Assessment of physical activity level and the influencing factors among middle school students in the main urban area of Beijing

Objective To evaluate the physical activity (PA) level and the influencing factors of middle school students in main urban area of Beijing, and to provide the data support for physical health of middle school students.Methods A total of1 670 middle school students in 3 schools of Haidian and Dongcheng District in Beijing were selected by cluster sampling method, and PA was evaluated with Chinese Version of Adolescent Physical Activity Questionnaire (PAQ-A).Results The average PA score was 2.68±0.81 for all the students, and 2.95± 0.84 for boys, 2.44± 0.69 for girls.PA level of boys was significantly higher than that of girls (t = 6.41, P<0.01), and moderate to vigorous physical activity (MVPA) of boys was also higher than girls' (P<0.01).The average daily screen time was 100 minutes for boys and girls, and there was no significant difference.Total PA and MVPA were higher in junior school students compared with the senior school students (P<0.01), but the screen time of senior school students was significantly higher than that of junior school students (P<0.01).Grade, gender and father's education level could significantly affect PA.Senior school (OR = 2.244, 95%CI = 1.75-2.88) and girls (OR = 3.42, 95%CI = 2.73-4.28) were risk factors for low PA.What' s more, compared with father with the postgraduate degree, the father at the educational level below the junior school (OR = 2.02, 95%CI = 1.13-3.64), senior school (OR = 1.99, 95%CI = 1.32-2.99), with polytechnic and college degree (OR= 1.56, 95%CI = 1.12-2.16) were also the risk factors for the children's PA deficiency.Conclusion Compared with the junior school students, the senior school students' PA is lower and the screen time is longer.PA of boys is higher than that of girls.PA of the children with father with low education level is also low.