title: Chronic workplace stress and insufficient physical activity: a cohort study.
abstract: OBJECTIVE
  To examine whether exposure to workplace stressors predicts changes in physical activity and the risk of insufficient physical activity.
  
  
  METHODS
  Prospective data from the Finnish Public Sector Study. Repeated exposure to low job control, high job demands, low effort, low rewards and compositions of these (job strain and effort-reward imbalance) were assessed at Time 1 (2000-2002) and Time 2 (2004). Insufficient physical activity (<14 metabolic equivalent task hours per week) was measured at Time 1 and Time 3 (2008). The effect of change in workplace stressors on change in physical activity was examined using fixed-effects (within-subject) logistic regression models (N=6665). In addition, logistic regression analysis was applied to examine the associations between repeated exposure to workplace stressors and insufficient physical activity (N=13 976). In these analyses, coworker assessed workplace stressor scores were used in addition to individual level scores.
  
  
  RESULTS
  The proportion of participants with insufficient physical activity was 24% at baseline and 26% at follow-up. 19% of the participants who were sufficiently active at baseline became insufficiently active at follow-up. In the fixed-effect analysis, an increase in workplace stress was weakly related to an increase in physical inactivity within an individual. In between-subjects analysis, employees with repeated exposure to low job control and low rewards were more likely to be insufficiently active at follow-up than those with no reports of these stressors; fully adjusted ORs ranged from 1.11 (95% CI 1.00 to 1.24) to 1.21 (95% CI 1.05 to 1.39).
  
  
  CONCLUSIONS
  Workplace stress is associated with a slightly increased risk of physical inactivity.
authors.affiliation: School of Sociology, Social Policy & Social Work, Queen’s University Belfast, Belfast, UK and Centre of Excellence for Public Health (NI), Queen’s University Belfast, Belfast, UK. a.kouvonen@qub.ac.uk
authors.forename: Anne
authors.initials: A
authors.lastname: Kouvonen
authors.forename: Jussi
authors.initials: J
authors.lastname: Vahtera
authors.forename: Tuula
authors.initials: T
authors.lastname: Oksanen
authors.forename: Jaana
authors.initials: J
authors.lastname: Pentti
authors.forename: Ari K P
authors.initials: AK
authors.lastname: Väänänen
authors.forename: Tarja
authors.initials: T
authors.lastname: Heponiemi
authors.forename: Paula
authors.initials: P
authors.lastname: Salo
authors.forename: Marianna
authors.initials: M
authors.lastname: Virtanen
authors.forename: Mika
authors.initials: M
authors.lastname: Kivimäki
mesh_terms: D000328:Adult; D004651:Employment; D015444:Exercise; D005260:Female; D005387:Finland; D006801:Humans; D016015:Logistic Models; D008297:Male; D055686:Metabolic Equivalent; D008875:Middle Aged; D016273:Occupational Exposure; D011446:Prospective Studies; D012201:Reward; D013315:Stress, Psychological / Q000150:complications*; D017132:Workplace