title: Intervening to reduce workplace sitting time: how and when do changes to sitting time occur?
abstract: OBJECTIVE
  To investigate how and when changes in workplace sitting time occurred following a workplace intervention to inform evaluation of intervention success.
  
  
  METHODS
  The 4-week Stand Up Comcare study (June-September 2011) aimed to reduce workplace sitting time via regularly interrupting and replacing sitting time throughout the day. Activity monitor (activPAL3) workplace data from control (n=22) and intervention participants (n=21) were analysed. Differences in the number and usual duration of sitting bouts were used to evaluate how change occurred. To examine when change occurred, intervention effects were compared by hour since starting work and hour of the workday. Change in workplace activity (sitting, standing, stepping) was examined to further inform alignment with intervention messages. Individual variability was examined in how and when the change occurred.
  
  
  RESULTS
  Overall, behavioural changes aligned with intervention aims. All intervention participants reduced total workplace sitting time, though there was wide individual variability observed (range -29 to -262 min per 8 h workday). On average, intervention participants reduced number of sitting bouts (-4.6 bouts (95% CI -10.1 to 1.0), p=0.106) and usual sitting bout duration (-5.6 min (95% CI -9.8 to -1.4, p=0.011)) relative to controls. Sitting time reductions were observed across the workday, though intervention effects varied by hour of the day (p=0.015). The intervention group successfully adopted the Stand Up and Sit Less intervention messages across the day.
  
  
  CONCLUSIONS
  These analyses confirmed that this workplace intervention successfully modified sitting behaviour as intended (ie, fewer and shorter sitting bouts, with changes occurring throughout the day).
authors.affiliation: Cancer Prevention Research Centre, School of Population Health, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Samantha K
authors.initials: SK
authors.lastname: Stephens
authors.affiliation: Cancer Prevention Research Centre, School of Population Health, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Elisabeth A H
authors.initials: EA
authors.lastname: Winkler
authors.affiliation: School of Human Movement Studies, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Stewart G
authors.initials: SG
authors.lastname: Trost
authors.affiliation: Cancer Prevention Research Centre, School of Population Health, The University of Queensland, Brisbane, Queensland, Australia Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia School of Public Health & Preventive Medicine, Monash University, Melbourne, Victoria, Australia School of Sport Science, Exercise & Health, University of Western Australia, Perth, Western Australia, Australia School of Exercise & Sports Science, Deakin University, Melbourne, Victoria, Australia.
authors.forename: David W
authors.initials: DW
authors.lastname: Dunstan
authors.affiliation: Cancer Prevention Research Centre, School of Population Health, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Elizabeth G
authors.initials: EG
authors.lastname: Eakin
authors.affiliation: School of Health and Life Science, Institute of Applied Health Research, Glasgow Caledonian University, Glasgow, UK.
authors.forename: Sebastien F M
authors.initials: SF
authors.lastname: Chastin
authors.affiliation: Cancer Prevention Research Centre, School of Population Health, The University of Queensland, Brisbane, Queensland, Australia Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia Faculty of Health Sciences, School of Physiotherapy, Curtin University, Perth, Western Australia, Australia.
authors.forename: Genevieve N
authors.initials: GN
authors.lastname: Healy
mesh_terms: D000328:Adult; D015444:Exercise / Q000502:physiology; D005260:Female; D015438:Health Behavior; D006293:Health Promotion / Q000379:methods*; D006801:Humans; D008297:Male; D018670:Monitoring, Ambulatory / Q000379:methods; D016272:Occupational Health; D010865:Pilot Projects; D057185:Sedentary Behavior; D013997:Time Factors; D017132:Workplace
keywords: Intervention effectiveness; Physical activity measurement