The researchers focused on two categories of health outcomes: cardiovascular, covering coronary heart disease, heart failure, and stroke; and orthostatic circulatory disease events, including orthostatic hypotension (blood pressure drops upon standing or sitting), varicose veins, chronic venous insufficiency (veins in your legs don’t move blood back up to your heart), and venous ulcers. The reasoning for this second category is that prolonged sitting and standing may pose risks for developing circulatory diseases.
The researchers found that when participants’ total stationary time (sitting and standing) went over 12 hours per day, risk of orthostatic circulatory disease increased 22 percent per additional hour, while risk of cardiovascular disease went up 13 percent per hour.
For just sitting, risks increased every hour after 10 hours: for orthostatic circulatory disease, risk went up 26 percent every hour after 10 hours, and cardiovascular disease risk went up 15 percent. For standing, risk of orthostatic circulatory disease went up after just two hours, increasing 11 percent every 30 minutes after two hours of standing. But standing had no impact on cardiovascular disease at any time point.
“Contrary to sitting time, more time spent standing was not associated with a higher CVD [cardiovascular disease] risk. Overall, there was no association for higher or lower CVD risk throughout the range of standing duration,” the authors report.
On the other hand, keeping sitting time under 10 hours and standing time under two hours was linked to a weak protective effect against orthostatic circulatory disease: A day of nine hours of sitting and 1.5 of standing (for a total of 11.5 hours of stationary time) lowered risk of orthostatic circulatory disease by a few percentage points, the study found.
In other words, as long as you can keep your total stationary time under 12 hours, you can use a little standing time help you keep your sitting time under 10 hours and avoid increasing both cardiovascular and orthostatic risks, according to the data.
Consistent finding
It’s a very detailed formula to reduce the health risks of long days at the office, but is it set in stone? Probably not. For one thing, it’s just one study that needs to be replicated in a different population. Also, the study didn’t look at any specifics of occupational versus leisure standing and sitting times, let alone the use of standing desks specifically. The study also based estimates of people’s sitting, standing, and total stationary time on as little as just four days of activity monitoring, which may or may not have been consistent over the nearly seven-year average follow-up period.
