Health content producer Chelsea Rice stands at her desk in the Globe newsroom.
Did you know that the average 70-year-old woman spends two-thirds of her waking hours in a sedentary position? I’m guessing most journalists in the Boston Globe newsroom do as well—though more of us are trying to avoid sitting by using standing desks like my colleague in the photo above.
Sitting has become the new smoking in terms of bad health habits. Researchers are racing to determine how much is too much and, more importantly, what we can do about it.
In a new study published Tuesday in the Journal of the American Medical Association, Boston researchers analyzed sedentary behaviors in more than 7,200 elderly women who wore accelerometers to measure how often they moved each day for a week. While the study confirmed previous research suggesting that older folks spend most of their time inactive, it also found that they don’t sit for very long without getting up to move around a bit.
“I was kind of surprised to see that study participants spent only 30 percent of their time sitting around for longer than 30 minutes,” said study leader Eric Shiroma, a researcher at Brigham and Women’s Hospital.
Of course, they may have made a concerted effort to get up and move around more than usual knowing they were wearing an accelerometer for a study. The researchers couldn’t control for that, nor did they look long term to see whether excess sitting was linked to poorer health. “That’s what we’re looking at next,” Shiroma said.
He’d also like to tweak the accelerometers a bit to enable them to distinguish between sitting and standing in a sendentary position—something the devices didn’t do in the study. (The researchers believe the participants were sitting most of the time they were sedentary.)
“Some preliminary data suggest that standing is better for the health than sitting,” Shiroma said, “but those studies have often been funded by standing desk manufacturers.”
He admitted that scientists are “just starting to scratch the surface” of research into sedentary lifestyle habits.
For example, they know how much exercise we need to keep our hearts, minds, and bodies strong: 150 minutes of moderate activity or 75 minutes of vigorous activity per week. They also know that some of these benefits get wiped out if we sit and don’t move enough the rest of the day.
But there aren’t any specific recommendations to let us know the maximum time we should be in a state of rest, nor whether it’s better to get up and walk for two minutes every half-hour or for five minutes every hour.
“We’ve got a lot of good questions,” Shiroma said, “now we need to start answering some of them through research.”