Impact Of Physical Activityon Screen Time, Social Competenceand Quality Of Lifeamong Adolescents: The Multiple Mediating Modeling

PURPOSE: The physical activity (PA) for adolescents’ quality of life (QoL) is an important issue in China. The purpose of this study aimed to identify the effect of PA on screen time, social competence and QoL in Chinese adolescents. METHODS: Participants were 11270 students (boys: 14.14 years ±1.79; girls: 14.22 years ±1.81) randomly selected from 35 secondary schools in Shandong province. The PA, social competence, weekday screen time, and QoL for adolescents were measured. Data were analyzed by utilizing structural equation modeling to test a multiple mediation model. RESULT: The result illustrated that PA was associated with weekday screen time (r = 0.190, P < 0.01), social competence (r = 0.104, P < 0.01) and QoL (r = 0.158, P < 0.01). Weekday screen time was negatively associated with social competence (r = -0.235, P < 0.01) and QoL (r = -0.257, P < 0.01). Social competence was significantly associated with QoL (r = 0.657, P < 0.01). In gender, boys’ PA was significantly associated with weekday screen time (r = 0.192, P < 0.01), social competence (r = 0.111, P < 0.01) and QoL (r = 0.142, P < 0.01), and boys’ PA was also positively associated with physical and mental health (r = -0.135, P < 0.01). In girls, PA was significantly associated with weekday screen time (r = 0.169, P < 0.01), social competence (r = 0.119, P < 0.01), and QoL (r = 0.182, P < 0.01), but negatively associated with physical and mental health (r = -0.068, P < 0.01). The analysis of mediating effects demonstrated that weekday screen time and social competence mediated the effects of PA and QoL. The mediating effects consisted of three paths: “PA → weekday screen time→QoL” “PA → social competence→QoL” “PA → weekday screen time→social competence→QoL”, specifically, PA influenced participants’ screen time and social competence through a multiple mediation effect which enhance QoL. CONCLUSION: This study developed an integrated model of the effect of PA on adolescent’ QoL. It offered robust evidence for this effect by demonstrating the multiple sequential mediating roles of screen time and social competence.