Sedentary behavior has been proposed as a risk factor for obesity that is distinct from physical inactivity. This study aimed to examine the association between occupational sedentary behavior and obesity, and to determine if this association is independent of leisure-time physical activity (LTPA).
Fully employed participants enrolled between 2001 and 2008 to Alberta’s Tomorrow Project, a prospective cohort study in Alberta, Canada, were studied (n = 12,409). Associations between occupational sedentary behavior and waist circumference (WC), waist-to-hip ratio (WHR), and body mass index (BMI) were examined using multiple binary and multinomial logistic regressions.
In men, a positive association was observed between daily occupational sedentary hours and WC, WHR, BMI, and with high risk profiles that incorporated both BMI and WC (P < .01). Controlling for vigorous-intensity LTPA in all models strengthened associations between sedentary behavior and measures of obesity. In contrast, inverse associations were observed for occupational sedentary hours and WHR for women (P < .05).
In fully employed men, occupational sedentary behavior was positively associated with obesity risk that was not attenuated by physical activity. In women, an increase in obesity risk was not observed with sedentary behavior. Gender differences in the health effects of sedentary behavior require further study.
Nicholas (email@example.com) is with the University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada. Lo Siou is with the Dept of Cancer Measurement, Outcomes, Research, and Evaluation (C-MORE), CancerControl Alberta, Alberta Health Services, Calgary, Alberta, Canada. Lynch is with The Cancer Epidemiology Center, Cancer Council Victoria, Melbourne Australia. Robson is with the Dept of Cancer Measurement, Outcomes, Research, and Evaluation (C-MORE), Cancer-Control Alberta, Alberta Health Services, Edmonton, Alberta, Canada. Friedenreich and Csizmadi are with the Dept of Cancer Epidemiology and Prevention Research, CancerControl Alberta, Alberta Health Services, Calgary, Alberta, Canada.