The Fitness is a widespread practice especially in Western countries and is being investigated in several respects from a scientific and health perspective as well as its role in obtaining a pleasing physical appearance. The authors also discuss fitness as a recreational hobby. Since it involves physical exercises that require an adequate preparation and not completely without risk to health, it is essential that those practitioners are made aware of both the basic principles of fitness and the potential adverse effects associated with it. This is true primarily when cardiovascular risk factors are concerned. The purpose of this book is to describe these topics in a concise way with bare suggestions for understanding the subject.