(1.School of Physical Education and Health，East China Normal University，Shanghai 200241，China；2.Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education，East China Normal University，Shanghai 200241，China；3.School of Physical Education，Henan Normal University，Xinxiang 453007，China)
Abstract: The study selected 320 school-age children in Henan, measured their screen-based sedentary behaviour and physical activity by the adolescent sedentary activity questionnaire and physical activity questionnaire respectively, and evaluated their cognitive flexibility by the more-odd shifting task to investigate the relationships between screen-based sedentary behaviour and cognitive flexibility and the mediating role of physical activity between them in school-age children. The results showed that: (1) The screen-based sedentary behaviour has a significant negative relation with cognitive flexibility; (2) The indirect effect of screen-based sedentary behaviour impacted the cognitive flexibility by physical activity was -0.0017 (95% CI: -0.0049, -0.0001), confirming that physical activity mediated partly the relationship between screen-based sedentary behaviour and cognitive flexibility; (3) There were significant group differences in the accuracy of both conditions. The cognitive flexibility of school-age children with high-level physical activity was significantly better than that of school-age children with low-level physical activity, and excessive screen-based sedentary behaviour have a more obvious negative impact on the cognitive flexibility of school-age children with low-level physical activity.
Key words: sports psychology；screen-based sedentary behaviour；physical activity；executive function；cognitive flexibility；school-age children