Exercise Won't Erase Sitting Risks

Prolonged sitting is a health hazard even when people exercise regularly, a new Canadian

has found.

study

Writing in

, David Alter, MD, PhD, and colleagues quantified the association between sedentary time and negative health outcomes. Those included hospitalizations, mortality, cardiovascular disease, diabetes and cancer in adults.

Annals of Internal Medicine

The team looked at published studies assessing sedentary behavior in adults, adjusted for physical activity and correlated to at least 1 outcome.

“Despite the health-enhancing benefits of physical activity, this alone may not be enough to reduce the risk for disease and illness,” Alter wrote in the article.

Sitting at a computer all day and going to the gym for an hour of intense working out may be less healthy than having a job that keeps someone on his or her feet for most of the day, even when that person does not engage in intense exercise.

To reduce sedentary time, Alter wrote, people should try to spend 2 to 3 fewer hours per day sitting. That can be done by standing up and moving around for 1 to 3 minutes every half hour and standing or exercising while watching TV commercials, he wrote.

In an accompanying editorial, Brigid Lynch, PhD and Neville Owen, PhD note that “sedentary behavior is ubiquitous” and that “society is engineered physically and socially, to be sitting-centric.”

But before society re-engineers this behavior, it would be useful to have more information on exactly how much sitting is dangerous and to people in which specific health conditions and demographics.

“The potential for innovative approaches to reduce health risks of too much sitting, particularly for primary prevention, is considerable, but such approaches should be based on strong evidence,” Lynch and Owen wrote.