For those of us who have resolved to stand more and sit less in the coming year, a new study might temper some of our expectations of the benefits.
It finds that people burn more calories when they stand than when sitting or lying down, but the increase is smaller than many of us might hope. For those of us who overindulged and slacked off on our exercise regimens over the holidays, it also means that being upright is unlikely to help us lose weight.
But it does not mean we should take this news lying or sitting down, the study’s authors caution, because frequent standing is likely to have other, substantial health impacts.
By now, almost everyone has heard about, dabbled with or rolled their eyes at the phenomenon of standing desks. Many of us also wear fitness trackers that nag us every hour or so to get up and move.
Science generally supports this rising interest in not sitting. Studies in animals and people show that long hours of stillness change the body’s physiology in multiple unhealthy ways, including reducing blood flow to the legs and brain; worsening the health of blood vessels; and lowering the production of substances that help to control cholesterol and blood sugar.
In consequence, being sedentary can increase our risks for diabetes, heart disease and premature death.
Lots of sitting also is linked with heightened odds of obesity and, for many of us, it is this association that is most worrying and most likely to prompt us to stand.
And, again, past studies have been encouraging, with most indicating that we should expend hundreds of additional calories when we stand often rather than sit.
But many of these experiments have involved somewhat exaggerated behaviors, such as absolute stillness while people sat, with no wriggling or fidgeting, and walking about or performing chores during the upright portions.
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.
But there are caveats to that discouraging conclusion. Perhaps most interesting, some people burned more calories than others while seated and standing, because they fidgeted so much. Those people also tended to report exercising regularly.
It’s possible, Dr. Betts says, that “people who are physically fitter and more active may have a greater propensity to fidget.”
It’s also possible that people who do not naturally fidget might slightly ramp up their energy expenditure during sitting and standing if they wriggle, jounce and ignore remonstrations from their spouses and co-workers to just stay still.
More important, Dr. Betts says, “while standing does not represent an effective weight-loss strategy,” it might help some people to avoid adding weight. That’s because even small energy surpluses — consuming a few more calories each day than you expend — can contribute to long-term weight gain and obesity.
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