Abstract
Leisure physical activity is considered protective against several cancers, but the impact of physical activity at work remains unclear. We analyze data from over 400,000 Norwegian adults followed for a median of 27 years to examine how different levels of occupational physical activity are associated with cancer incidence and mortality. Participants report their typical work activity as sedentary, walking, walking-and-lifting, or heavy labor. Here we show that individuals with more physically active jobs have a lower risk of developing several cancers (i.e., endometrial, colon, breast, rectal, and prostate), and to a lesser extent, the risk of breast cancer mortality. However, occupational physical activity is also associated with increased risk of esophageal and kidney cancer death. These findings suggest that occupational physical activity may lower the incidence of some cancers but are associated with a higher mortality from other cancer types. Understanding these patterns could help tailor public health recommendations related to physical activity and occupational health.