Jason Crandell recently spoke about yin yoga on a Yogaland Podcast where he was interviewed by Andrea Ferretti [See episode 147.) Several people have approached me to comment on his talk. The talk lasted about one hour, and Jason made many strong assertions, each of which I would love to take 20~30 minutes to go over in detail, but – alas, I do not have that much time. A book or two could be written (and have!) on the full breadth of this topic, but I will pick just a couple of his key points to discuss.
Early in the talk both Jason and Andrea admit that in all their podcasts, they never had a yin yoga teacher on to discuss the principles and scientific basis of the practice. This was unfortunate, because there were several mistaken characterizations of yin yoga made quite dogmatically. At the beginning they both allowed that for some people, in some cases, yin yoga could be good. Jason went on to characterize who these people might be: basically, people who are very tight because they are very strong. Everybody else, he said, should not do the practice. He admitted to not knowing anything about the energetic effects of the practices and admitted that it could be good preparation for meditation or as a meditation practice, but went on to talk about why it was not a recommended practice for the vast majority of people.
Obviously, I disagree with his assessments. While there were dozens of statements he made that I could spend time debating, I will pick out the top 5:
- Yin yoga is extreme! It comes from a Chinese martial arts master, Paulie Zink, and is meant to develop a high degree of flexibility in order to build a performance art (Monkey Kung-fu). Good for the Cirque de Soleil, but not for normal people.
This is misleading. Paul Grilley, not Paulie Zink, developed yin yoga as a style of yoga. I can forgive Jason for this misunderstanding as many people have made the same mistake. Paulie Zink teaches a practice derived from his martial arts background. He has called this many things over the years: Taoist Yoga, Yin and Yang Yoga, and finally (years after Paul Grilley made yin yoga well known) Yin Yoga. However, what Paulie now calls Yin Yoga is not the practice developed by Paul Grilley and Sarah Powers. Paul did study with Paulie for less than one year back in the 1980’s, but Paul never did Paulie’s martial arts practice. Eventually, Paul developed a separate yoga class focussed entirely on long-held, passive stresses complete with opening meditation and closing shavasana, counter poses, and explanations of the postures. Paulie’s offerings were never like this and still are not like this. To differentiate his offering from Paulie’s Taoist Yoga, Paul chose to use the name “yin yoga” to make sure people wouldn’t be expecting Paulie’s Taoist Yoga. Once yin yoga became more popular, Paulie adopted the same name, but he never changed his teaching: it is still Taoist yoga derived from his martial arts training. And it is fabulous, but it is not yin yoga “Grilley style”—never was and probably never will be.
Paul Grilley extracted the passive elements from Paulie’s martial arts training, added a Traditional Chinese Medicine (TCM) basis for the energetic effects (thanks to his training with Dr. Hiroshi Motoyama), modern anatomical understanding (thanks to his studies with Dr. Gerry Parker and his own research), and placed it into a solid yogic tradition. In this form yin yoga “PG”, is far from the teachings of Paulie Zink, which is quite extreme due to its yang components. The resulting yin yoga practice most commonly taught (in the PG or Grilley style) is not extreme and never was. It is yin! Yin is mellow. Yang is extreme. In a yin yoga (PG) class, the intentions are not to go to ultimate ranges of motion, to hold beyond a reasonable amount of time, to experience pain, or any other extremism. A good yin yoga teacher would never encourage extreme attitudes or expectations. Beginners can do yin yoga and it may be better for beginners to start with a yin yoga practice than an active-yang or vinyasa practice (see my article “Can beginners do yin yoga?”)
There are only ~25 postures used by most yin yoga teachers, if even that. I use about 15. This is not an extreme number! Think of the hundreds of postures in the yang world of yoga. In yin yoga, there are no “foot behind the head” poses, or “drop back to wheel” or 108 sun salutations. The poses are seated, simply but challenging to a degree. The edge is not to be passed, but played. If pain arises, it is time to come out. Thus, I disagree with Jason and his assertion that “don’t kid yourself, yin yoga is extreme.” Sorry, it is not, at least not in the way teachers following Paul’s example teach it.
