How To Critically Analyze Yoga Articles (Part One).

Via Bernie Clark
on Nov 22, 2013
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Focus by toolstop on Flickr

Frequently articles, and even books, become controversial topics of the day.

newsletter-18_examineThey are passed around in a sudden flurry of emails, sent from one yoga teacher or student to another, or appearing in Facebook posts and on other social media sites.

The controversy acquires proponents who claim to have always believed what the author of the article is stating, while other readers have a visceral antipathy to the conclusions reached. The emails and posts seek confirmation of each reader’s own bias and understanding, but through all the discussion and debate, the author’s original premises and conclusions are rarely analyzed in a dispassionate and reasoned way.

One cause for this is simply the lack of knowledge on how to critically analyze arguments presented in an article.

The intention of this article is to provide such tools, in the hopes that readers, yoga teachers and yoga students will be able to look at articles about yoga clearly and unemotionally. A side benefit would be nice as well: by understanding these tools, perhaps more yoga professionals writing articles will take greater care to ensure that their arguments are well constructed, logical and relevant.

There are several simple and useful tools that can be used to analyze an argument.

To understand how to use these tools, it is helpful to have a real life controversial article to analyze. For the purpose of this discussion, I have chosen an article that I have been asked to comment on several times. It is an article appearing in Elephant Journal on July 11, 2013, written by Michaelle Edwards entitled, “When Flexibility Becomes a Liability”.

We will look at this article in three waves: first we will investigate the relevancy of the arguments offered; second we will look at the sufficiency of the arguments; and finally we will look at validity and credibility of the premises to see if they are acceptable.


Before we begin to dissect the article, it is important to first spend a moment imagining the intention of the author in writing the article, in the interest of satya and ahimsa. Ascribe to the author a positive intention! I do believe that Michaelle Edwards is offering this article in the hopes that she will help yoga students reduce their chances of injury and harm. I share the same intention in my classes and writings.

While it is impossible for me to know exactly why she wrote this piece, by assuming it was for a positive reason I am less likely to slip into a logical fallacy of attacking her rather than her writing. Often readers will disagree with an article because of who wrote the article, rather than the validity of the arguments offered. These “ad hominem” attacks (to the person, not the argument) can be seen anytime a critic notes some irrelevant fact about the writer instead of focusing on the writing. We can reduce this tendency by imaging the writer really does have our best interest at heart, and we can thank her for her intention to help us, whether we ultimately agree with her conclusions or not.

When Flexibility Becomes a Liability

050828_0153Accompanying the article was a picture of a very flexible young woman, shown here, smiling pleasantly (as if to say, “You mean, you can’t do this?”) The article became controversial due to the disagreement many readers had to the overarching conclusion of the argument. These readers believed the article concluded that people are stretching too much and hurting themselves, even to the point of requiring hip replacements, all due to forward folding in yoga classes. The title of the article alongside this picture seems to imply “You better not do this!” But, is this a fair categorization of the article’s conclusions? [1]

Articles usually have a point to them: the basic point of the article we will call its “overarching conclusion.” This conclusion usually stems from several minor conclusions and each conclusion in turn is based upon one or more premises. Thus the general equation is: premise(s) –> conclusion(s). Frequently, conclusions can become premises for further conclusions, so a rigorous delineation between premises and conclusions is sometimes tricky. There are logical tools that can help us evaluate the validity of an article’s conclusion and the adequacy of the premises. Often, however, writers will fall afoul of logical fallacies that undermine their conclusions. There are three basic kinds of fallacies that can occur in an argument [2]:

  1. Irrelevancy (non-sequitur) – this is a test for relevancy
  2. Hasty conclusion – this is a test for sufficiency
  3. Problematic Premise – this is a test for acceptability

These are in descending order of strength, thus it is more critical for an argument to ensure that its premises are relevant than they are acceptable. There are dozens of types of logical fallacies that can bedevil an argument, but almost all of them fall into these three categories.


