No better book on the discipline of running exists. What I appreciate about Noakes it that he presents all the scientific perspectives fairly and then presents his own view. It sounds like a simple task but most authors demonstrate clear bias, often wrenching data from other views to support their own. Such is not the case with Noakes. He presents summaries of all the best research on fitness and running, starting at the cellular level, moving up to the muscular level, including the systemic hormone/nutrition levels and finishing with training programs. The book is huge. I've read it cover to cover twice and often refer to it as I reach certain issues in training. The lessons of the book apply to all disciplines of triathlon. A huge resource if you want to get scientific about your fitness.