Associations of physical activity at work and household income with obesity: a cross-sectional study among rural adults in Korea

OBJECTIVES: This study was performed to identify the effect of physical activity at work on obesity and to analyze the contribution of socioeconomic factors and health behaviors to this association, which has been relatively little studied. METHODS: From the Korean National Cancer Center Community Cohort, a total of 5,587 adults (2,125 men; 3,462 women) aged more than 30 years living in rural areas were enrolled. Information on socio-demographic factors, health behaviors, and body mass index was gathered using face-to-face interviews and measurements of height and weight. RESULTS: Inverse associations were identified between vigorous-intensity physical activity at work and obesity in both men and women, while no association was found between vigorous-intensity physical activity during leisure time and obesity. High household income was independently associated with a lower risk of obesity among those who had low levels of vigorous-intensity physical activity at work. Vigorous physical activity at work showed an inverse association with obesity in rural areas where heavy manual labor is common. CONCLUSIONS: Our findings indicate the necessity to account for various types of physical activity to improve the assessment and prevention of obesity.