Both a sedentary lifestyle and physical inactivity have specific effects on health which must be addressed separately if we want to better understand their distinct mechanisms.

Many epidemiological studies over the past few years have established that the risk of having coronary heart disease is 2 times higher in sedentary people than in active people. In addition, being physically inactive is apparently a higher risk factor for developing coronary heart disease than smoking is.

Physical inactivity and a poor diet have become major public health issues since, together, these two poor lifestyle habits are the second real cause of mortality, after smoking, in the United States. 

Defining “sedentary behaviour” or “physical inactivity” is difficult and there is no consensus on their definitions. One thing is certain – we should move more and spend less time sitting!