title: Correlates of Insufficient Physical Activity among Junior High School Students: A Cross-Sectional Study in Xi'an, China.
abstract: BACKGROUND
  Physical activity plays an important role in individual health at all stages of life. However, evidence is lacking regarding the level of moderate to vigorous physical activity (MVPA) and the related factors to insufficient physical activity (IPA).
  
  
  METHODS
  A sample of 1060 students aged 12-15 years from nine public junior high schools in China were invited to participate in this study. Physical activity was assessed by a modified version of the International Physical Activity Questionnaire. Logistic regression was used to assess the factors associated with IPA.
  
  
  RESULTS
  30.1% boys and 43.0% girls in our sample did not engage in sufficient physical activity. Obesity (OR = 2.2, 95% CI: 1.5-2.9) and high socioeconomic status (SES) (OR = 2.4, 95% CI: 1.3-4.8) were positively associated with IPA, whereas male sex (OR = 0.7, 95% CI: 0.5-0.9), underweight status (OR = 0.5, 95% CI: 0.3-0.7), and high family support level for physical activity (OR = 0.7, 95% CI: 0.6-0.9) showed inverse associations. Age was not associated with IPA.
  
  
  CONCLUSIONS
  IPA appears to be a considerable problem in this sample of Chinese youth. Effective interventions to increase physical activity are needed and may include improving family support level for physical activity, especially for girls, the obese and those with high SES.
authors.affiliation: School of Medicine, Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China. wangxiaoqin@mail.xjtu.edu.cn.
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Wang
authors.affiliation: School of Medicine, Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China. huizhaozhao93@163.com.
authors.forename: Zhaozhao
authors.initials: Z
authors.lastname: Hui
authors.affiliation: Department of Medicine, University of Tennessee Medical Center, Knoxville, TN 37996, USA. pdterry@utk.edu.
authors.forename: Paul D
authors.initials: PD
authors.lastname: Terry
authors.affiliation: School of Medicine, Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China. wysun201314195@163.com.
authors.forename: Mei
authors.initials: M
authors.lastname: Ma
authors.affiliation: Faculty of Medicine, The Chinese University of Hong Kong, Shatin 999077, Hong Kong, China. lilycheng@link.cuhk.edu.hk.
authors.forename: Li
authors.initials: L
authors.lastname: Cheng
authors.affiliation: Xi'an Tie Yi High School, Xi'an 710000, Shaanxi Province, China. dengfu01@126.com.
authors.forename: Fu
authors.initials: F
authors.lastname: Deng
authors.affiliation: School of Medicine, Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China. 232guwei@mail.xjtu.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Gu
authors.affiliation: School of Medicine, Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China. zhbin@mail.xjtu.edu.cn.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D044466:Asian People; D002648:Child; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D009043:Motor Activity; D009765:Obesity / Q000453:epidemiology*; D016017:Odds Ratio; D012574:Schools; D012923:Social Class; D013334:Students; D011795:Surveys and Questionnaires
keywords: MVPA; adolescent; family support; obesity; socioeconomic status (SES)