Study Finds That People Who Sit the Most Seem to Die Earlier Than Others

Tuesday, May 12, 2009

If you sit for too long, you'll die. Or at least you may die earlier than those who get up and move around during the day, according to a study published in this month's issue of Medicine & Science in Sports & Exercise.

The study explored the relationship between sedentary behavior (that is, sitting) and premature mortality by observing a group of more than 17,000 Canadians ages 18 to 90 who took part in the 1981 Canada Fitness Survey. Survey participants rated themselves on how much time they spent sitting in any given week: almost none of the time, a fourth of the time, half of the time, three-fourths of the time, and almost all of the time. During the 12 years that the study followed the subjects, 1,832 of them died. The researchers found that the mortality rate was almost three times higher among the least active than it was among the most active.

The effects were consistent regardless of sex, age, smoking status and body mass index. And they were "independent of leisure time physical activity," the researchers said. In other words, sedentary behavior is not the same as lack of exercise; even physically fit people who exercised regularly still seem to risk premature death if they sit for prolonged periods during the day.

The authors noted that people in the United States "spend an average of 55 percent of their day in sedentary pursuits" such as watching TV, eating, working at a desk and riding in a car. "In addition to the promotion of moderate-to-vigorous physical activity and a healthy weight, physicians should discourage sitting for extended periods," the authors wrote.

Those extended periods, they said, result in "metabolic alterations" that cannot be compensated for even if the individual exceeds the daily minimum physical activity guidelines of the American Heart Association.

To reduce your chances of premature mortality by sitting, the authors said, increase your level of daily physical activity and reduce the time you spend sitting per day by taking breaks every 60 to 90 minutes.

-- Benjamin Opipari

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