Self‐reported sleep quantity, quality and sleep hygiene in elite athletes
Actigraphy‐based sleep estimates indeed reveal suboptimal sleep in athletes, expressed in relatively high sleep fragmentation, low sleep efficiency and consequently low sleep durations (Lastella et al., 2015; Leeder et al., 2012). However, the extent to which athletes also experience their sleep as suboptimal remains unclear. This may be important as the need for sleep varies between individuals: some may complain about poor sleep quality although objective markers indicate sufficient sleep quality, while others report good sleep quality despite objective markers of poor sleep (Krystal and Edinger, 2008). Hence, assessing subjective sleep quantity and quality is a valuable extension to the current actigraphy‐based sleep estimates. Insight in subjective markers of sleep sheds light on sleep need and recovery status in elite athletes and, importantly, it highlights areas for sleep optimization.
In order to optimize elite athletes’ sleep, it has been suggested to improve their sleep hygiene (Lastella et al., 2015). Sleep hygiene encompasses all conditions and practices that promote continuous and effective sleep, including regularity of bed‐ and rise times, restriction of alcoholic and caffeinated beverages, regular exercise, nutrition, and environmental factors that enhance restful sleep (American Academy of Sleep Medicine, 2001). Evidence suggests that anxiety, noise, the need to use the bathroom and unfavourable competition times disrupt sleep in athletes (Lastella et al., 2014). Unsurprisingly, adherence to sleep hygiene is especially challenging in athletes due to factors such as inter‐meridian travel (Fowler et al., 2015), unfavourable training schedules (Sargent et al., 2014) and late competition times (Reilly and Edwards, 2007). Therefore, it is important to have a complete picture of elite athletes’ sleep hygiene practices, and to what extent specific daytime behaviours and environmental conditions are related to sleep. Apart from a few studies that have investigated the prevalence and impact of selected sleep hygiene factors such as blue‐light exposure and pre‐competitive anxiety (Fietze et al., 2009; Lastella et al., 2014; Romyn et al., 2016), such information is currently lacking.
Working towards future interventions, the present study aimed first, to shed light on subjective sleep quantity and sleep quality in elite athletes; second, to identify their sleep hygiene practices; and third, to investigate associations between sleep hygiene, sleep quantity and sleep quality. Thereby, this study aims to identify areas for sleep optimization in athletes. To provide a robust answer for these aims, a large group of elite athletes was recruited, and their subjective sleep quantity and quality, as well as their current sleep hygiene practices were assessed. All measures were obtained by using (sub)clinical questionnaires providing insight in general sleep and sleep hygiene behaviours, as well as day‐to‐day measurements over a representative 7‐day self‐monitoring period, providing insight in daily‐monitored sleep and sleep hygiene behaviours. Associations between general and daily‐monitored measures were calculated to indicate converging or diverging evidence. It was hypothesized that subjective measures of sleep quantity and quality resemble sleep insufficiencies based on actigraphy (e.g., Leeder et al., 2012). Because sleep hygiene generally concerns ‘conditions and practices that promote continuous and effective sleep’ (p. 347, American Academy of Sleep Medicine, 2001), associations between sleep hygiene, sleep quantity and quality, both at the general and daily‐monitored level, were expected.