Sitting at Work

Sitting at work raises the risk of dying from cardiovascular (CV) and metabolic diseases, as well as the risk of dying from all causes, regardless of any exercise in which the individual may engage. That was the finding of a study reported at the 19th European Congress on Obesity (ECO) by the Prevention Research Collaboration in the School of Public Health at the University of Sydney, Australia.

Research is increasingly focusing on sedentary behavior with low energy expenditure, including sitting and lying down, as behavioral risk factors for obesity and chronic disease. Sitting occurs during travel, while watching television, using computers, and reading. But with people often spending at least 9 hours a day at work, with fewer than 20% of jobs requiring physical exertion, and with many people spending at least 4 hours a day sitting at work, the sedentary time at work is high, and many people are affected.

The investigators therefore aimed to evaluate the relationship between occupational sitting, body mass index (BMI), and mortality in a general population sample. Between 1995 and 1997, 20-year-old subjects self-reported their level of sitting at work. Of 45,259 participants completing the study (evenly divided between men and women), just over 40% each were either of normal weight or were overweight, and about 15% were obese. During a follow-up period of 12 to 14 years, 4421 died. Sedentary work was associated with higher all-cause mortality and CV/metabolic disease mortality compared with occupations with much walking, much walking or lifting, or heavy physical labor.

"Holding all else equal, someone with an occupation that involved walking and lifting had a 27% lower chance of dying than someone who mostly sat in their occupation among those in the obese category," researchers said. The curves for CV mortality showed a similar pattern.

"You can do a lot of desk work actually standing. You can do meetings standing, or you could vary so that you're not sitting all the time but actually taking a break to stand, and that would be the immediate recommendation taken out of this," researchers said. "The tone from the muscles from standing is expending energy and may actually be contributing to the healthy factors about not sitting."