Berger Aaron T, Erickson Darin J, Johnson Kayla T, Billmyer Emma, Wahlstrom Kyla, Laska Melissa N, Widome Rachel
Division of Epidemiology and Community Health, University of Minnesota School of Public Health, Minneapolis, MN.
Department of Organizational Leadership, Policy and Development, College of Education and Human Development, University of Minnesota, Minneapolis, MN.
J Sch Health. 2025 Jan;95(1):70-77. doi: 10.1111/josh.13506. Epub 2024 Nov 3.
We aimed to characterize relationships between delayed high school start time policy, which is known to lengthen school night sleep duration, and patterns in activity outcomes: physical activity, non-school electronic screen time (non-schoolwork), and sports and extracurricular activity among adolescents.
We used data from the START study, a multi-site evaluation of a natural experiment, assessing the effects of a school start time policy change in high schools in the Minneapolis, Minnesota metropolitan area. The study follows students in 2 schools that shifted to a later start time (8:20 or 8:50 am) after baseline year and 3 schools that maintained a consistent, early start time (7:30 am) over the 3-year study period. Activity was measured by participant self-report on an in-school survey. The analysis used a difference-in-differences estimator, in which the changes in each outcome observed in the comparison schools estimate the changes in each outcome that would have been observed in the late-start adopting schools had they not delayed their start times after baseline.
Over 2 years of follow-up, no changes emerged to suggest that later school start times either interfered with, or promoted, any activity-related outcome that was measured.
Communities interested in promoting sleep by delaying start times may do so knowing that there are unlikely to be adverse effects on adolescent physical activity, electronic screen time, or organized sports and activity participation.
A shift to later school start times does not appear to enhance or detract from the healthfulness of students' activity level.
我们旨在描述已知会延长上学日夜间睡眠时间的高中延迟上课时间政策与活动结果模式之间的关系：青少年的体育活动、非学校电子屏幕时间（非课业）以及体育和课外活动。
我们使用了START研究的数据，这是一项对自然实验的多地点评估，评估了明尼苏达州明尼阿波利斯市大都市区高中上课时间政策变化的影响。该研究跟踪了2所学校的学生，这2所学校在基线年后改为较晚的上课时间（上午8:20或8:50），以及3所学校的学生，这3所学校在3年的研究期间保持一致的较早上课时间（上午7:30）。活动通过参与者在学校调查中的自我报告来衡量。分析使用了差异-in-差异估计器，其中在对照学校中观察到的每个结果的变化估计了如果晚开始上课的学校在基线后不延迟上课时间，在这些学校中会观察到的每个结果的变化。
在2年的随访中，没有出现任何变化表明较晚的上课时间会干扰或促进所测量的任何与活动相关的结果。
有兴趣通过延迟上课时间来促进睡眠的社区可以这样做，因为知道这对青少年的体育活动、电子屏幕时间或有组织的体育和活动参与不太可能产生不利影响。
改为较晚的上课时间似乎不会提高或降低学生活动水平的健康程度。
