RACHEL MARTIN, HOST:
You probably know this intuitively, but now there is more evidence finding that too much sitting is harmful to your health. It's linked to obesity, high blood pressure and an increased risk of heart disease. Now there's a new study suggesting that not all sitting is created equal, and some types may be more dangerous than others. Here's NPR's Patti Neighmond.
PATTI NEIGHMOND, BYLINE: Many of us sit at work. We go home, and many of us sit there, too. Researchers wanted to know if both types of sitting were equally harmful. They asked more than 3,500 adults to report over eight years how much they sat at home and at work. Lead researcher Keith Diaz is an exercise physiologist at Columbia University Irving Medical Center.
KEITH DIAZ: Individuals who watched four or more hours of TV a day had a 50% greater risk of heart disease compared to individuals who watched TV less than two hours a day.
NEIGHMOND: Makes sense - the longer you sit, the greater your risk. But here's the surprising part.
DIAZ: Sitting at work was not associated with risk of heart attack or stroke.
NEIGHMOND: Those who sat the most at work had no greater health risk than those who sat the least. So it was TV sitting that was the culprit. Diaz doesn't know why exactly, but speculates it could be other activities that may go along with TV viewing.
DIAZ: The typical American eats a large meal dinner and then sits on the couch and watches TV for hours at a time. And we think that's a toxic combination of eating a large meal and then sitting for the rest of your evening.
NEIGHMOND: And maybe snacking, particularly on junk food. Diaz says it could also have something to do with how we sit when we watch TV.
DIAZ: So when we watch TV, we sit for hours at a time. We sit for three, four hours at a time without moving versus at work. Many individuals - they're getting up and going to the printer, to a copy machine, to a coworker's desk.
NEIGHMOND: These short interruptions of activity, he says, might just be enough to offset the risks of sitting. And regular exercise also made a big difference. For people who exercised at least 30 minutes, five days a week, there was no increased health risk, even if they sat and watched TV for four hours or more. Now, all participants in the study were African Americans, which is particularly important, says Dr. Martha Gulati with the American College of Cardiology.
MARTHA GULATI: We know that African Americans have a higher risk of cardiovascular disease at all ages, and we also know that they have a lower life expectancy compared to Caucasians.
NEIGHMOND: And, she says, the take-home advice from these findings for all races is clear.
GULATI: Reducing the amount of television we watch is one way to start making changes.
NEIGHMOND: And if you enjoy binge-watching and just can't stop...
GULATI: Maybe it's more important to figure out a way to move at home rather than us putting, you know, the standing desks and walking treadmills at work.
NEIGHMOND: Another option, says Dr. Felipe Lobelo with the American Heart Association, is take short breaks from TV-watching time.
FELIPE LOBELO: Even if you're not getting up to exercise - but if you're breaking those two or three hours of sedentary time into, say, chunks of 20 minutes, and every 20 minutes, you get up and make a phone call or just simply move, that has a potential benefit.
NEIGHMOND: So whenever you're sitting for long periods of time, get up now and then. It's good for your heart. Patti Neighmond, NPR News. Transcript provided by NPR, Copyright NPR.