IN A world-first study, Melbourne workers are being forced out of their chairs to see if standing more throughout the day improves their health.
The trial involving 320 public servants comes after Australian research found people who sat for 11 hours or more a day were 40 per cent more likely to die within three years compared to people who sat for less than four hours a day.
People who sat for eight to 11 hours a day had a 15 per cent increased risk of dying within three years, the University of Sydney study found. The research, published in the Archives of Internal Medicine, tracked more than 222,000 people above the age of 45 in New South Wales over a three year period.
Disturbingly, the increased risk was not offset by other physical activity during leisure time, meaning those who sat 11 hours a day had the same increased risk of death regardless of whether they jogged for one hour each day or not.
David Dunstan, head of physical activity research at the Baker IDI Heart and Diabetes Institute, said the study was one of many pointing to links between long periods of sitting and serious illness, including heart disease, diabetes and cancer.
While scientists are still studying the potential causes, he said the loss of muscle contraction while sitting was likely to blame because it slowed the body's ability to clear glucose and fat from blood.
In good news, though, he said studies showed that breaking up sitting time every 20 minutes with two minutes of light to moderate movement improved glucose metabolism. Standing had also been shown to stimulate the body's metabolism.
To further examine this, Associate Professor Dunstan is recruiting 320 Commonwealth Department of Human Services workers to split them into two groups. One group will be given height adjustable desks so they can sit and stand while they work. They will also be coached to move more and wear accelerometers - a device which records the time, duration and intensity of activity.
The other group will continue working the way they are. All of the workers will have their health assessed before and after the trial, including blood pressure exams and blood tests to look at how their bodies are processing glucose and fats.
''We want to know if you can change people and if you can change people, do you get better health and productivity outcomes?'' said Associate Professor Dunstan, who spends most of his day standing at an adjustable desk.
With research showing most Australian desk workers spend three-quarters of their day seated, Associate Professor Dunstan said it was time for people to start moving more throughout the day, rather than just aiming for the recommended 30 minutes of physical activity daily.