http://news.bbc.co.uk/2/hi/health/7212698.stm
Leading a sedentary lifestyle may make us genetically old before our time, a study suggests.A study of twins found those who were physically active during their leisure time appeared biologically younger than their sedentary peers.
The researchers found key pieces of DNA called telomeres shortened more quickly in inactive people. It is thought that could signify faster cellular ageing.
An active lifestyle has been linked to lower rates of cardiovascular disease, type 2 diabetes and cancer.
However, the latest research suggests that inactivity not only makes people more vulnerable to disease, but may actually speed up the ageing process itself.