Récupération, Performance, Fatigue, Polysomnographie, Architecture du sommeil, Thermorégulation, Environnement de sommeil, Périodisation de l'entraînement

Sleep is essential for the health, well-being, and performance of athletes. However, numerous studies report a high prevalence of inadequate sleep among elite athletes. The high training load imposed to prepare for major competitions is a potential disruptor of sleep in elite athletes that not yet fully understood. In this context, it is essential to develop strategies to mitigate sleep disturbances in athletes. The aim of this PhD thesis was to deepen our understanding of the impact of training load on athletes' sleep and to explore the effectiveness of a high-heat-capacity mattress topper (HMT), a strategy aimed at promoting body heat loss during sleep, on athletes' sleep within typical training contexts. The first study aimed to assess the sleep of young elite rugby union players during a training camp. In this context, in which training load was controlled and not excessive, the distance covered at high-speed promoted sleep duration and the continuity of sleep architecture. Sleep duration and efficiency were sensitive to the morning appointment time, with a negative impact when it was earlier than usual. The second study aimed to examine the impact of a training program consisting of a usual training period, overload, and tapering, on the sleep of well-trained runners. The effectiveness of HMT on sleep was assessed during this training period. An increase in weekly internal training load improved the proportion of slow-wave sleep, sleep onset latency, and the continuity of sleep architecture. A more restless sleep was observed following an increased daily internal training load, particularly during the overload period. The use of HMT did not significantly affect sleep-wake patterns and sleep architecture compared to control bedding. Finally, the third study of this PhD thesis examined the effectiveness of HMT on the sleep of elite badminton players during a summer training period. Sleeping on HMT did not affect sleep-wake patterns and sleep architecture compared to control bedding. However, a most likely increase in sleep efficiency and an almost certainly decrease in wake after sleep onset were observed using HMT compared to control bedding, only in players with more restless sleep. In conclusion, our results highlight the adaptive nature of sleep architecture in response to recovery needs associated with increased training load. We recommend allocating particular attention to sleep when exposed to excessive and unusual training loads, considering the time and organizational constraints associated with this congested period. Further research on the effectiveness of HMT on athletes' sleep with an individualized approach is warranted.