The evolution of the human body has undoubtedly been based on the physical needs of a hunter-gatherer lifestyle. We have evolved to become fantastically efficient at continual movement on two legs (i.e. walking), with an ability to run, sit and rest as required. However the 21st century allows for a far more sedentary lifestyle than the role a hunter-gatherer once lived. No longer do physical tasks rule our daily needs as computers, televisions and cars all allow us make money, be entertained and travel, all with our backsides remaining fixed to a chair. So is this extra sitting time problematic, now that our bodies are being used in ways they were never designed?
There is no doubt the average sitting time of Australians has increased as technology changes work and recreational habits. The Australians Bureau of Statistics stated that in 2011-2012, Australian adults spend an average of 4 hours each day performing sedentary leisure activities – like watching TV. A study published in 2009 by Medibank Australia reinforced the trend towards significant portions of an average day spent sitting. They stated that as much as 70% of an average work day is spent doing sedentary activity. Interestingly 62% of non-work days were also spent in a sedentary position for an average working Australian.
So what are the physical impacts in spending a significant time sitting? An article in The British Journal of Sports Medicine in 2012 suggested that increased sitting time reduced life expectancy. Comparing the length of life for those who watched large amounts of TV with those who didn’t watch TV produced alarming results. Those who watched on average 6 hours of TV a day were shown to live on average 4.8 years less than someone who never watched TV. This equated to 22 minutes less life expectancy for every hour of TV watched.
Further to this, a 2012 review of research into sedentary lifestyle looked at the results of studies encompassing 800,000 participants. There were some weak links that sitting increased the likelihood of back pain, but the telling findings was that those who spent the most time sitting were more than double the chance of getting diabetes, almost 2.5 times the chance of a heart attack, and 1.5 times more likely than those who sat the least of death from any cause.
So in a world where everything is seen to possibly cause cancer, are we overreacting to this information? Is sitting really what is reducing life expectancy, or is it a lifestyle that unites reduced activity? This will no doubt always be a debated subject, and likely one that never has a cut and dry answer. We are so aware now of the negative effect of each cigarette smoked but many are completely unaware of what other health risks they engage in. What is obvious is that reduced activity is likely to bring about a range of potential health issues and should help influence the decisions we make. So now when each of us are next faced with an option of being active or sedentary, hopefully this decision now becomes an easy one.
Written by Mark Fotheringham