More than 3000 people a year in Scotland are dying from diseases brought on by lack of exercise. To be exact: 3,185 people. Of these, 80% are individuals who fall into the "very low" category for physical activity, meaning that they are doing less than 30 minutes a week of moderate exercise.

"Moderate" exertion is classed as an activity which raises the heart rate and makes you breathe faster. A brisk walk could count, if you break a sweat. Calculating exactly how much mortality results from physical inactivity is a complicated epidemiological equation.

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The equation used to calculate the burden of mortality or disease from physical inactivity. PAF stands for the proportion of.