Worth a read from the Beeb, just incase you needed a little more persuasion that exercise is good for you:
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.
And with that, I should really get out for a run now…