During this book, I refer to bodyweight training also by using the term calisthenics. There is a bit of confusion and a vagueness when it comes to this word, since people use it in different ways. Following is my personal description of it and the one I’ll be using in the rest of the book. Let’s start with the origin of calisthenics. Calisthenics comes from the ancient Greek words kalos and sthenos. Kalos means beauty, which refers to the pleasure given by the sight of a very aesthetic human body. Sthenos means mental strength as in courage, braveness and determination. As a Greek person, and because I like the origin of this word, I use Calisthenics as a synonym for bodyweight exercise. For me, both words relate to the art of using your own bodyweight to develop your physical fitness and physique. I believe that proper calisthenics training should make you stronger and improve your physique, but also promote general health.