The Influence of Sleep and Autonomic Recovery on Performance in World-Class Swimmers at Major Competitions: The Qualifying Trials, World Championships, and Olympic Games

Sleep deprivation is one of the main risk factors for impaired performance in elite athletes, but the changes in sleep and autonomic regulation in response to competitions of varying levels within the same Olympic year remain unknown. In this prospective, longitudinal, observational study, we monitored parameters related to sleep quality and quantity, as well as heart rate variability and resting heart rate, in a cohort of eight Olympic swimmers (n = 8) during the World Championships in Doha, the qualifying trials, and the 2024 Paris Olympic Games, using the Oura Ring Gen3 under real-world conditions throughout the pre-competition, competition, and post-competition phases of each event. The Olympic Games were the only event where sleep efficiency fell below the commonly used reference threshold of 85% during the competition phase accompanied by a reduction in the total sleep score and an increase in resting heart rate. The Olympic setting was accompanied by temporary changes in sleep and autonomic markers, but no sleep parameter or autonomic marker showed a statistically significant association with intra-individual competitive performance, although the limited sample size constrains the power to detect such relationships.