Study On The Status Of Physical Activity And Sedentary Behavior And Affecting Factors Among Part Of High School Students In Shanghai

Objective:To investigate the status of physical activity (PA) and sedentary behavior of partial high school students in Shanghai, study the influences of social support, environment and self-efficacy on PA and sedentary behavior according to the Socio-ecological Framework and Social Cognitive Theory, and to provide scientific basis for further intervention to improve children and adolescents'PA and reduce sedentary behavior.Method:Four districts of Shanghai were selected with stratified cluster sampling, including 2588 junior and senior high school students with 2553 valid questionnaires. The survey includes two questionnaires. One is The Children's Leisure Activity Study Survey Chinese vision for evaluating PA and sedentary behavior, and another is National Student Physical Health Survey for researching daily life behavior. EpiData3.0 was used for double data entering and logical checking. All data used SPSS 13.0 statistical software for processing.Results:1,In the test of reliability and validity shows, Spearman coefficient of correlation of Test-retest reliability of CLASS-C in different intensity is 0.81-0.88, ICC is 0.82-0.89; Spearman coefficient of correlation of sedentary behavior is 0.82-0.85, ICC is 0.82-0.84. In validity test, comparing CLASS-C to SWA, the Spearman coefficient of correlation in weekday and weekend is 0.31-0.47 and 0.32-0.48.2,In this study, the average time of Moderate Physical Activity (MPA) and Vigorous Physical Activity (VPA) of weekday and weekend separately is 51.4min/d,45.3min/d, and 22.1min/d,25.5min/d of boys and girls aged 11-18. There is no significant difference between boys and girls in the time of different intensity of physical activity. In sedentary behavior, the average time of weekday and weekend separately is 8.8h/d and 7.7h/d. The time of sedentary behavior increases with the age grows, and girls have more sedentary time than boys. Compare with physical activity, only sedentary behaviors has positive correlation with BMI.3,In social support, boys on perception of sports equipment ownership rate and partners are significantly higher than girls. The proportions of girls taking part in sports and watching TV with their families are higher than the ones of boys. In different age groups, the proportions of junior groups having sports equipment ownership rate, encouraging from family and taking part in sports with their families and neighbors, watching TV and doing homework with families are higher than senior groups. The one who selects to do activity with families has more time in Moderate to Vigorous Physical Activity (MVPA) and MPV in one week. Encouraging from families and friends has negative correlation with the time of weekday sedentary behavior. And watching with families has positive correlation with the time of sedentary behavior of weekend. 4,In environmental factors, the proportion of boys on perception of sport facilities and partners and intimidating from strangers are significantly higher than girls. The proportions of senior groups having sidewalk in streets around house and fearing of intimidation from strangers are higher than junior groups.5,Boys and junior groups have higher exercise self-efficacy. The ones with different self-efficacy have significant different in perception of sports facilities and partners, and have significant positive correlation with MVPA and VPA of one week, and negative correlation with sedentary behavior.6,The time of sleeping has significant negative correlation with weekday and one week MPA. And with the time of sleeping delay, the time of sedentary is increasing. Cycling and walking to school has significant positive correlation with MVPA and VPA of one week.Conclusions:1,The amendment of CLASS-C has high reliability and validity, and could be used as an easily administrated tool to identify the physical activity and sedentary behavior in Chinese children and adolescents.2,66.5% of children and adolescents have reached the recommended 60 minutes of MVPA per day. But the VPA is less than others. Having classes and doing homework account for 72.8% of the whole time of sedentary behavior. Watching TV and surfing the Internet are the main leisure sedentary behaviors. Sedentary behavior has more effect on BMI.3,Parents have more influence on girl's PA and sedentary behaviors, and neighbors have more effects on boy.4,Family and social support can promote the increasing of physical activities and decreasing of sedentary behavior of adolescents. Parents have important influence on children's lifestyle.5,Self-efficacy has significant effect on adolescent's participation in physical activity and sedentary behavior, as well as the perceptions of social support and surrounding environment.