I could try that.
It's such a complex issue. There are stages of change theory and what makes people want to take up physical activity. Where they are in the cycle will depend on how you approach that person to engage them in physical activity.
Now, this is the area of health psychology. We have a number of excellent health psychologists in Canada right now being funded by CIHR and the Heart and Stroke Foundation of Canada, trying to get at these exact issues. We don't know how to engage people in physical activity and get them to maintain it. We just don't know.