Physical Activity, Sedentary Behavior and Social Support Environment

Background/Purpose:  Physical inactivity and sedentary behavior have gradually become common way of life which poses a health risk for Chinese adolescents. Physical activity (PA), sedentary behavior (SB), and social support environment (SSE) are closely related. It is necessary to explore the inner link between them. Therefore, the purpose of this study was to reexamine the relation among PA, SB and SSE based on the view of physical epidemiological.

Method: A total of 11641^stand 2^ed undergraduate from ECNU (474 boys and 690 girls, Mean =19.67±1.094 age) who voluntarily completed two measures during regular PE lessons. Items of the questionnaires including Social Support for Exercise Behaviors Survey (SSEB, Sallis, J.F, 1987) and Physical Activity and Sedentary Behavior for Adolescent (PASB) modified from three respective validated questionnaires designed by Yingmei Liu (2006), Hardy (2007), and Topolski (2006). The modified questionnaire was judged, revised and finalized by five middle school physical education teachers and three professors in the field of PA. The frequency, time, intensity of PA and SB were measured by PASB. Family and friends’ encouragement, support and criticism on PA were assessed using SSEB. The participants were categorized into underweight, normal weight, and overweight/obese groups based on Chinese CDC criteria.

Analysis/Results: Chi-square test was used to identify differences among three groups in PA, SB and SSE at the 0.05 significance level. a) During the past 7 days, 63.8% and 80.2% of boys and girls performed PA for two days or less with each day lasting more than 30 minutes, respectively. There were 71.1% and 83.7% of underweight boys and girls respectively, performed PA for less than three days a week which is significantly higher than normal weight and overweight/obese groups (χ²=24.411, P<0.05).SB mainly concentrated in screen time, homework, reading for adolescent. b) There were 40.9% of boys and 35.3% of girls chosen “never” or “little” do PA with friends, respectively(χ²=19.92,P<0.001).It is a remarkable fact that 38.3% and 55.5% of overweight/obese boys and girls’ parents “often” and “always” encouraged them to persist in exercise. Nevertheless, the ratio of “criticizeor ridicule my PA” from friends in overweight/obese group were also significantly higher than other groups(boys=16.4%, girls=22.2%, χ²=28.22, P<0.005).

Conclusions: a) Chinese adolescents lack social support environment and have a relatively low level of daily PA, b) Gender and body weight were factors influencing adolescent’s PA and SB. c) Parents and friends’ encouragement and ridiculing reflect a nonlinear relationship with adolescent’ PA levels.