermoregulatory Processes in Ultra-endurance Runners in a Hot and Humid Environment (ERUPTION-2)

Human beings are characterized by their extraordinary ability to thermoregulate.

During a physical exercise, only 20% of the energy provided by the substrates is converted into muscular mechanical work. The remaining 80% is released as heat. In temperate environments, so-called metabolic heat is dissipated by several physical phenomena (radiation, conduction, convection and evaporation). However, if the dissipation capacity (in a hot and humid environment for example) is lower than the production of metabolic heat, the body temperature increases progressively until exercise stops or heat-related pathologies develop. This pathological entity defined by the acronym EHI for Exertional Heat Illness gather a wide spectrum of clinical forms ranging from oedema or heat rash, to muscle cramps, to syncope; up to more serious forms such as heat exhaustion or heat stroke during exercise.

Heatstroke during exercise is the second most common cause of death in athletes after heart disease.

However, the results of the epidemiological studies and the recommendations are limited to events with effort durations or distances not exceeding those of the marathon. They therefore do not consider ultra-endurance disciplines.

These disciplines, defined by durations of effort of at least 6 hours, have specific characteristics (duration of effort, intensity, steep gradients, exotic destinations, extreme environments) which means that extrapolation of the results and knowledge of the physiology of thermoregulation from "classic" endurance events, such as marathons, to ultra-endurance events is hazardous. There are therefore significant areas of uncertainty in understanding the thermoregulatory function, prevalence of EHI (Exertional Heat Illness) and health implications of ultra-endurance running in a hot environment. This is the context of ERUPTION-2.

Study Overview

• Status: Completed
• Conditions: Intensive Sport
• Intervention / Treatment: Other: Biological testing

• Study Type: Interventional
• Enrollment (Actual): 80
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Réunion
  • Saint-Denis, Réunion, 97400
    • Chu Reunion

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Runners participating in " La diagonale des fous " race of the "Grand Raid" 2021 on Reunion Island

Exclusion Criteria:

• Runners who do not understand French

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intervention; Study of Thermoregulatory Processes in Ultra-endurance Runners in a Hot and Humid Environment	Other: Biological testing; Blood sampling, microcapillary sampling, temperature monitoring, saliva testing, EHI questionnaire

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Core temperature measurement	Measure of core temperature (°C) will be carried out by continuous monitoring using e-Celsius performance Bodycap technology sensors carried by the athletes through the race	during 3 days of the race
Natremia measurement	Measure of natremia (blood sodium concentration) will be made by 5 measurements carried out on the eve of the start and during the race, by microcapillary blood sample using the i-STAT technology and CHEM8+ cartridges.	during 3 days of the race
Hydration saliva measurement	Hydration will be measured 5 times carried out on the eve of the start and during the race using saliva sample to measure the salivary osmolarity with the MX3 testing device.	during 3 days of the race
Hydration by weight measurement	Weight in kg will be measured 5 times carried out on the eve of the start and during the race	during 3 days of the race

Collaborators and Investigators

• Sponsor: Centre Hospitalier Universitaire de la Réunion
• Investigators: Principal Investigator: Nicolas Bouscaren, MD, Centre Hospitalier Universitaire de la Réunion

Study record dates

Study Major Dates

• Study Start (Actual): October 19, 2021
• Primary Completion (Actual): October 24, 2021
• Study Completion (Actual): December 31, 2021

Study Registration Dates

• First Submitted: September 15, 2021
• First Submitted That Met QC Criteria: October 16, 2021
• First Posted (Actual): October 28, 2021

Study Record Updates

• Last Update Posted (Actual): April 1, 2022
• Last Update Submitted That Met QC Criteria: March 31, 2022
• Last Verified: March 1, 2022

More Information

Terms related to this study

• Other Study ID Numbers: 2021/CHU/25

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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