A study published in the American Heart Association journal Circulation is being widely publicized as showing the health risks of watching TV—but it turns out the researchers found that sitting, rather than the tube, is the culprit. The implications: watch TV on the treadmill, and try to move around more at work.
The study, conducted in Australia, involved interviews with 8800 adults, all over 25 years of age, conducted between 1999 and 2006. Of those, 284 died during the study period, 87 from cardiovascular disease (CVD) and 125 from cancer. Over the course of the study, the researchers found an alarming result—for every extra hour of television watched per day, a person faced an 11 percent increase in the risk of death from all causes. That's including a nine percent increase in risk of cancer death, and an 18 percent increase in risk of death from CVD.
Pretty quickly, those risks add up. "Compared with people who watched less than two hours of television daily," said lead author David Dunstan, "those who watched more than four hours a day had a 46 percent higher risk of death from all causes and an 80 per cent increased risk for CVD-related death." Dunstan is the head of the physical activity laboratory in the division of metabolism and obesity at the Baker IDI Heart and Diabetes Institute in Victoria, Australia. But he points out that the problem isn't some magic performed by the television on the body—it's the impact of all of that, well, sitting.
"The findings suggest that any prolonged sedentary behaviour, such as sitting at a desk or in front of a computer, may pose a risk to one's health," Dunstan said. "The human body was designed to move, not sit for extended periods of time," he continued. "Even if someone has a healthy weight, sitting for long periods of time still has an unhealthy influence on their blood sugar and blood fats." That means that the problem isn't just settling in for a Top Chef marathon—it's quite possibly your job as well.
What can guys do about this, given the need for both work and entertainment in a full life? In an interview on NPR's Science Friday, Duncan spoke of his continued research on the question of precisely how much movement is required to reverse this effect. He says he is about half-way through a study that has seated participants get up and walk around for two minutes every twenty minutes. That work is not yet complete, so while we wait to see the result, he advises that a seated person get up and move around, even if that means doing a little housework, or just walking around the during the commercials. "The point is not to miss your favorite TV show," he said, "but to move around as much as possible while watching that show." Jumping jacks in the living room, anyone?