- I quote Jason “There is no rational world in which anyone, under any condition, should be randomly trying to stretch ligaments! … It is just literally the most unscientific, most unsound, mal-informed idea that we could talk about.” In many places he makes the same claim and cites the statistics that muscles can stretch 200% but ligaments only 10%. Beyond 10% they are damaged with severe consequences.
This is a common myth that pervades yoga. I don’t know where it came from! The idea that ligaments must not be stretched and can only stretch 10% before being damaged is patently false. However, Jason makes these (and many other) claims with conviction and authority but without citing any evidence or sources for these dogmatic assertions. Let me cite just a couple examples of where he is wrong.
THE LIGAMENTUM FLAVUM
Located behind the spinal cord is the very elastic ligamentum flavum, which is composed of 80% elastin fibers and 20% collagen fibers. The preponderance of elastin gives this ligament a distinct yellow color: indeed, its name literally means “the yellow ligament.” It spans a short distance, from the bottom of the anterior lamina of one vertebra arch to its lower neighbor’s top, posterior lamina, but while short, it is very strong. They serve to reinforce the posterior wall of the vertebral canal through which the spinal cord runs. Due to its elasticity, the ligamentum flavum shrinks during extension, so it doesn’t become bunched up and press into the spinal cord during backbends.
Due to its highly elastic nature, the ligamentum flavum can assist the spine in recovering from flexion by springing back to a neutral position. We don’t always use our muscles to change positions. Also noteworthy is the fact that in full flexion, this ligament may elongate by 50% of its resting length—so we see that not all ligaments resist being stretched! However, structural failure can occur if it is stretched to 70–80% —even stretchy ligaments have their limits. The ligamentum flavum is always under some tension, which helps it to retract (grow smaller) when we do backbends. If it was forcefully buckled, it could fold inward and press into the spinal cord. [Extracted from Your Spine, Your Yoga, page 132.]
THE INTERTRANSVERSE LIGAMENT
Connecting the tips of the transverse processes are the intertransverse ligaments. In the lumbar segment, this ligament is thin, almost membranous. In the thoracic segment, the ligaments are strong cords blended into the neighboring muscles. They can lengthen by up to 20% during lateral (side) flexions. [Extracted from Your Spine, Your Yoga, page 133.]
I could go and cite the nuchal ligament in the neck (the anti-gravity ligament that saves our muscles from doing a lot of work lifting up our head), the interspinous ligament and many others. Indeed, all ligaments and tendons stretch to some degree. This is good! Even the extremely stiff iliotibial band (IT band) is slightly elastic and is designed to stretch a wee bit. It is an important contributor to saving energy during running, much like the Achilles tendon and hamstring tendons are designed to stretch. (See “The capacity of the human iliotibial band to store elastic energy during running” by CM Eng, et al in Journal of Biomechanics 2015 Sep 18;48(12):3341-8. doi: 10.1016/j.jbiomech.2015.06.017. Epub 2015 Jun 27.)
To say that ligaments should not stretch is just plain wrong. They do, they should, and they must! Every time you do a forward fold, once your torso has past 45°, your back muscles (specifically the erector spinae) have completely turned off and we rely upon the ligaments and fascia of the back to control descent and to initiate returning to vertical (see Your Spine, Your Yoga, page 149). I am sure that in every class he teaches Jason has student do at least one forward fold, and when they do, they are stretching their ligaments, and far beyond 10%, without damage.
Strong and confidently asserting a fact does not make it true.
- Jason makes two other assertions relating to ligaments. The first is his claim that “ligaments run from bone to bone and serve to limit extreme ranges of motion of a joint.”
Prior to the discoveries by Jaap Vander Wal, this was the way ligaments were described in all the textbooks, so I can’t blame Jason for his viewpoint. However, Jaap’s work was pivotal in rewriting this understanding. Ligaments are in series in with muscles, not in parallel and do not serve to limit extremes of movement. (See https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3091473/.) This was presented at the 2nd International Congress of Fascia in 2009 and reported on at the time by many people, including Tom Myers (see www.embryo.nl/upload/documents/artikelen-fascie/Dynamic%20Ligaments%20The%20Revolutionary%20Re-vision%20of%20Jaap%20van%20der%20Wal%202011%20EN%20article.pdf).
