title: Leisure-Time Physical Activity Does not Attenuate the Association Between Occupational Sedentary Behavior and Obesity: Results From Alberta's Tomorrow Project.
abstract: BACKGROUND
  Sedentary behavior has been proposed as a risk factor for obesity that is distinct from physical inactivity. This study aimed to examine the association between occupational sedentary behavior and obesity, and to determine if this association is independent of leisure-time physical activity (LTPA).
  
  
  METHODS
  Fully employed participants enrolled between 2001 and 2008 to Alberta's Tomorrow Project, a prospective cohort study in Alberta, Canada, were studied (n = 12,409). Associations between occupational sedentary behavior and waist circumference (WC), waist-to-hip ratio (WHR), and body mass index (BMI) were examined using multiple binary and multinomial logistic regressions.
  
  
  RESULTS
  In men, a positive association was observed between daily occupational sedentary hours and WC, WHR, BMI, and with high risk profiles that incorporated both BMI and WC (P < .01). Controlling for vigorous-intensity LTPA in all models strengthened associations between sedentary behavior and measures of obesity. In contrast, inverse associations were observed for occupational sedentary hours and WHR for women (P < .05).
  
  
  CONCLUSIONS
  In fully employed men, occupational sedentary behavior was positively associated with obesity risk that was not attenuated by physical activity. In women, an increase in obesity risk was not observed with sedentary behavior. Gender differences in the health effects of sedentary behavior require further study.
authors.affiliation: University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada.
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Nicholas
authors.forename: Geraldine
authors.initials: G
authors.lastname: Lo Siou
authors.forename: Brigid M
authors.initials: BM
authors.lastname: Lynch
authors.forename: Paula J
authors.initials: PJ
authors.lastname: Robson
authors.forename: Christine M
authors.initials: CM
authors.lastname: Friedenreich
authors.forename: Ilona
authors.initials: I
authors.lastname: Csizmadi
mesh_terms: D000328:Adult; D000368:Aged; D000416:Alberta; D015992:Body Mass Index; D002170:Canada; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004651:Employment; D005260:Female; D006801:Humans; D007899:Leisure Activities; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D009765:Obesity / Q000209:etiology*; D011446:Prospective Studies; D012307:Risk Factors; D057185:Sedentary Behavior; D055105:Waist Circumference; D049629:Waist-Hip Ratio