This is an oldie, but a goody. The first edition came out in 1979, but as its intent is to provide an overview of the anatomy and physiology of breath for yoga practitioners, the fact that it doesn’t access the bleeding edge of respiratory science isn’t all that detrimental.
This short book consists of four chapters. Two chapters are by the famous yogi Swami Rama, and the other two are written by medical doctors. The first chapter is an introduction to breath from the yogic perspective. It both explains why it’s so important to understand and work with breath and introduces the mythic physiology (prana, nadi, chakra, etc.) that has historically been used to explain pranayama (breath exercises.)
The second chapter is written by Dr. Alan Hymes and it explains the mechanics of respiration. While Chapter 2 focuses on the anatomy of breathing, it begins with an explanation of cellular respiration to introduce the role of breath in powering muscles. There is a fine explanation of the operation of the diaphragm and the intercostal muscles in breathing.
Chapter 3 is written by Dr. Rudolph Ballentine, and it delves into the role of the nose and nasal cavities in respiration. Breathing through the nose is emphasized in both yoga and many other systems of breath training (e.g. the Buteyko and Wim Hof methods.) This is because the nasal cavities perform many useful functions such as moisturizing and warming air, capturing pollutants, and extract heating and moisture from exhaled breath. Besides exploring nasal anatomy and physiology, Dr. Ballentine describes jala neti shatkarma (nasal cleansing with salt water) and nadi shoudhana (alternate nostril breathing.)
The final chapter, written by Swami Rama, mostly describes various techniques of pranayama (breathing exercises) and related practices bandhas and mudras (locks and seals in which bodily parts are contracted or constricted.) However, the chapter begins with a mix of physiology and mythic physiology. That is, it explains some topics not addressed earlier–such as the interaction between the nervous and the cardiovascular systems as well as chakra.
My standing complaint about books that weave together science and pseudo-science is mitigated a bit herein. My problem with putting these ideas together is that it can be difficult for the reader to determine what concepts reflect reality and which offer models to help one visualize energy. However, except for the last chapter, this book does a good job of keeping these ideas separate. The chapters by the medical doctors present the science with minimal intrusion of unscientific concepts. Swami Rama does present science and mythology together, but not so much scrambled together in a confusing mish-mash.
Chapters 2 through 4 use a number of graphics to help present the material. In the middle chapters these largely consist of line drawings to convey the relevant anatomical features or physical actions. The last chapter adds photographs to demonstrate relevant postures. There is a page of recommended readings, but it’s more of an advertisement for other books put out by the Himalayan Institute than the recommendation of books on the science of breath.
I found this book to be educational. It packs a lot of useful information into a concise package and is readable to a layman. I’d recommend it for yoga practitioners and others who are engaged in breath work.