SECOND OPINION | Long flight? Staying home and binge watching TV? Risk of deep vein thrombosis either way

That deep vein thrombosis risk you've heard about on long flights? It can also happen after binge watching TV, researchers say.

If you can't pull yourself away from the TV, then break up the sitting time with jumping jacks

People are encouraged to break up long periods of sitting. (Shutterstock)

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That deep vein thrombosis risk you've heard about on long airline flights? It can also happen after binge watching TV.

If you're planning to spend a lot of quality time in front of your TV this weekend, you may want to move around a little.

Research published this week in the Journal of Thrombosis and Thrombolysis found that spending hours blowing through a season of Black Mirror or Stranger Things increases your chances of developing a potentially fatal blood clot.

Study subjects who reported that they watched television "very often" carried a 95 per cent higher risk of developing venous thromboembolism (VTE), a condition where clots form in the lower legs. Those clots are known as deep vein thrombosis, which — as you've probably heard — has previously been linked to long-distance air travel.

Lead author Yasuhiko Kubota, now chief physician at Osaka Center for Cancer and Cardiovascular Prevention in Japan, said he embarked on this research out of concern about the impact of our couch-potato ways.

"More and more people all over the world are physically inactive, and they are more likely to have lifestyle diseases such as cardiovascular disease," said Kubota. "Particularly, TV viewing appears to contribute to being sedentary for a long time."

While researching at the University of Minnesota, Kubota and his colleagues examined data from 15,158 Americans between the ages of 45 and 64 who were part of a larger study started in 1987.

While the researchers didn't examine the exact mechanism of how clots form during screen binges, it's likely that when you're marooned on the sofa for hours on end, blood flow back to the heart from the legs and feet is impaired, said Kubota.

Exercise doesn't provide insurance

While beneficial overall, working out regularly didn't lower the risk of VTE among those study subjects who reported watching the most amount of TV. Even meeting the recommended level of physical activity was no insurance, the study found.

"Of course, exercise is very important. But, rather than a vigorous workout, I believe it is more important to move around or move legs during TV viewing," said Kubota.

A fan of news and history programs, Kubota says this and other research has prompted him to avoid binge watching for the most part. "If I want to watch TV for a long time, I try to move regularly."

If you can pull yourself away in between episodes, then spend 60 seconds vigorously ascending and slowly descending a single flight of stairs.- Martin Gibala

A little movement during your TV marathon can indeed help to get the blood circulating, said Martin Gibala, a professor of kinesiology at McMaster University in Hamilton, Ont., and author of The One-Minute Workout

"If you can't pull yourself away from the television, then break up the sitting time during an hour-long show with a few sets of jumping jacks or air squats," said Gibala.

"If you can pull yourself away in between episodes, then spend 60 seconds vigorously ascending and slowly descending a single flight of stairs."

This approach could lower your risk of a blood clot and get you fitter, too.

"The bottom line is anything is better than nothing, and breaking up prolonged periods of sitting with a some short bouts of physical activity involving large muscle groups is beneficial for your health."

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About the Author

Brandie Weikle

CBC News

Brandie Weikle is a senior writer for CBC News based in Toronto. She's a long-time magazine and newspaper editor and podcast host with specialities in parenting and health. You can reach her at brandie.weikle@cbc.ca.