Let’s look at some examples of where a premise may be irrelevant to the conclusion it is supposed to support. At the end of this article is a disassembly of Edwards’ article into premises and conclusions. For ease of references, these have been numbered. Breaking an article down in this way makes is easier to see the strength or weaknesses of the author’s points and conclusions. Let’s examine her first set of premises and their conclusions:

Premises: A

  1. Being a woman means you have a higher chance of undergoing hip replacement.
  2. Women have looser ligaments than men.
  3. Excessive flexibility and weak stabilizing muscles lead to hip joint deterioration.
  4. Lumbar and hip joints must have strong tight ligaments to allow proper function of the hip joints.

Conclusions: A

  1. All women should consider practicing strengthening exercises to stabilize the hip.
  2. All women should be cautious when doing “hip openers” in yoga classes.
  3. Having more flexibility than you need compromises the longevity of your joints.

The nature of Edwards’ article does not provide one-to-one correspondences between the premises and conclusions, and few articles do, so we have to assume that each conclusion is meant to be supported by the preceding premises. But, is each premise relevant to the conclusions? For example: premise A2 is irrelevant to all the A conclusions because none of the conclusions compare men to women. The conclusions do not mention men at all, so there is no point to premise A2. Likewise, premise A1 also is irrelevant because it again compares women to men. (The premise says that women have higher chance of needing hip replacements than men. Women also have higher rates of breast cancer than men, but this is not relevant to whether a woman should have a mastectomy or not.)

Both of these premises are irrelevant to the conclusions being offered, and thus run afoul of the first test for logical fallacy. The remaining two premises, however, do seem quite relevant to the matter of women’s safety and pass this first test. We will see in our later articles whether these two premises are sufficient and acceptable and thus whether they do support the conclusions.

Paschimottanasana by kellinahandbasket on Flickr

One of the most prominent conclusions the author reaches in her writing is (D3) “Your spine does not need to be stretched.

Most yoga classes offer forward bending postures that stretch the spine, and the author is implying that all these teachers are in error, and they are risking the health of their students. This is very big claim and thus requires substantial support before it can be agreed upon.

Are the premises offered relevant to this conclusion?

If we look at the premises in (D) we find three offered; we can check now to see if they are all relevant: Premise D1 states, “Leaning over, reversing the natural lumbar curve in a quest to touch your toes does not honor the integrity of the design of our spine.” Leaning forward certainly will create a stretch along the back of the spine, so this premise does seem relevant to the conclusion. (We will see later if it is sufficient and acceptable.) Premise D2 is “Folding forward puts a lot of torque on the sacral angle.” Putting torque on the “sacral angle” (a term that is not defined) is not the same as stretching the spine, so D2 is not relevant to the conclusion offered. D3 states, “Folding forward undermines the curving forces in the spine and hip joint needed for shock absorption and hip stabilization. ”

This premise is problematic because we are not told what “undermining” means, nor what “curving forces” are, thus it is very hard to determine if premise D3 is relevant or not: we will have to suspend judgement on this premise’s relevancy until we know more clearly what the premise means. D3 also talks about the effects of forward folding on our hips, which is not relevant to the conclusion that your spine does not need to be stretched. If the premises offered have no bearing on the conclusion reached, the logical fallacy of irrelevancy has been committed. At least one, and perhaps two of the three premises offered in support of the conclusion that we do not need to stretch our spine are not relevant.

In our next article, we will continue to critically analyze Michaelle Edward’s arguments and see if her premises are sufficient to support her conclusions.

Michaelle Edwards’ Argument by Premises and Conclusions

Premises: A

  1. Being a woman means you have a higher chance of undergoing hip replacement.
  2. Women have looser ligaments than men.
  3. Excessive flexibility and weak stabilizing muscles lead to hip joint deterioration.
  4. Lumbar and hip joints must have strong tight ligaments to allow proper function of the hip joints.

Conclusions: A

  1. All women should consider practicing strengthening exercises to stabilize the hip.
  2. All women should be cautious when doing “hip openers” in yoga classes.
  3. Having more flexibility than you need compromises the longevity of your joints.

