Behavioural Science Institute, Radboud University, Nijmegen, The Netherlands.
Department of Exercise Sciences, The University of Auckland, Auckland, New Zealand.
Eur J Sport Sci. 2021 Jan;21(1):7-15. doi: 10.1080/17461391.2020.1722255. Epub 2020 Feb 25.
Despite an elevated recovery need, research indicates that athletes often exhibit relatively poor sleep. Timing and consolidation of sleep is driven by the circadian system, which requires periodic light-dark exposure for stable entrainment to the 24-hour day, but is often disturbed due to underexposure to light in the morning (e.g. low-level indoor lighting) and overexposure to light in the evening (e.g. environmental and screen-light). This study examined whether combining fixed sleep schedules with light regulation leads to more consolidated sleep. Morning light exposure was increased using light-emitting goggles, whereas evening light exposure was reduced using amber-lens glasses. Using a within-subject crossover design, twenty-six athletes (14 female, 12 male) were randomly assigned to start the intervention with the light-regulation-week or the no light-regulation-week. Sleep was monitored by means of sleep diaries and actigraphy. Due to low protocol adherence regarding the fixed sleep-wake schedules, two datasets were constructed; one including athletes who kept a strict sleep-wake schedule ( = 8), and one that also included athletes with a more lenient sleep-wake schedule ( = 25). In case of a lenient sleep-wake schedule, light regulation improved self-reported sleep onset latency (Δ SOL = 8 min). This effect was stronger (Δ SOL = 17 min) and complemented by enhanced subjective sleep quality in case of a strict sleep-wake schedule. None of the actigraphy-based estimates differed significantly between conditions. To conclude, light regulation may be considered a potentially effective strategy to improve subjective sleep, but less obtrusive methods should be explored to increase protocol compliance.
尽管运动员的恢复需求较高，但研究表明，他们的睡眠往往相对较差。睡眠的时间和巩固受昼夜节律系统驱动，该系统需要周期性的明暗暴露，以稳定地适应 24 小时的一天，但由于早晨光照不足（例如低水平的室内照明）和晚上光照过度（例如环境和屏幕光），常常会受到干扰。本研究探讨了固定的睡眠时间和光照调节相结合是否能导致更巩固的睡眠。使用发光护目镜增加早晨的光照暴露，而使用琥珀色镜片减少晚上的光照暴露。采用自身交叉设计，26 名运动员（14 名女性，12 名男性）被随机分配到开始干预时使用光照调节周或不使用光照调节周。通过睡眠日记和活动记录仪监测睡眠。由于对固定的睡眠-觉醒时间表的遵守程度较低，因此构建了两个数据集；一个包括严格遵守睡眠-觉醒时间表的运动员（ = 8），另一个也包括睡眠-觉醒时间表较宽松的运动员（ = 25）。如果睡眠时间较宽松，光照调节可改善自我报告的入睡潜伏期（Δ SOL = 8 分钟）。如果睡眠时间严格，这种效果更强（Δ SOL = 17 分钟），并且主观睡眠质量也得到了提高。在任何基于活动记录仪的估计中，条件之间都没有显著差异。总之，光照调节可能被认为是改善主观睡眠的一种潜在有效策略，但应探索更不干扰的方法来提高方案的依从性。
