Sitting and other sedentary behaviors are so hazardous to health that adults should significantly limit the time they are inactive to stave off heart disease and stroke, a special American Heart Association panel said in a report published Monday.
The state of being sedentary — not only a lack of exercise — is a potentially independent risk factor for cardiovascular disorders, the 11-member advisory panel of physicians and public health experts said.
“Regardless of how much physical activity someone gets, prolonged sedentary time could negatively impact the health of your heart and blood vessels,” Deborah Rohm Young, the group’s chairwoman, said in a statement.
The report, in the weekly journal Circulation, defines sedentary behaviors as sitting, reclining or lying down while awake. Other activities under the behavioral umbrella include working at a computer, watching television and reading.
The research is part of a growing body of scientific investigation into whether sitting is “the new smoking” in terms of health risks, and whether sedentary behaviors escalate the potential for a variety of medical conditions.
While the heart association’s panel focused on increased risk of cardiovascular disorders, the findings suggested a heightened risk of diabetes among those who are sedentary because their insulin activity is less efficient. The panel also proposed that extended periods of inactivity raise the risk of death from all causes.
Aside from the new report, doctors studying the ill effects of sitting have highlighted other possible risks.
For example, cancer researchers have connected sedentary lifestyles to an increased possibility of certain malignancies. And four years ago, a team of British scientists linked chronic kidney disease to sitting eight or more hours daily. Poor kidney function was determined by high levels of a telltale protein — albumin — in urine tests.
“There are many important factors we don’t understand about sedentary time yet,” said Young, director of behavioral research at Kaiser Permanente in Pasadena, California. “We don’t have information about how much sedentary behavior is bad for health. The best advice at this time is to sit less and move more.”
People who are physically active must take into account how much time they spend simply sitting or otherwise inactive to reap the true benefits of their exercise, the panel said.
On Long Island, Dr. Barbara George, who directs the Center for Cardiovascular Lifestyle Medicine at Winthrop-University Hospital in Mineola, said the average workplace and many pursuits at home often involve hours spent being sedentary.
“We’ve become a sedentary society — sitting in front of a computer, driving, watching TV. All of this amounts to six to eight hours daily of sitting. That’s about average for adults,” George said, citing the newly reported data. “We really want to get that down to four to five. That’s what we’re shooting for.”
In a sitting position, the body burns fewer calories, she said, because metabolism is slower while seated when compared with standing.
George — saying “I try to practice what I preach” — works at a desk that allows her to stand during much of her workday. The desk can be easily lowered to accommodate the moments she allows herself to sit.
Her phone habits also help her stay active. “I walk and talk,” she said. “I don’t sit and speak.”
In the workplace, George recommended conducting meetings while walking as one way to reduce the amount of time spent sitting. Meetings held while on the move tend to be more productive, with fewer distractions, she said.
At home, exercising while watching TV is another way to turn a sedentary activity into an active one, she said.
Findings and remedies
- Sitting and other sedentary behavior may increase the risk of cardiovascular disease, diabetes and overall risk of death.
- Adults under age 60 spend six to eight hours of sedentary time daily; those above that age spend 8.5 to 9.6 hours seated, reclining or lying down.
- Heart association panel recommends 30 minutes of moderate to vigorous exercise daily. To truly reduce health risks, the group recommends reducing the amount of time spent sedentary.
- If you sit at your job, set an alarm on your cellphone as a reminder to stand up at least every two hours for more than a minute to walk, bend and stretch.
- Gradually reduce daily sitting time by 15 to 20 minutes, aiming for two to three fewer sedentary hours over a 12-hour day.
Sources: American Heart Association Science Advisory Panel; Dr. Barbara George, Winthrop-University Hospital