JMIR Publications

ABSTRACT

Background:

The growing interest of the scientific community in trail-running has highlighted the acute effects of the practice at the time of these races on isolated aspects of physiological and structural systems, of functions (biological, physiological, cognitive, muscular) and of psychological state of the athletes. However, no integrative study to date has been carried out under these conditions with so many participants, variables monitored pre-, per- (6 standardised time measurements) and post-race (up to D+10), over a distance close to 100 miles. This integrative and systemic approach will allow a global understanding of the interactions between the determinants of trail-running performance.

Objective:

The aim of this work is to evaluate the kinetics of the performance parameters during a 156 km trail run and 6000 m D+ in pre, per and post race. The general hypothesis is based on significant alterations of the psychological, physiological, mechanical, biological and cognitive parameters.

Methods:

The Trail Scientifique de Clécy is a prospective experimental study providing a comprehensive exploration of constraints and adaptations of psycho-physiological and sociological variables assessed in real race conditions during a trail-running of 156km in hilly terrain (6000m of elevation gain (D+). The race being devided into 6 identical loops of 26km and 1000mD+, the study protocol allowed repeatability of study measurments in same experimental conditions during the race. Measurements were carried out the day before and the morning of the race, at the end of each lap (every 26 km) after a pit stop and up to 10 days after the race. 55 participants were included, 43 men and 12 women, experienced in ultra trail running events and with no contraindications to the practice of this sport. This experimental group took part in a 156 km / 6000mD+ race (between 20 and 46 hours of running) and measurements were carried out the day before and the morning of the race, at the end of each lap (every 26 km), and immediately and up to 10 days after the race.

Results:

The race took place on 11 November 2021, of the 55 runners entered, 41 finished the race and 14 dropped out for various reasons (gastric problems, hypothermia, fatigue, musculoskeletal injuries). All the measurements of each team were completed in full. The race times (ie. excluding measurements) ranged from 17:49:14 for the first runner to 35:55:21 for the last runner. The average time to complete all the measurements for each lap was 64 minutes, ± 3 minutes. The first results specific to each scientific task are expected in April 2022.

Conclusions:

- Clinical Trial: The launch of the study was authorised on 26 October 2021 under the trial number 21-0166 after a favourable opinion from the Comité de Protection des Personnes Ouest III (21.09.61 / SIRIPH 2G 21.01586.000009).