Premises: B

  1. Many people stretch their ligaments too much.
  2. These people are unaware that it can take years for damage in their joints to show up.
  3. When you sit poorly in a chair, you are flattening your sacral platform and over stretching the ligaments that attach your sacrum to the pelvis and femur.
  4. We you do a 5 minute child’s pose, you are flattening your sacral platform and over stretching the ligaments that attach your sacrum to the pelvis and femur.
  5. Long ligaments can destabilize the dynamics of our pelvis to spine and pelvis to leg attachments.

Conclusions: B

  1. Longer is not better for your ligaments.
  2. Long ligaments will lead to SI (sacral/hip) joint or groin pain.

Premises: C

  1. Many people who do yoga and stretching exercises have chronic SI joint pain.
  2. These people keep bending forward (in an attempt) to stop the pain.
  3. Forward bending poses (cause) a shortening of the front (of the body) and excessive strain and over stretching of the back extensors.
  4. Most of us are pulled forwards and are shortened from excessive time spend in chairs.

Conclusions: C

  1. Our back body is strained and over-stretched.
  2. Our back body needs to be tightened and strengthened, not stretched.

Premises: D

  1. Leaning over, reversing the natural lumbar curve in a quest to touch your toes does not honor the integrity of the design of our spine.
  2. Folding forward puts a lot of torque on the sacral angle.
  3. Folding forward undermines the curving forces in the spine and hip joint needed for shock absorption and hip stabilization.

Conclusions: D

  1. Without the lumbar curve, you end up with a flat looking posterior or butt.
  2. Without the lumbar curve, you end up with ofttimes chronic low back, knee and neck pain.
  3. Your spine does not need to be stretched.
  4. Our longitudinal spinal ligaments get over-stretched when we slouch or do yoga or fitness positions that engage the forces of spinal flexion over extension and stabilization.

Premises: E

  1. Years of tugging on ligaments can weaken the forces in the body that hold you together.
  2. As ligaments become lax, this can lead to serious postural issues, such as forward head carriage, chronic hip, back and knee pain, slowed digestion and elimination, and even a weakened immune system.

Conclusions E

  1. If you have tenderness when you walk, sharp pain when doing revolved triangle or deep warrior this is the beginning of hip destabilization and will require hip replacement.

Premises: F 

  1. Lady Gaga cancelled a tour due to hip pain that required surgery.
  2. Lady Gaga does Bikram’s yoga.
  3. Yoga did not prevent her injury.
  4. Many other famous yogis have had hips replaced.

Conclusions: F 

  1. (Poor) yoga pose biomechanics contributed to these joint destabilizations.
  2. We are not learning from these experiences.

Premises: G

  1. Toddlers bend their knees and hips, engage butt muscles and curve their spines when they fold forward.
  2. When we keep knees straight in yoga, instead flexing the spine to fold forward, we are overriding our natural design forces.
  3. Walking without bending knees is uncomfortable.
  4. If you could never bend your knees, life would suck.

Conclusions: G

  1. Keeping knees straight all the time does not contribute to the longevity of your joints.

Premises: H

  1. When you fold over and slowly straighten your legs, you will feel it in your sacral/hip joint.

Conclusion: H

  1. It does not make anatomical sense to stretch out the ligament stabilizing forces in your spine and hips.

Premise I

  1. It is not too late to strengthen your hips and butt muscles.

Conclusion I

  1. So working any yoga pose with strength and motion, instead of relaxing into a static pose, will benefit your hip/femur joint.

Premises J

  1. Strengthening your postural muscles using deep breathing while in a natural spine position can activate dormant extension and expansion forces.
  2. This will allow your bones to float.
  3. Keeping your knees bent while bending over enlists your gluteus or butt muscles which assists in stabilizing the pelvis.
  4. This contributes to functional biomechanics and strong stabilization forces.

Conclusions J

  1. Once your body works in a healthy, connected fashion, your ligaments can regain their natural length.
  2. This will protect your hip joint and sciatic nerve from wear and tear.

Premises K

  1.  The key to healthy alignment is accommodating your breathing process.
  2. Breathing dynamics provide the best tool for checking (to see) if a pose contributes towards natural alignment.

