title: Descriptive study of sedentary behaviours in 35,444 French working adults: cross-sectional findings from the ACTI-Cités study.
abstract: BACKGROUND
  Given the unfavourable health outcomes associated with sedentary behaviours, there is a need to better understand the context in which these behaviours take place to better address this public health concern. We explored self-reported sedentary behaviours by type of day (work/non-work), occupation, and perceptions towards physical activity, in a large sample of adults.
  
  
  METHODS
  We assessed sedentary behaviours cross-sectionally in 35,444 working adults (mean ± SD age: 44.5 ± 13.0 y) from the French NutriNet-Santé web-based cohort. Participants self-reported sedentary behaviours, assessed as domain-specific sitting time (work, transport, leisure) and time spent in sedentary entertainment (TV/DVD, computer and other screen-based activities, non-screen-based activities) on workdays and non-workdays, along with occupation type (ranging from mainly sitting to heavy manual work) and perceptions towards physical activity. Associations of each type of sedentary behaviour with occupation type and perceptions towards physical activity were analysed by day type in multiple linear regression analyses.
  
  
  RESULTS
  On workdays, adults spent a mean (SD) of 4.17 (3.07) h/day in work sitting, 1.10 (1.69) h/day in transport sitting, 2.19 (1.62) h/day in leisure-time sitting, 1.53 (1.24) h/day viewing TV/DVDs, 2.19 (2.62) h/day on other screen time, and 0.97 (1.49) on non-screen time. On non-workdays, this was 0.85 (1.53) h/day in transport sitting, 3.19 (2.05) h/day in leisure-time sitting, 2.24 (1.76) h/day viewing TV/DVDs, 1.85 (1.74) h/day on other screen time, and 1.30 (1.35) on non-screen time. Time spent in sedentary behaviours differed by occupation type, with more sedentary behaviour outside of work (both sitting and entertainment time), in those with sedentary occupations, especially on workdays. Negative perceptions towards physical activity were associated with more sedentary behaviour outside of work (both sitting and entertainment time), irrespective of day type.
  
  
  CONCLUSIONS
  A substantial amount of waking hours was spent in different types of sedentary behaviours on workdays and non-workdays. Being sedentary at work was associated with more sedentary behaviour outside of work. Negative perceptions towards physical activity may influence the amount of time spent in sedentary behaviours. These data should help to better identify target groups in public health interventions to reduce sedentary behaviours in working adults.
authors.affiliation: Research Centre for Prevention and Health, The Capital Region of Denmark, Glostrup, Denmark. madina.saidj@regionh.dk.
authors.forename: Madina
authors.initials: M
authors.lastname: Saidj
authors.affiliation: Université Paris 13, Sorbonne Paris Cité - EREN (Equipe de Recherche en Epidémiologie Nutritionnelle), U1153 Inserm, Inra, Cnam, Centre de Recherche en Epidémiologie et Biostatistiques; CRNH IdF, Bobigny, France. m.menai@uren.smbh.univ-paris13.fr.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Menai
authors.affiliation: Université Paris 13, Sorbonne Paris Cité - EREN (Equipe de Recherche en Epidémiologie Nutritionnelle), U1153 Inserm, Inra, Cnam, Centre de Recherche en Epidémiologie et Biostatistiques; CRNH IdF, Bobigny, France. helene.charreire@u-pec.fr.|Paris-Est Créteil University, Department of Geography, Lab-Urba, Urbanism Institute of Paris, Paris, France. helene.charreire@u-pec.fr.
authors.forename: Hélène
authors.initials: H
authors.lastname: Charreire
authors.affiliation: Laboratoire Image, Ville et Environnement, Université de Strasbourg, Strasbourg, France. christiane.weber@live-cnrs.unistra.fr.
authors.forename: Christiane
authors.initials: C
authors.lastname: Weber
authors.affiliation: Laboratoire Image, Ville et Environnement, Université de Strasbourg, Strasbourg, France. christophe.enaux@live-cnrs.unistra.fr.
authors.forename: Christophe
authors.initials: C
authors.lastname: Enaux
authors.affiliation: Research Centre for Prevention and Health, The Capital Region of Denmark, Glostrup, Denmark. mette.aadahl@regionh.dk.|Department of Public Health, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark. mette.aadahl@regionh.dk.
authors.forename: Mette
authors.initials: M
authors.lastname: Aadahl
authors.affiliation: Université Paris 13, Sorbonne Paris Cité - EREN (Equipe de Recherche en Epidémiologie Nutritionnelle), U1153 Inserm, Inra, Cnam, Centre de Recherche en Epidémiologie et Biostatistiques; CRNH IdF, Bobigny, France. e.kesse@uren.smbh.univ-paris13.fr.
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Kesse-Guyot
authors.affiliation: Université Paris 13, Sorbonne Paris Cité - EREN (Equipe de Recherche en Epidémiologie Nutritionnelle), U1153 Inserm, Inra, Cnam, Centre de Recherche en Epidémiologie et Biostatistiques; CRNH IdF, Bobigny, France. s.hercberg@uren.smbh.univ-paris13.fr.|Department of Public Health, Hôpital Avicenne (AP-HP), Bobigny, France. s.hercberg@uren.smbh.univ-paris13.fr.
authors.forename: Serge
authors.initials: S
authors.lastname: Hercberg
authors.affiliation: CARMEN, INSERM U1060/Université de Lyon 1/INRA U1235 Lyon, Lyon, France. chantal.simon@recherche.univ-lyon1.fr.
authors.forename: Chantal
authors.initials: C
authors.lastname: Simon
authors.affiliation: Université Paris 13, Sorbonne Paris Cité - EREN (Equipe de Recherche en Epidémiologie Nutritionnelle), U1153 Inserm, Inra, Cnam, Centre de Recherche en Epidémiologie et Biostatistiques; CRNH IdF, Bobigny, France. jean-michel.oppert@psl.aphp.fr.|Université Pierre et Marie Curie-Paris 6, Department of Nutrition Pitié-Salpêtrière Hospital (AP-HP), Centre for Research on Human Nutrition Ile-de-France (CRNH IdF), Institute of Cardiometabolism and Nutrition (ICAN), Paris, France. jean-michel.oppert@psl.aphp.fr.
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Oppert
mesh_terms: D000293:Adolescent; D000328:Adult; D003201:Computers; D003430:Cross-Sectional Studies; D015444:Exercise; D005260:Female; D005602:France; D015438:Health Behavior; D006801:Humans; D007899:Leisure Activities; D008297:Male; D008875:Middle Aged; D057185:Sedentary Behavior; D057566:Self Report; D014937:Work / Q000706:statistics & numerical data; D055815:Young Adult