title: Is the Canadian childhood obesity epidemic related to physical inactivity?
abstract: OBJECTIVE
  This study examined the relation among children's physical activity, sedentary behaviours, and body mass index (BMI), while controlling for sex, family structure, and socioeconomic status.
  
  
  METHODS
  Epidemiological study examining the relations among physical activity participation, sedentary behaviour (video game use and television (TV)/video watching), and BMI on a nationally representative sample of Canadian children.
  
  
  METHODS
  A representative sample of Canadian children aged 7-11 (N=7216) from the 1994 National Longitudinal Survey of Children and Youth was used in the analysis.
  
  
  METHODS
  Physical activity and sport participation, sedentary behaviour (video game use and TV/video watching), and BMI measured by parental report.
  
  
  RESULTS
  Both organized and unorganized sport and physical activity are negatively associated with being overweight (10-24% reduced risk) or obese (23-43% reduced risk), while TV watching and video game use are risk factors for being overweight (17-44% increased risk) or obese (10-61% increased risk). Physical activity and sedentary behaviour partially account for the association of high socioeconomic status and two-parent family structure with the likelihood of being overweight or obese.
  
  
  CONCLUSIONS
  This study provides evidence supporting the link between physical inactivity and obesity of Canadian children.
authors.affiliation: College of Kinesiology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada. mark.tremblay@usask.ca
authors.forename: M S
authors.initials: MS
authors.lastname: Tremblay
authors.forename: J D
authors.initials: JD
authors.lastname: Willms
mesh_terms: D000367:Age Factors; D015992:Body Mass Index; D002170:Canada / Q000453:epidemiology; D002648:Child; D004196:Disease Outbreaks; D015444:Exercise; D005191:Family Characteristics; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009765:Obesity / Q000453:epidemiology* / Q000209:etiology; D012307:Risk Factors; D012959:Socioeconomic Factors; D013177:Sports; D013690:Television; D018910:Video Games