There has been some debate concerning whether or not physical inactivity should be classed as a disease.
In an article published in the British Journal of Sports Medicine, Richard Weiler Emmanuel Stamatakis said: "Given the significant associated mortality and morbidity, we propose that perhaps physical inactivity should also be considered for recognition as a disease in its own right."
However, Sue Baic, lecturer in nutrition and public health at the University of Bristol, said: "It seems to be that to some extent to some people, it's a choice, this physical inactivity, not really a disease."
She suggested that the condition could be considered as a risk factor, in the same way as smoking is.
A lack of physical activity is a recognised contributory factor to obesity, which is becoming an increasing problem in the UK.
In 2008, 24 per cent of adult men and 25 per cent of adult women were classified as obese, the latest figures from the NHS Information Centre reveal.