NCT05098925: ERUPTION-2

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

Completed NA Last updated 1 April 2022

What this trial tests

NA trial testing Biological testing in Intensive Sport in 80 participants. Completed in 31 December 2021.

Timeline

19 October 2021

Primary endpoint
24 October 2021

31 December 2021

Quick facts

Lead sponsor	Centre Hospitalier Universitaire de la Réunion
Phase	NA
Status	Completed
Study type	INTERVENTIONAL
Allocation	na
Design	single group
Masking	none
Primary purpose	prevention
Enrollment	80
Start date	19 October 2021
Primary completion	24 October 2021
Estimated completion	31 December 2021
Sites	1 location across Reunion

Drugs / interventions tested

• Biological testing

Conditions studied

• Intensive Sport — all drugs for Intensive Sport →

Sponsor

Centre Hospitalier Universitaire de la Réunion

Who can join

18 and older, any sex, with Intensive Sport. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

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.

Publications & conference data

1 peer-reviewed publication reference this trial (live from Europe PMC):

1. Thermoregulation and Hydration Dynamics in a 160-km Ultra-Endurance Race in a Tropical Environment: A Field Study on 80 Runners.
   Bouscaren N, Berly L, Descombes G, Tounkara B, et al · · 2026 · PMID 41343039 · DOI 10.1007/s40279-025-02356-6