Prolonged Standing at Work Linked to Increased CV Risk
According to a large Canadian survey, workers who must stand for most of the day are at much higher risk than sedentary office workers.
The negative health effects associated with a sedentary lifestyle are well-documented, but a new study suggests that standing for long stretches throughout the workday puts people at greater risk for heart disease than sitting down on the job.
The 12-year study of Canadian workers found that people in occupations that require prolonged standing, such as retail salespersons, cooks, and machine operators, are much likely to develop cardiovascular disease than those who work office- or driving-based jobs that require mostly sitting.
“There is a general perception, which is true, that being sedentary is bad for your health,” lead author Peter Smith, PhD (Institute for Work & Health, Toronto, Canada), told TCTMD. “People have extrapolated that to mean the amount of sitting we do at work is the main cause of all this and that maybe we should all stand a bit more. But standing does not give you the type of cardiovascular workout you need to reduce your risk of heart disease.”
Smith said biological mechanisms largely explain why standing in a fixed place for hours at a time is actually worse for your health in the long term than sitting down. “The blood tends to pool in your legs, there is an increase in venous tension and oxidative stress, all of which increase the risk for cardiovascular disease,” he noted. “Combinations of standing and sitting and walking are probably where we need to be for all types of occupations.”
The study, which was published online recently in the American Journal of Epidemiology, followed 7,320 participants of the Canadian Community Health Survey. All reported working 15 hours a week or more and were free of cardiovascular disease at baseline. In addition to sitting and standing jobs, the study also looked at people whose occupations required a combination of the two (ie, nurses, delivery drivers, teachers, cashiers) and those required to be in other body positions throughout the work day (ie, nurse aides, orderlies, mechanics, janitors).
Over the study period from 2003 to 2015, 3.4% of the population developed cardiovascular disease—4.6% of men and 2.1% of women. After adjustment for sociodemographic, health, and work-related variables, people with predominantly standing occupations had twice the risk of developing new cardiovascular disease compared with those in mostly sitting jobs (HR 2.18; 95% CI 1.11-4.27). The findings remained robust in a variety of models attempting to account for confounders.
The findings also were consistent between men and women in terms of a greater harm from standing versus sitting jobs, although men but not women had less risk of cardiovascular disease if they were in occupations that required a combination of sitting, standing, and walking.
Improving Disease-Prevention for Those at Risk
Smith said the researchers were unable to determine a threshold for the length of time spent standing that is more harmful, adding that there is likely to be some variation from one person to another, even among those in the same occupation. He observed that having people wear monitors that track their sitting and standing might be one way to attempt to look at this in future studies.
“This study draws attention to the fact that work does play a role in the development of cardiovascular disease and we need to focus better on the things that may increase risk,” Smith told TCTMD. “We need to raise awareness that prolonged standing is a risk factor, and it’s actually quite an easy risk factor to modify. You can provide people with breaks and opportunities to sit . . . through things such as job rotation, or providing stools to people to sit down on the job. There’s no real reason why someone who works in retail sales, for example, has to remain standing throughout the day. We don’t often think about these work-related things and how they affect chronic disease, but this may be something where we can integrate the findings in our disease-prevention programs.”
So, is it time for enthusiasts to break up with their standing desks? “There is a real absence of evidence that standing for short periods does anything to reduce your risk of cardiovascular disease,” Smith noted. “The best thing to do is to be more active during the day rather than think that just standing a few extra hours will make any difference. Now, some people may benefit from these desks if they have back pain, or feel that it improves their concentration and creativity, but for long-term health, there is no high-quality evidence.”
Smith P, Ma H, Glazier RH, et al. The relationship between occupational standing and sitting and incident heart disease over a 12-year period in Ontario, Canada. Am J Epidemiol. 2017;Epub ahead of print.
- Smith reports no relevant conflicts of interest.