SYDNEY // Australian scientists have revealed research showing for the first time that the more hours a day people spend sitting down watching TV, the sooner they die. The Baker IDI Heart and Diabetes Institute in Melbourne has concluded that viewers who sat in front of the TV for at least four hours a day were 80 per cent more likely to suffer fatal cardiovascular disease than those who watched less than two hours.
"What we are starting to understand is that prolonged sitting is potentially bad for our health. This is not an attack on television itself. It is highlighting the posture people have when they are watching television," David Dunstan, the institute's head of physical activity, who led the study, said. "People who are spending high amounts of time sitting have an increased risk of early disease and other cardiovascular diseases."
Researchers believe that sustained periods of inactivity can interfere with the way the body processes sugars and fats along with other substances that can damage the heart. "When we are sitting immobile we are not getting those muscle contractions which we need to assist the body's regulatory processes," Mr Dunstan said. The Melbourne team has undertaken an exhaustive investigation into the potential harm that a simple pleasure such as an evening watching documentaries or sport can have on a nation's health. The study tracked the viewing habits of 8,800 Australians over six years, and concluded that every hour spent surfing the channels increases the chances of premature death.
Mr Dunstan said the findings were independent of traditional risk factors, including smoking and poor diet and there was a warning too that even regular exercise will not automatically protect those who sit perched on the sofa watching their favourite programmes for long spells. "Even when we factored in people's exercise levels, the relationship with television still remained," Mr Dunstan explained.
The report has been published in the American Heart Association journal Circulation and has prompted a renewed debate on Australia's mighty battle with cardiovascular disease, the continent's biggest killer, and an emerging obesity epidemic. Trevor Shilton, of the National Heart Foundation of Australia, said society has become dangerously sedentary in recent times. "In just a generation we have become a population of sitters and the prospect of our office chair or couch being a health hazard is of great interest to us. Many of us are spending 16 hours a day sitting at our office chairs, sitting while driving and sitting watching the television," he said.
"We know now that there is an entirely different physiology that occurs when we spend prolonged times sitting. It has an adverse effect on our risk factors, things like obesity, hypertension and high cholesterol. These have a big impact on diabetes, heart disease and some cancers," Mr Shilton said. The average Australian watches about three hours of television every day and in Sydney, the country's most populous city, many residents are well aware that too much television could adversely effect their health.
"It makes sense that if people are more inactive they are likely to get overweight," said Anne Pearson, an accountant. "We are leading a sedentary lifestyle on one level, but then we try to make up for it in other ways. But because society is so fast, to relax we have very sedentary forms of relaxation, which is to stretch out in front of the television. There is a problem with the way we have organised society."
"Our lifestyles make us lazy and we need that extra motivation to do something to stay fit and healthy," added Andrew Malic, 22, a university student. "Watching too much television can be a trap. I have got friends who watch too much. When they are sitting in front of the television, they are probably more inclined to get something unhealthy from the pantry, sit down, eat that and, in turn, put on weight and become obese."
The experts have agreed that there are simple yet effective ways to avoid the perils of too much sitting, whether at work or at home, where the solution is a frequent dose of standing or walking. "We have tended to underestimate the real value of these regular movements throughout the day could bring to improve our health," said Mr Dunstan, who asserted that Australians needed "an awakening" in the face of major challenges to way they work, commute and relax in order to stay healthy.
"If there is one major outcome of the study is that it has got people talking about the potential dangers of sitting for long periods," he added. The National Heart Foundation of Australia believes federal authorities should issue new public health guidelines to help the population kick its slovenly habits. "We used to, as a species, get our physical activity just by going about our daily business. These days we do need to think about it more. It is altogether too easy to go through your entire day without doing any activity," Mr Shilton said.