Scientists estimate you can add an extra two years to your life by simply limiting the amount you sit for in a day to no more than three hours. However the US estimates used may not be reliable to calculate personal risk. Prof David Spiegelhalter, at the University of Cambridge, said: “This is a study of populations, and does not tell you personally what the effect of getting off the sofa might be. It seems plausible that if future generations moved around a bit more, then they might live longer on average. But very few of us currently spend less than three hours sitting each day, and so this seems a very optimistic target.”
At least two-and-a-half hours of moderate-intensity aerobic activity e.g.cycling, fast walking every week, and muscle-strengthening exercises like lifting weights or digging in the garden is the advice given to adults. However in an average week the amount of sedentary activity may still be too high if for example you have an office job. Evidence is mounting on the relationship between increased sitting leadeing to poorer health. Numerous research papers link sitting and television viewing to diabetes and heart disease, and even an overall risk of death!
However a “link” is not the same as proof. The work looked at a large sample of people – almost 167,000 in total – but did not scrutinise the different lifestyles these individuals led. It is not clear how many of these people were less healthy to begin with and who, therefore, might spend more time sitting down as a result.
And the studies relied on the participants accurately recalling and reporting how much time they spent lounging around. Dr Peter Katzmarzyk and Prof I-Min Lee who carried out the review stress that their estimates are theoretical.
But given that the adults in their research spent, on average, half of their days sitting “engaged in sedentary pursuits”, the findings could provide an important public health warning. Natasha Stewart, senior cardiac nurse at the British Heart Foundation, said: “This research only suggests a causal association between sedentary behaviour and a shorter life expectancy. It also used American data so we’d need to see more research to understand what it means for the UK population.
However, it does highlight what we already know about sedentary behaviour being a risk factor for developing heart disease. And recent UK guidelines suggested we should all minimise the time we spend sitting down. We all need to be regularly active to keep our hearts healthy. So whether it’s by walking to the local shop rather than driving, or playing sport rather than watching it on TV, there are lots of ways to be more active and improve your health.”