Determinants of Sleep and Morning Alertness in Elite Short-Track Speed Skaters During the Preseason

Purpose: Sleep in elite athletes could be compromised by stressors such as high training volumes and mediated by factors related to individual characteristics and training schedule. However, longitudinal real-world data capturing the factors influencing sleep in elite athletes remain scarce. We aimed to determine what predicts sleep quantity, sleep quality, and morning cognitive readiness in elite speed skaters of the Canadian short-track World Cup team. Methods: In the beginning of the preseason period, 16 athletes (7 women) completed the Sleep Health Index, the Insomnia Severity Index questionnaire, and the Caen Chronotype Questionnaire. For 14 consecutive days, athletes filled in detailed logs, performed morning psychomotor vigilance tasks, and wore an actigraphic device. Results: Athletes overestimated their sleep by 9:42 ± 21:34 min:s, sleeping on average 07:56 ± 00:59 hours. Mean psychomotor vigilance-task reaction time was 275 ± 34.5 milliseconds. Sex, chronotype, and nap and training duration explained 34% of the variance in sleep (P < .001). Sleep quality was mainly predicted by a combination of sex, sleep, sleep credit, and chronotype (Akaike information criterion = 49.44). Psychomotor vigilance-task performance was mainly explained by sex, with men being 12.4% faster than women (P < .001). Evening chronotypes were associated with lower sleep duration, whereas men possibly experienced faster recovery. Conclusions: These preliminary results provide insights into factors influencing sleep in speed skaters, such as chronotype, training load, and sex differences, which could be leveraged to optimize training and recovery.