title: Gender- and puberty-dependent association between physical activity and depressive symptoms: national survey among Chinese adolescents.
abstract: BACKGROUND
  The study aims to understand the possible gender difference in the associations between physical activity and depressive symptoms during pubertal transition.
  
  
  METHODS
  Participants were 30,399 children and adolescents of Han ethnicity from urban and rural areas in 8 cities in China. Physical activity (PA) and depressive symptom was assessed by adapted Youth Risk Behavior Survey and Children Depression Inventory (CDI), respectively. Pubertal development was assessed by trained physicians.
  
  
  RESULTS
  In China, over 30% boys and 40% girls reported having no vigorous PA (VPA) or moderate PA (MPA) in the past week. In girls, participating in VPA 1 to 2 days/week showed protective effect for depressive symptoms; whereas in boys, participating in MPA 1 to 2 days/week showed protective effect for depressive symptoms at and after genital stage III (G3).
  
  
  CONCLUSIONS
  Moderate frequency (1 to 2 days/week) in PA undertaken might be encouraged to prevent depressive symptoms among adolescents.
authors.affiliation: Dept of Maternal, Child, and Adolescent Health, School of Public Health, Anhui Medical University, Hefei, Anhui Province, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Sun
authors.forename: Jing
authors.initials: J
authors.lastname: An
authors.forename: Xi
authors.initials: X
authors.lastname: Wang
authors.forename: Ping
authors.initials: P
authors.lastname: Zu
authors.forename: Fang-Biao
authors.initials: FB
authors.lastname: Tao
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002681:China; D003625:Data Collection; D003863:Depression / Q000453:epidemiology* / Q000517:prevention & control; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010555:Personality Inventory; D011627:Puberty; D012737:Sex Factors; D012741:Sexual Maturation