Association between passive jobs and low levels of leisure-time physical activity: the Whitehall II cohort study

Background: There is mixed evidence on the association between psychosocial work exposures (ie, passive jobs) and physical activity, but previous studies did not take into account the effect of cumulative exposures nor did they examine different trajectories in exposure. We investigated whether exposure to passive jobs, measured three times over an average of 5 years, is associated with leisure-time physical activity (LTPA). Methods: Data were from working men (n=4291) and women (n=1794) aged 35-55 years who participated in the first three phases of the Whitehall II prospective cohort. Exposure to passive jobs was measured at each phase and LTPA at phases 1 and 3. Participants were categorised according to whether or not they worked in a passive job at each phase, leading to a scale ranging from 0 (non-passive job at all three phases) to 3 (passive job at all three phases). Poisson regression with robust variance estimates were used to assess the prevalence ratios of low LTPA. Results: An association was found in men between exposure to passive jobs over 5 years and low LTPA at follow-up, independently of other relevant risk factors. The prevalence ratio for low LTPA in men was 1.16 (95% CI 1.01 to 1.33) times greater for employees with three reports of passive job than for those who had never worked in passive jobs. No association was observed in women. Conclusion: This study provides evidence that working in passive jobs may encourage a passive lifestyle in men.