In my blog of 18 July 2010, I noted that a link had been found between the time spent sitting and mortality. 

A new report by Alpa Patel  from the American Cancer Foundation confirms that time spent sitting is associated with cardiovascular death. They showed that those who spend more than 6 hours a day sitting compared to those who sit for less than 3 hours a day are 37% (women) or 18% (men) during the 14 year observation period. That is double the risk for women! Even when you take regular exercise.

For those who took little exercise and sat for more than 6 hours a day, the risk was doubled for both men and women.

So exercise is good. But not sitting is even better. It won't help you lose weight, but it will help you live longer.