The effects of occupational and leisure time physical activity on health-related quality of life: a repeated-measures longitudinal study

Background: High leisure time physical activity (LTPA) is consistently linked to health benefits, whereas high occupational physical activity (OPA) has been associated with adverse health outcomes, a phenomenon known as the "physical activity health paradox." This study examined how OPA and LTPA interact to influence health-related quality of life (HRQL), a measure of physical and mental well-being. Methods: A repeated-measures longitudinal study was conducted using data from 7382 Canadian workers (aged 18-75 years) in the National Population Health Survey (1994-2011). Multilevel growth curve models were used to assess associations between self-reported measures of LTPA (active, inactive), OPA (sit, walk/light loads, heavy loads), and OLTPA, a composite variable of their combined effects, with the Health Utility Index score (HRQL), adjusting for sociodemographic and health covariates. Results: Active LTPA was associated with better HRQL, whereas OPA was not. Results suggested a curvilinear response between OLTPA and HRQL with age whereby middle-aged workers lifting heavy loads at work and active LTPA have lower HRQL than older workers in the same group. Findings were similar among males, but among older females (60 + years) who lifted heavy loads at work, being inactive rather than active in leisure resulted in higher HRQL. Conclusion: The association between LTPA, OPA, and HRQL is complex, varying across age and sex. These findings highlight the need for physical activity recommendations that are sensitive to occupational demands when promoting health and well-being.