Relationship Between Sedentary Time and Sleep Duration Among Korean Adolescents.

Longer sedentary time and insufficient sleep are common and potentially serious problems among adolescents and have substantially adverse effects on their physical and mental health. In this school-based study, we conducted an ecological momentary assessment using actigraphy to examine the within-subject association between sedentary time and sleep duration among 80 Korean adolescents aged 12-17. Objectively measured sedentary time and sleep duration were recorded over 5 days; participants also completed a self-reported questionnaire and sleep logs. Using a generalized estimating equation, analysis revealed that daily sedentary time was significantly and negatively associated with sleep duration (β = -.36, = .028). Additionally, the interaction between age and sedentary time significantly affected sleep duration (β = .03, = .012). These findings suggest the need for school-based interventions that aim to reduce sedentary time and thereby improve sleep duration, helping adolescents, especially younger ones, to achieve a healthier lifestyle.