Scientists at the University of Bath in England and Westmont College in California suspected that these methods wound up inflating the spread in energy expenditure between being sedentary and upright.
So for the new study, which was published in November in Medicine & Science in Sports & Exercise, they decided to ask people to sit and stand more naturally and to closely monitor how many calories they burned in the process. They began by recruiting 46 men and women whose weight was normal. Ten were Californians; the rest British. The researchers asked these volunteers about their health and exercise habits and then determined their average daily energy expenditure by fitting them with masks that measured their metabolic rate.
They then had each of the volunteers lie down, sit or stand for 20 minutes at a time, on separate lab visits, while wearing the masks. To stave off boredom, the volunteers watched a soothing BBC nature documentary during each session.
They also were allowed to bounce, wiggle, bobble or otherwise fidget as much or little as they wished during the sessions. They were asked, though, to remain in place while upright, as someone would if working at a standing desk.
Then the researchers compared the number of calories they had burned in each posture.
The differences were noticeable. But they also were small. As a group, the volunteers burned about 3 percent more calories when sitting compared to lying down and about 12 percent more standing compared to sitting.
In more practical terms, the researchers estimate that, based on their metabolic findings, most people could expect to burn about 9 additional calories if they stood for an hour instead of sitting and, if they doubled that standing time to two hours a day, would burn about 130 extra calories over the course of a week.
Realistically, those totals “would not result in sufficient energy deficit to drive a worthwhile rate of weight loss,” says James Betts, a professor of health research at the University of Bath, who led the study.