The most important chapters of the book are fifth, seventh and eighth. The chapter intensely focuses on Heidegger's fundamental ontology. At the same time running examples are given and combined with Heidegger's philosophy and reciprocally Heidegger's philosophy is combined with running descriptions in a comprehensive manner. So, the theory and practice go hand in hand. Dasein, being-there, manifests in the world in two modes, inauthentic and authentic. The inauthentic man, das Man, lives like anybody else because that is the socially proper manner to live one's life. An inauthentic person becomes authentic when she discovers herself. The sub-chapters here mainly present fundamental-ontological ways of man's being-in-the-world, which can be used to introduce the long-distance runner's realization as a running human being.