Circle Of Friends And Physical Activity ——An Empirical Research Based On The Social Networks Of Children And Adolescents

Objective Insufficient physical activity of children and adolescents has become a constraint to the healthy growth of children and adolescents in China.It has become the consensus of governments and social organizations to promote children and adolescents’ physical activity and physical health through schools.Taking the peers and friendship networks of children and adolescents in the campus environment as clues,this study analyzed the relationship between physical activity and friendship networks of children and adolescents in the class from a more microscopic perspective on the basis of verifying the peer effect,which provided theoretical basis and empirical support to promote adolescents’ physical activity.Methods Relied on the questionnaire survey ‘Adolescent Body Posture and Lifestyle’organized and implemented by the research group of the ‘Children and Adolescent Body Posture Assessment System Development and Comprehensive Intervention System’ of the China Institute of Sport Science,this study constructed a least squares regression model（OLS）to estimate the peer effects of physical activity among 7608 children and adolescents aged 6-19.Instrumental variable was introduced to resolve the bias of peer effects which used two-stage least squares（2SLS）.The study also used an exponential random graph model to verify the association between friendship and physical activity among 44 students in a class.Results The rate of children and adolescents reaching the standard of physical activity was worrying,and whether the physical activity of children and adolescents reached the standard was significantly positively correlated with the proportion of their peers who reached the standard of physical activity.Peer effect of physical activity was more significant among children and adolescents from lower grades than those from higher grades.Children and adolescents who liked sports had a significantly higher rate of reaching the physical activity standard than those who didn’t,and those whose parents had a higher education level had a higher probability to reach the physical activity standard.The formation of friendship networks in the class tended to be two-way reciprocity and had a strong transitivity and pre-transmission structure.Compared with boys,girls were more likely to form friendships.There was no significant relationship between the respondents’ friend selection behavior and BMI value,and physical activity was a significant correlative factor for children and adolescents to form friendships in the classroom field.Conclusion:The physical activity of children and adolescents had significant peer interaction exogenous effects.（2）The probability of forming friendship between girls was higher than that between boys,but the peer effect of physical activity in boys was more significant than that in girls.（3）The role of family economic capital in the peer effect of children and adolescents’ physical activity was not significant.The proportion of family members participating in physical exercise and the higher education level of family members had significant effects on children and adolescents’ physical activity.（4）Behavioral spillover effects had valuable policy amplification effects.Therefore,schools should provide a physical environment for children and adolescents to participate in physical activities safely and reliably as well as design and develop team sports activities which allow children and adolescents to participate in together with their friends and peers.In terms of communities and families,children and adolescents should be guided to stay active lifestyle and establish healthy behavioral norms.