title: Associations among sedentary and active behaviours, body fat and appetite dysregulation: investigating the myth of physical inactivity and obesity.
abstract: BACKGROUND
  There is considerable disagreement about the association between free-living physical activity (PA) and sedentary behaviour and obesity. Moreover studies frequently do not include measures that could mediate between PA and adiposity. The present study used a validated instrument for continuous tracking of sedentary and active behaviours as part of habitual daily living, together with measures of energy expenditure, body composition and appetite dysregulation. This cross-sectional study tested the relationship between inactivity and obesity.
  
  
  METHODS
  71 participants (81.7% women) aged 37.4 years (±14) with a body mass index of 29.9 kg/m2(±5.2) were continuously monitored for 6-7 days to track free-living PA (light 1.5-3 metabolic equivalents (METs), moderate 3-6 METs and vigorous >6 METs) and sedentary behaviour (<1.5 METs) with the SenseWear Armband. Additional measures included body composition, waist circumference, cardiovascular fitness, total and resting energy expenditure, and various health markers. Appetite control was assessed by validated eating behaviour questionnaires.
  
  
  RESULTS
  Sedentary behaviour (11.06±1.72 h/day) was positively correlated with fat mass (r=0.50, p<0.001) and waist circumference (r=-0.65, p<0.001). Moderate-to-vigorous PA was negatively associated with fat mass (r=-0.72, p<0.001) and remained significantly correlated with adiposity after controlling for sedentary behaviour. Activity energy expenditure was positively associated with the level of PA and negatively associated with fat mass. Disinhibition and binge eating behaviours were positively associated with fat mass (r=0.58 and 0.47, respectively, p<0.001).
  
  
  CONCLUSIONS
  This study demonstrated clear associations among objective measures of PA (and sedentary behaviour), energy expenditure, adiposity and appetite control. The data indicate strong links between physical inactivity and obesity. This relationship is likely to be bidirectional.
authors.affiliation: Faculty of Medicine and Health, Appetite Control and Energy Balance Research, School of Psychology, University of Leeds, Leeds, UK.
authors.forename: Anna
authors.initials: A
authors.lastname: Myers
authors.affiliation: Faculty of Medicine and Health, Appetite Control and Energy Balance Research, School of Psychology, University of Leeds, Leeds, UK.
authors.forename: Catherine
authors.initials: C
authors.lastname: Gibbons
authors.affiliation: Faculty of Medicine and Health, Appetite Control and Energy Balance Research, School of Psychology, University of Leeds, Leeds, UK.
authors.forename: Graham
authors.initials: G
authors.lastname: Finlayson
authors.affiliation: Faculty of Medicine and Health, Appetite Control and Energy Balance Research, School of Psychology, University of Leeds, Leeds, UK.
authors.forename: John
authors.initials: J
authors.lastname: Blundell
mesh_terms: D050154:Adiposity; D000328:Adult; D001069:Appetite Regulation; D001481:Basal Metabolism; D001823:Body Composition; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D004734:Energy Metabolism; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology; D010809:Physical Fitness; D057185:Sedentary Behavior; D055105:Waist Circumference; D055815:Young Adult
keywords: Body composition; Energy expenditure; Physical activity; Sedentary