A team of researchers in the Mass General Brigham health care system showed that an excessively sedentary lifestyle—spending most of your waking hours sitting, reclining, or lying down—corresponds to an increased risk of heart disease, namely heart failure and death. However, the meeting of exercise guidelines alone may not lessen those odds. Their findings were published Nov. 15 in the Journal of the American College of Cardiology.

“Many of us spend the majority of our waking day sitting, and while there’s a lot of research supporting the importance of physical activity, we knew relatively little about the potential consequences of sitting too much beyond a vague awareness that it might be harmful,” Dr. Ezimamaka Ajufo, a cardiology fellow at Brigham and Women’s Hospital and lead author of the study, said in a news release about the research.

“Sedentary risk remained even in people who were physically active, which is important because many of us sit a lot and think that if we can get out at the end of the day and do some exercise we can counterbalance it. However, we found it to be more complex than that.”

Ajufo and her colleagues used the U.K. Biobank health database to track the daily activities of nearly 90,000 people over the course of a week. Study participants were 56% women, with an average age of 62. Researchers documented their time spent asleep, sedentary, doing light activity, and doing moderate to vigorous activity. They split them into four groups, based on inactivity:

• More than 10.6 sedentary hours a day
• 9.4–10.6 sedentary hours a day
• 8.2–9.4 sedentary hours a day
• Fewer than 8.2 sedentary hours a day

Participants who spent the least time sitting not only spent the most time being active but also got the most sleep, while those who spent the most time sitting got the least amount of sleep and were the least active.

Sitting 10+ hours per day is most dangerous to heart health

Researchers assessed participants’ health a median eight years after their physical activity had been recorded, focusing on those who had developed these heart conditions:

• Atrial fibrillation
• Cardiovascular mortality (death)
• Heart failure
• Myocardial infarction (heart attack)

Sedentary behavior correlated to an increased risk of all of the above ailments. What’s more, people in the most inactive group, who recorded more than 10.6 sedentary hours a day, had a 40% to 60% greater risk of heart failure and cardiovascular death than those in the 8.2- to 9.4-hour group.

“Our data supports the idea that it is always better to sit less and move more to reduce heart disease risk, and that avoiding excessive sitting is especially important for lowering risk of heart failure and cardiovascular death,” co-senior author Dr. Shaan Khurshid, a cardiac electrophysiologist at Massachusetts General Hospital, said in the news release.

The latest Physical Activity Guidelines for Americans recommend adults get at least 75 to 150 minutes of vigorous aerobic activity or 150 to 300 minutes of moderately intense aerobic activity each week, in addition to two days of muscle-strengthening exercises. But even study participants who achieved the aerobic recommendations weren’t immune from the detriments of a sedentary lifestyle. Exercise could mostly mitigate the risks of heart attacks and atrial fibrillation, researchers noted, but only partially quash those of death and heart failure.

Study limitations include the relatively brief monitoring period; one week may not have accurately captured participants’ long-term physical activity habits. In addition, it’s possible the wrist-worn activity trackers may misclassify standing time as sedentary time, the authors wrote. They plan to expand their research to study how sedentary behavior relates to other diseases over longer periods of time.

“Exercise is critical, but avoiding excessive sitting appears separately important,” co-senior author Dr. Patrick Ellinor, a cardiologist and codirector of the Corrigan Minehan Heart Center at Massachusetts General Hospital, said in the news release. “Our hope is that this work can empower patients and providers by offering another way to leverage movement behaviors to improve cardiovascular health.”

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How to move more, sit less

You don’t have to join a gym or stand up all day to live a less sedentary lifestyle. The American Heart Association recommends these tips for weaving more movement into your day:

1. Set a timer. Avoid being sedentary for too long and set a reminder to move around for five minutes every hour or 10 minutes every two hours.
2. Be creative at home. Find more ways to get up and off the couch by taking a walk or doing a few push-ups between episodes of a TV show. Active chores like vacuuming and cleaning up after dinner count too.
3. Don’t wait. Make it a habit to work out right after work or school. Check out these videos that you can do from home.
4. Find forms of exercise you like. Experiment with workouts that fit your personality and schedule. You’ll be more likely to stick with it.
5. Move more while working. Make it a habit to stand every time you make or answer a phone call or add stretch breaks between tasks.

For more on overcoming sedentary behavior:

• Too much sitting increases your risk of death by 38%. How ‘exercise snacks’ may help
• A CDC map shows that a quarter of Americans were too sedentary, even before COVID. See how your state ranks
• Sorry, Netflix binge-watchers. Too much TV may be cutting your lifespan
• Working out at these times of day could reduce your risk of colorectal cancer by 11%, new study says
• Strokes are on the rise, especially in younger people. These 5 lifestyle changes can help lower your risk