The three major factors that influence our health and longevity are genetics, the environment and behaviour. Because we have very little control over genetic factors, it is critical that we focus on the environmental and behavioural factors we can control to improve health. Whereas great strides have been made in reducing the environmental factors influencing disease, such as through vaccinations, hygiene and safety regulations, little has been done to target behavioural factors such as physical inactivity. It is tragic that so little has been done to address the one major factor affecting our health and longevity that is almost entirely under our control. At this point in time, I believe physical inactivity has become the greatest public health problem of our time and finding a way to get patients more active is absolutely critical to improving health and longevity in the 21st century.