INTRODUCTION Early school start times adversely influence adolescents' sleep duration. Late school start times and remote learning are associated with longer sleep durations. We leveraged a highly variable school schedule adopted after the first SARS-CoV-2 wave in Uruguay to study the influence of a hybrid mode of instruction (in-person/remote) with irregular school start times on adolescents' sleep. METHODS Objective sleep on school nights (120 observations) was determined using accelerometry recordings of 15 high-school students (3 males 15-17 years old). We used mixed-effects regressions to explore the influence of the mode of instruction (in-person/remote) and school start time on adolescents' sleep patterns (onset, end, and duration). RESULTS An irregular individual regime of 2-6 school days per week, either in-person or remote, and with irregular start times (range: 07:30-12:00) were observed during the studied period. Remote learning delayed sleep end by 48 ± 9 min and increased sleep duration by 36 ± 12 min. In addition, 1 h delay in school start time delayed sleep end in 36 ± 4 min and increased sleep duration in 34 ± 5 min. CONCLUSIONS A strong linear association of the mode of instruction and the school start time with participants' sleep was observed: Only waking time was associated with both school start time and mode of instruction, and sleep duration increased when students were taught remotely and when school started later. These results add evidence to the effectiveness of delaying school start time to improve adolescents' sleep. However, these efforts may not overcome the influence of a very late circadian orientation, as observed in Uruguayan adolescents.

中文翻译：

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受到极其不规律的学校时间表的挑战，乌拉圭青少年只设定了他们的起床时间。

引言 早期上学时间会对青少年的睡眠时间产生不利影响。晚开学时间和远程学习与更长的睡眠时间有关。我们利用乌拉圭第一次 SARS-CoV-2 浪潮后采用的高度可变的学校时间表来研究具有不规则开学时间的混合教学模式（面对面/远程）对青少年睡眠的影响。方法 使用 15 名高中生（3 名 15-17 岁的男性）的加速度计记录确定学校晚上的客观睡眠（120 次观察）。我们使用混合效应回归来探索教学模式（面对面/远程）和学校开始时间对青少年睡眠模式（开始、结束和持续时间）的影响。结果 每周 2-6 天的不规则个人制度，无论是面对面还是远程，在研究期间观察到不规则的开始时间（范围：07:30-12:00）。远程学习延迟了 48 ± 9 分钟的睡眠结束，并增加了 36 ± 12 分钟的睡眠时间。此外，开学时间延迟 1 小时，睡眠结束时间延迟 36 ± 4 分钟，睡眠时间延长 34 ± 5 分钟。结之后。这些结果为延迟上学时间以改善青少年睡眠的有效性提供了证据。然而，这些努力可能无法克服非常晚的昼夜节律定位的影响，