title: Energy expenditure during common sitting and standing tasks: examining the 1.5 MET definition of sedentary behaviour.
abstract: BACKGROUND
  Sedentary behavior is defined as any waking behavior characterized by an energy expenditure of 1.5 METS or less while in a sitting or reclining posture. This study examines this definition by assessing the energy cost (METs) of common sitting, standing and walking tasks.
  
  
  METHODS
  Fifty one adults spent 10 min during each activity in a variety of sitting tasks (watching TV, Playing on the Wii, Playing on the PlayStation Portable (PSP) and typing) and non-sedentary tasks (standing still, walking at 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, and 1.6 mph). Activities were completed on the same day in a random order following an assessment of resting metabolic rate (RMR). A portable gas analyzer was used to measure oxygen uptake, and data were converted to units of energy expenditure (METs).
  
  
  RESULTS
  Average of standardized MET values for screen-based sitting tasks were: 1.33 (SD: 0.24) METS (TV), 1.41 (SD: 0.28) (PSP), and 1.45 (SD: 0.32) (Typing). The more active, yet still seated, games on the Wii yielded an average of 2.06 (SD: 0.5) METS. Standing still yielded an average of 1.59 (SD: 0.37) METs. Walking MET values increased incrementally with speed from 2.17 to 2.99 (SD: 0.5 - 0.69) METs.
  
  
  CONCLUSIONS
  The suggested 1.5 MET threshold for sedentary behaviors seems reasonable however some sitting based activities may be classified as non-sedentary. The effect of this on the definition of sedentary behavior and associations with metabolic health needs further investigation.
authors.affiliation: School of Sport, Exercise & Health Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, UK. M.Mansoubi@lboro.ac.uk.
authors.forename: Maedeh
authors.initials: M
authors.lastname: Mansoubi
authors.affiliation: School of Sport, Exercise & Health Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, UK. N.L.Pearson@lboro.ac.uk.
authors.forename: Natalie
authors.initials: N
authors.lastname: Pearson
authors.affiliation: School of Sport, Exercise & Health Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, UK. S.A.Clemes@lboro.ac.uk.|The NIHR Leicester-Loughborough Diet, Lifestyle and Physical Activity Biomedical Research Unit, Leicester-Loughborough, Leicestershire, UK. S.A.Clemes@lboro.ac.uk.
authors.forename: Stacy A
authors.initials: SA
authors.lastname: Clemes
authors.affiliation: Institute of Sport, Exercise & Active Living, Victoria University, Melbourne, Australia. stuart.biddle@vu.ed.au.
authors.forename: Stuart Jh
authors.initials: SJ
authors.lastname: Biddle
authors.affiliation: Leicester Diabetes Centre, Leicester General Hospital, University of Leicester, Leicester, Leicestershire, UK. dhm6@leicester.ac.uk.
authors.forename: Danielle H
authors.initials: DH
authors.lastname: Bodicoat
authors.affiliation: School of Sport, Exercise & Health Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, UK. K.Tolfrey@lboro.ac.uk.
authors.forename: Keith
authors.initials: K
authors.lastname: Tolfrey
authors.affiliation: The NIHR Leicester-Loughborough Diet, Lifestyle and Physical Activity Biomedical Research Unit, Leicester-Loughborough, Leicestershire, UK. ce95@leicester.ac.uk.|Leicester Diabetes Centre, Leicester General Hospital, University of Leicester, Leicester, Leicestershire, UK. ce95@leicester.ac.uk.
authors.forename: Charlotte L
authors.initials: CL
authors.lastname: Edwardson
authors.affiliation: The NIHR Leicester-Loughborough Diet, Lifestyle and Physical Activity Biomedical Research Unit, Leicester-Loughborough, Leicestershire, UK. ty20@leicester.ac.uk.|Leicester Diabetes Centre, Leicester General Hospital, University of Leicester, Leicester, Leicestershire, UK. ty20@leicester.ac.uk.
authors.forename: Thomas
authors.initials: T
authors.lastname: Yates
mesh_terms: D000328:Adult; D001481:Basal Metabolism; D018592:Cross-Over Studies; D004734:Energy Metabolism; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000628:therapy; D010808:Physical Examination; D010988:Play and Playthings; D011998:Recreation; D012015:Reference Standards; D057185:Sedentary Behavior; D018910:Video Games / Q000706:statistics & numerical data; D055815:Young Adult