1. Firstly, the book focuses mainly on pranayama and asana ... obviously a narrow slice of "yoga" as practiced everyday by millions of Devotees, Babas, Sannyasis and Yogis who are a vital part of cultural and spiritual life in India. It's a tad Western-centric to use "Yoga" in the title when the focus of the book is a narrow slice of an otherwise rich and multifaceted spiritual practice.
2. Broad describes how the modern form of Western yoga is a "cleaned up" version of a centuries-old Tantric practice. The modern postures were developed in Mysore in the early 1900's as part of India's press for independence from the British. This clean, gymnastic & more regimented form of asana and pranayama practice developed by Krishnamacharya is what eventually caught on in America. In India, yoga remains a source of great National pride in both its modern scientific foundations as well as its relationship to ancient Indian culture and religion.
3. Broad provides a, ahem, broad, overview of the way in which scientists have tried to understand how and why pranayama and asana practice lead to wellness and longevity. He digs up research findings in India from as far back as the late 1800's and follows them up to the present day. This was my favorite part of the book ... his trips to the original schools in India to dig up and introduce us to the earliest research on yogis ... usually on yogis who could stay buried inside of airtight chambers. Back then, yogis were believed to have supernatural powers! Even today however, modern scientists study the physiology of hibernation among mammals and wonder if humans might be able to enter similar dormant states. Who knows how long humans can really extend the natural age limit? Maybe astronauts will practice yogic breathing someday as part of long-range space travel? Broad wonders.
He covers a great range of physiological systems such as oxygen/carbon-dioxide exchange (more oxygen stays in your brain when you breathe slowly), metabolism (yoga slows it), musculo-skeletal therapies (training new muscle groups to compensate for injured ones), symapthetic-parasympathetic nervous system (a good practice is when you cycle through poses that differentially activate these 2 branches of the autonomic nervous system), mood & cognition (yoga makes you feel great but you're kind of a space cadet afterwards), hormonal (poses to stimulate various glands), cellular (longer telomeres and healthier DNA), immunity (the vagus nerve stimulates the immune system) and many more.
As covered in the book, there are MANY ways in which pranayama and asana can be harnessed to heal the body and Broad reviews A LOT of relevant scientific evidence ... which, it turns out, often conflicts with popular hype in yoga media. There is a lot of healing power in these practices, but only if you do them in an informed and intelligent manner ... is a recurring theme throughout the book ... which is full of pointers to his favorite teachers (while reading this book, I bought, like, 4 new books on Amazon). Throughout the book, Broad seems to revere Iyengar teachers the most (Iyengar was a student of Krishnamacharya).
4. There is, a now (in)famous, chapter on injuries ... which he concedes are rare in yoga ... perhaps even less common than participation in other physical activities? ... especially among office-bound weekend warriors who push themselves too hard, too fast. He interviews several teachers who share first hand experience with injuries, and who feel that many yoga practitioners have a false sense of security when it comes to poses like, for example, shoulder stand ... where they should take more care to protect their neck and the delicate arteries that pass though the bones in the spinal column there. This being the case, Broad suggests that American yoga teachers need more rigorous training in protecting students against possible harm.
5. All of this medico-scientific study of yoga forms a very strong foundation for what Broad sees is a modern American medical system that is increasingly embracing asana & pranayama therapies. According to Kaitlin Quistgaard, editor in chief of Yoga Journal, "Yoga as medicine represents the next great yoga wave. In the next few years, we will be seeing a lot more yoga in health care settings and more yoga recommended by the medical community as new research shows that yoga is a valuable therapeutic tool for many health conditions."
So, I guess, someday, we'll pay for our yoga classes using health insurance? That would be nice. Broad suggests that the forms and certifications for such "medical" uses will need to be standardized and that yoga therapists will require far more training. OK ... it seems that the driver here will be the public/private insurance companies. Perhaps they might someday pay M.D.'s with yoga certifications? or for specific forms of yoga and breathing? I dunno ... it's their $$ and they will embrace yoga in ways they see fit. (from "The New Medicine" - Deborah Schwab, RN, NP, MSN of Blue Shield of California noted how a study of guided imagery was associated with shorter hospital stays, and lower medication costs to the tune of $2,000 per patient.)
6. There are final chapters on better sex and creativity through yoga. Skip them. Reading the physiology, brain and hormonal science - or worse - doing the specific poses, will NOT help you get laid or be a better lover. And as far as creativity and left/right brain activation goes, it's kind of a myth. "Evidence provides little support for correlating the structural differences between the sides with functional differences."
7. Which kind of brings me to the way the book really made me feel at the very end ... like I just emerged from a window-less, sterile doctor's examination room ... healthier, I suppose, but feeling sort of uninspired. I mean, is this what I'm really looking for ... to feel more relaxed and limber?
READ THIS BOOK if you want to be a yoga therapist in the United States! READ THIS BOOK if you work for a health insurance company and set up reimbursements for members to begin asana and pranayama classes ... the book is invaluable in separating the hype from the real data. READ THIS BOOK and be a more educated yoga consumer ... there is so much bewildering kooky hype out there in the U.S. yoga "free marketplace". I will definitely use a supporting blanket in shoulder stand!
But, on a purely personal, non-judgemental, for me only, personal level ... I'm practicing and studying yoga so that I can have a truly transformative, emotional, spiritual experience ... where I feel more connected to nature ... more connected to the people around me ... where my ego can be lost in a sea of love that wells up inside of me.
Yes, of course, I'll practice pranayama and asana ... to help strengthen my body. The strength and breathing will help me with meditation ... so that I can sit quietly for hours ... and still my mind. The stillness will help me listen and feel ... the earth and other people around me. The physical and breathing practices form a foundation for meditation ... which helps me become more empathetic, attentive, attuned, aware and open-minded. I care more about others ... and THAT is what feels so transformative.
I guess "Yoga" for me ... is when I seek to experience my "true self" as simply being dissolved and inter-woven in everything and everyone around me. An ego-less union with everything ... that's sort of where the magic happens for me.
I dunno if Broad would agree that THIS type of social-emotional experience is where a somewhat deeper joy and fulfillment of Yoga can be found ... not in pranayama and asana per se, as ends in themselves, but in all the wonderful things that can happen after you've been practicing ... like when you go out into the world and LISTEN and CONNECT? I dunno.
Perhaps though, he would agree that there is a ton of social, evolutionary and cognitive science to this experience too. The science of Yoga (part II) ... perhaps?