ABSTRACT
It is dif—cult to overlook the fact that there is a worldwide obesity epidemic. Various media bombard us regularly with messages about this condition and its widespread effects. We are —rst-hand witnesses to the phenomenon, and quite possibly are also among those who are now (or will be) counted as overweight or obese. The relationship between physical activity and obesity is complex; however, the purpose of this chapter is to de—ne important terms and provide an introduction to select relevant current topics: an overview of the obesity epidemic; an introduction to the notion of creeping obesity; a review of the role of physical activity in preventing weight gain, promoting weight loss, and preventing weight regain; a discussion of the relationships between sedentary behavior and obesity, and also walking and obesity; and an introduction to the —tness-versus-fatness debate.
