[Associations of sleep duration with mental health and alcohol use among Korean adults: a secondary analysis of the Korea National Health and Nutrition Examination Survey (2018·2020)].

The outbreak of the coronavirus disease 2019 (COVID-19) pandemic has seriously affected the quality of human life. In particular, previous studies show that the pandemic, along with the resulting lockdowns, school closures, and social distancing measures, had a significant impact on adolescents' mental health []. The pandemic may negatively impact adolescents’ mental health through stress transferred from family members, changes in context and policy, and the disruption of daily routines [,]. Adolescents who had above-average mental health prior to the pandemic have reported increases in emotional issues, conduct disorders, hyperactivity, and peer relationship problems, along with a decrease in prosocial behaviors during this period []. Numerous studies affirm that physical exercise provides a wide range of beneficial physiological, psychological, and neurocognitive effects. These benefits include reductions in stress [], anxiety [], and depression [], as well as positive effects on cognitive functions such as enhanced executive and memory abilities []. Exercise can function as a cognitive enhancer by boosting neuroplasticity, neurotrophic signaling, and monoaminergic transmission, leading to improved cognitive performance both in the short and long term []. Many studies have shown that exercise-induced improvements in cognitive function (CF) have been associated with local and systemic expression of growth factors in the hippocampus. van Praag et al. [] found the survival of newborn cells in the adult mouse dentate gyrus (DG), a hippocampal region important for spatial recognition, is enhanced by voluntary wheel running. Similarly, spatial pattern separation and neurogenesis in the DG are strongly correlated in three-month-old mice following 10 weeks of voluntary wheel running [], and the development of new neurons in the DG is coupled with the formation of new blood vessels [].