Extended sitting increases early death risk

Wednesday, February 29, 2012
Quit the sit at work
Consider a 'stand-up desk' at work
Office workers beware: sitting down for extended periods greatly increases the risk of premature death, a new study has revealed.

For many it has become the norm to be sitting for many hours of the day, on the way to work, at work, watching television or at the computer — and even those doing the recommended minimum 30 minutes of exercise per day, are not moving enough.

Research by David Dunstan Associate Professor and Laboratory Head of Physical Activity at Baker IDI Heart & Diabetes Institute Melbourne, published online in Diabetes Care — a publication of the American Diabetes Association, recommends that the hazards of sitting are now "quite compelling". Even when people exercise regularly, the study revealed, watching large amounts of television is independently associated with an increased risk of premature death.

The study followed previous research by Prof Dunstan, published in 2010 in the Journal of the American Heart Association, in which after tracking the lifestyle habits of 8,800 adults, researchers found that each hour spent sitting was associated with an 11 percent increased risk of death from all causes and a 9 percent increased risk of cancer death.

These findings provoked Prof Dunstan to question, "How ridiculous is it that people now sit longer than they sleep and what, if anything, can be done about sitting for long periods?"

Inactivity or sitting down for prolonged periods without a break can slow the body’s processing of fats, glucose and other substances as well as metabolism, which can lead to a number of health problems including atherosclerosis, carotid intima-media thickening (thickening of the arteries) and coronary artery calcium, all of which increase the risk of heart disease.

Prof Dunstan is also concerned that for most people, and the media, inactivity is associated with obesity, and that although obesity is reaching crisis proportions in Australia, the death toll for inactivity (13,491 a year) is far greater than deaths linked to excess weight (9,525).

Prof Dunstan wrote in The Conversation, an Australian university and research information online site, that his research set out to identify what frequency, and at what activity intensity, a person would need to break up sitting time in order to counteract its negative consequences.

By examining each participants' blood glucose levels and spikes after consuming a high calorie meal, it was found that insulin sensitivity and blood sugar levels improved as much as 30 percent if the participant took short breaks from sitting every 20 to 30 minutes.

"This is the first time that we've been able to demonstrate that breaking up sitting time enables our bodies to better manage blood glucose and insulin levels", says Prof Dunstan.

Raising the question at what intensity should each break from sitting be in-order to get such results, Prof Dunstan found that the benefit of walking at a light intensity pace was almost identical to walking at a moderate intensity pace, — suggesting that the simple act of standing up and moving was itself, beneficial.

Prof Dunstan said he would like to see the Australian occupational health and safety (OHS) guidelines changed to encourage workers to take frequent breaks that involve some kind of physical movement, as the current recommendation is that employees take a break from their computer screen every 30 minutes or so just to reduce eye strain.

But what can be done for workplaces, where employees are mostly desk or driving based where they are sitting for long periods of time? Dr Catriona Bonfiglioli from the University of Technology, Sydney suggested in an article, again in The Conversation that reasonable working hours would be a start, followed by attractive staircases, handy showers, secure bike racks, group activities, subsidised lunchtime activities catering to varying levels of ability and standing workstations.

Such progressive organisations that endeavour to support employees to 'quit the sit', would lead the way will to attract the best talent and set themselves apart from their competitors, Bonfiglioli recommends.

Take a look at 10 ways to increase your activity in the workplace

GettyWhy are we so fascinated by penis size, and is it the same for women? GettySleep-tracking apps can hurt your slumber, experts caution Getty imagesForget calories – are chemicals in our environment making us fat? Getty imagesAdditives that enhance texture in processed food could be blamed for making us fat