The fact that ligaments are in series with muscles means that every time you stretch a muscle you can’t help but stretch a ligament! The idea that you can avoid this by slightly contracting a muscle is false. Imagine two elastic bands looped together in series. Imagine that one is very stretchy, but the second one is stiff: the first represents your muscles and the second your ligament. Now imagine stretching them: the stretchy one easily elongates, but so too does the stiff one! Just not as much. You cannot avoid stretching ligaments when you stretch muscles. Thus tightening the muscles, as Jason suggests, actually increases the stress on the ligament, which is what he wanted to avoid.
- Jason’s other assertion relating to ligaments is that they should not be stretched. Here Jason is conflating “stress” with “stretch”. They are not the same things. Many yoga teachers make the same mistake.
All tissues need some stress to regain and maintain optimal health, and our ligaments are no different. Stress is not stretch, however! When we stress our tissues, a stretch may result but it may not. We do not have to stretch tissues in order to stress them. While I have discussed above that stretching ligaments is not bad per se, what we are really trying to do in yin yoga is apply a stress to our connective tissues, not to stretch them. This is an important distinction.
There are good stresses (called eustress) and bad stresses (called distress). Our body needs stress to avoid becoming fragile. (See my article “Are yoga teachers making us fragile?”.) Yes, it is certainly possible to do too much and cause damage. That is true of any form of yoga or exercise, not just yin yoga. However, to claim that we must not stress our ligaments is to invite atrophy to the tissue.
Here is a quotation from Professor Laurence Dahners: “A common clinical finding is that unloaded ligaments not only atrophy, but also undergo contracture.” This is due, in part, to “an absence of stress generated electrical potentials (SGEP) increases contracture.” Or, in other words, ligaments need stress! (See “On Changes in Length of Dense Collagenous Tissues: Growth and Contracture” at his home page.)
It is only through stresses that tissues are stimulated to regenerate. How much stress can they take? A lot more than we will ever generate in a static yin yoga posture! (See Your Spine, Your Yoga, page 136 for the spinal ligaments and Your Body, Your Yoga, page 182 for the knee’s.) Dangerous levels of stress do not come from passive positions but from dynamic movements that create transient peak stresses that are higher than the tissues tolerance levels. This does not happen in yin yoga.
- Jason mentions long held static stresses make the tissues weaker and thus more likely to be damaged by sports.
I agree! I often recommend athletes avoid any forms of stretching before their sports (do warm up, however!) for this very reason. Do not do yoga (yin or yang!) before sports because the creep that occurs during the practice will remain for some time afterwards and this will affect your strength, springiness and reaction times. (See my article on Creep and Counterposes.) However, this does not mean never do these stresses! Do them after your sport.
This is how training works: we stress and then rest our tissues. We know this works for muscles, but it works for all our other tissues too! Even our immune system needs stress, from time to time, to remain optimally healthy. Yes, don’t do yin yoga before sports. Don’t do yang yoga before sports. Don’t do a full a bodybuilding workout before sports either! Don’t do sports with tired, stressed tissues. But this does not mean that these other practices are unhealthy. There is a time and place for each.
Final Thoughts: As I mentioned at the beginning there are many statements that Jason made that I take issue with but don’t have time to delve into (such as his perfunctory dismissal of the effects of yin yoga on fascia or his claim that yin yoga has no backbending—what about Sphinx, Seal and Saddle poses?) Jason and Andrea admit to not knowing everything. No one does. I certainly don’t either. And I would fully agree that despite any scientific reasoning or evidence to the contrary, if a student doesn’t feel safe doing yin yoga or feels it has harmed her, she shouldn’t do it! Conversely, if after years of doing this practice a student has seen the benefits and wants to continue, she should feel free to keep yinning, despite whatever science says.
Andrea also said at the beginning that she has never had a yin yoga teacher on her podcast. It would be very interesting if she did invite one to explain the science behind yin yoga and to balance the comments Jason made. Maybe one day she will!