Breatheology is not just about breathing, but about every aspect of the body and of the environment that can be affected by, or can affect, your breath. In that sense, the scope of the book is HUGE, and it is a real credit to Stig that he has been able to bring so much information together coherently. There are smoothie recipes, stretches, visualizations, stories, philosophy and lots and lots of science, all presented nice and clearly, divided into a series of chapters about breathing such as "yogic breathing", "restless breathing" and so on. The tone of the book is spot-on, just hitting the right balance between a first-person chat and an informal lesson.
Be warned if you are not into Yoga, you may be a little put off by some of the references to chakras etc. but they are nicely evened out with scientific data and the first-hand experiences also included, and most of the references to yoga are contained within one chapter.
All in all, I would recommend this book to almost anyone. There is something here for all walks of life, from athletes to stressed people, and people who are just interested in something like breathing, that is so basic and fundamental to life. The feeling you have when you finish this book is wonder because breathing is something we take so much for granted that actually focusing on it for a while is a truly magical experience. I know a decent amount of physiology about breathing, but this book has really changed my perspective a lot. Highly recommended!