Abstract：
Physical activity is universally acknowledged for its benefits to mental health; however, the specific intensities and timings that best benefit adolescents\' mental health, crucial due to their significant influence on daily schedules, have not been thoroughly investigated. This study addresses the substantive research gap by exploring the varied effects of physical activity intensity (light versus moderate to vigorous) and timing (weekdays versus weekends and holidays) on adolescent mental health. Utilizing a large-scale longitudinal dataset (NT1 = 84,054; NT2 = 44,623) from 158 schools, this research describes the current state of adolescent physical activity and investigates the effects of physical activity on mental health outcomes, including positive (i.e., life satisfaction, positive mental health) and negative indicators (depression, anxiety), over a 6-month period. Participants were adolescents aged 9-19 years (mean age = 12.73 ± 2.43 years, 48.9% female), with the analysis adjusted for potential confounding factors. Results showed that as adolescents grow older, their engagement in moderate-to-vigorous physical activity during both weekdays and weekends/holidays tends to decrease, while light physical activity during weekdays increases. Multilevel regression analysis indicated that moderate-to-vigorous physical activity during weekends/holidays at Time 1 positively correlated with better mental health outcomes at Time 2 (six months later), featuring enhanced positive indicators and reduced negative ones. Moderate-to-vigorous physical activity on weekdays at Time 1 was positively linked to mental health at Time 2. Light physical activity during weekends/holidays at Time 1 positively predicted life satisfaction and positive mental health at Time 2. In contrast, light physical activity on weekdays at Time 1 negatively correlated with life satisfaction at Time 2. The study underscores the importance of promoting moderate-to-vigorous physical activity, particularly on weekends and holidays, to improve mental health outcomes among adolescents.
摘要：
体育活动因其对心理健康的益处而被普遍认可；然而，对青少年心理健康最有益的具体强度和时间，至关重要，因为它们对日常日程安排有重大影响，还没有被彻底调查。这项研究通过探索体育活动强度（轻度，中度至剧烈）和时间（工作日，周末和假期）对青少年心理健康的不同影响来解决实质性研究差距。利用158所学校的大规模纵向数据集（NT1=84,054；NT2=44,623），这项研究描述了青少年身体活动的现状，并调查了身体活动对心理健康结果的影响，包括正(即，生活满意度,积极的心理健康)和消极指标(抑郁，焦虑)，在6个月的时间里。参与者为9-19岁的青少年（平均年龄=12.73±2.43岁，48.9%女性)，分析针对潜在的混杂因素进行了调整。结果表明，随着青少年年龄的增长，他们在工作日和周末/假日期间对中等至剧烈体力活动的参与往往会减少，而工作日的轻度体力活动增加。多水平回归分析表明，在时间1的周末/假日期间的中等至剧烈的体育锻炼与时间2（六个月后）的心理健康结果呈正相关。具有增强的积极指标和减少的消极指标。在时间1的工作日进行适度至剧烈的体育锻炼与时间2的心理健康呈正相关。在时间1的周末/假日期间进行轻度体育锻炼可以积极预测时间2的生活满意度和积极的心理健康。相比之下,时间1工作日的轻度体力活动与时间2的生活满意度呈负相关。这项研究强调了促进中等至剧烈体力活动的重要性，尤其是周末和节假日,改善青少年的心理健康结果。
