Study of Thermoregulatory Processes in Ultra-endurance Runners in a Hot and Humid Environment

Not Applicable

Completed

• Conditions: Intensive Sport
• Interventions: Other: Biological testing

• Registration Number: NCT05098925
• Lead Sponsor: Centre Hospitalier Universitaire de la Réunion

Brief Summary

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.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2021-09-15
• Study First Submitted QC: 2021-10-16
• Study Start: 2021-10-19
• Primary Completion: 2021-10-24
• Study First Posted: 2021-10-28
• Study Completion: 2021-12-31
• Status Verified: 2022-03
• Last Update Submitted: 2022-03-31
• Last Update Posted: 2022-04-01

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 80

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 & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Intervention	Biological testing	Study of Thermoregulatory Processes in Ultra-endurance Runners in a Hot and Humid Environment

Primary Outcome Measures

Name	Time	Method
Core temperature measurement	during 3 days of the race	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
Hydration by weight measurement	during 3 days of the race	Weight in kg will be measured 5 times carried out on the eve of the start and during the race
Natremia measurement	during 3 days of the race	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.
Hydration saliva measurement	during 3 days of the race	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.

Trial Locations

Locations (1)

CHU Réunion; 🇷🇪 Saint-Denis, Réunion