Conclusion K

  1. If you cannot take a deep breath in a pose, then the pose is activating externalizing forces in your body that overrides the body’s natural and essential core movements and infrastructures.

Premises: L

  1. Breathing deeply engages your psoas, which connects your diaphragm to the lumbar spine to the femur.
  2. Sitting in chairs shortens the psoas.
  3. Doing forward bends with straight knees shortens the psoas.
  4. The psoas is the only muscle group that is attached to the discs of the spine.
  5. In many people the inner groin is short.
  6. In many people the psoas is short and tight.
  7. A shortened psoas can affect the balance of the hip joint.

Conclusions: L

  1. Sitting in chairs can lead to bulging or herniated discs.
  2. Forward bends with knees straight can lead to bulging or herniated discs.
  3. Sitting in chairs and bending forward with knees bent can possibly lead to compression in the hip socket and deterioration of the joint.

Premises: M

  1. A pose called the core connector activates the psoas/diaphragm connection quickly.

Conclusion: M

  1. The pose called core connector  restores equilibrium in the psoas.
  2. Balancing the actions of the psoas can stop chronic back pain, stabilize the spine and create a fluid balance of the whole body.

Overarching Premise: N

  1. Yoga practitioners will often suffer from injuries.
  2. Spinal ligaments are getting stretched beyond their anatomical function when we do poses that take our spine into the C shape.
  3. The C shape of our spine is the bane of aging.
  4. The human body is made of curves and spirals.

Overarching Conclusions: N

  1. When posture is naturally aligned the human body stays flexible.
  2. Intense stretches to relieve tension of the parts are not needed.
  3. What has the most value is to remember our innate postural patterns and preserve the natural integrity of our spine and joints.


1: The article was given new life when William Broad reported on it on November 2, 2013 in a New York Times article titled Women’s Flexibility is a Liability (in Yoga). Paul Grilley posted an analysis of this article on November 6, 2013 at Teachasana.

2: See Logical Self-Defense by Johnson and Blair, page 12.


Read Part Two and Part Three.


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Editor: Bryonie Wise






About Bernie Clark

Bernie Clark is an author, yoga teacher, creator of the website and author of The Complete Guide to Yin Yoga. He has been teaching yoga and meditation since 1998 and has a degree in Science from the University of Waterloo. Combining his intense interest in yoga with a scientific approach to investigating the nature of things, his ongoing studies have taken him deeply inside mythology, comparative religions, psychology and physiology. All of these avenues of exploration have clarified his understanding of the ancient Eastern practices of yoga and meditation. Bernie’s teaching, workshops and books have helped many students broaden their understanding of health, life and the practice of yoga. His latest book, Your Body, Your Yoga goes beyond any other “anatomy for yoga” book, which focus on the muscles while ignoring the fascia, bones, the nervous system and human variations. It is "Required reading!” according to Drs Timothy McCall, Loren Fishman, Gil Hedley, Stu McGill, Robert Schleip and many others


13 Responses to “How To Critically Analyze Yoga Articles (Part One).”

  1. KarenF2 says:

    Thank you Bernie Clark!! I Love your brilliance and delivery. I have been working on my 500 hour project and finding this to be so pertinent to the growing articles that are flying by me daily on yoga. Namaste.

  2. Bernie says:

    Thanks Karen. I hope it does help you, and many others, work through all the rhetoric to find the nuggets of truth, if any, buried within.

  3. jessofwight says:

    Thank you Bernie; although I receive it critically, your writing is always a joy – here, on the YY forum, and in print.


  4. Bernie, thanks for your input and I’ll use it to make the message of my practicing good posture over good poses more clear in my upcoming articles. You make some good points concerning double blind testing versus anecdotal evidence as well as overarching premises and conclusions used by me in my article. However using language or the written word to describe the effectiveness, value, or inherent dangers in the practice of yoga poses as in my article; is always going to bring up fallacies according to logic and the scientific method. Yoga encompasses a multi-dimensional experience difficult to prove,control or quantify as many yoga teachers protesting regulation of yoga will attest.
    However your CI or creditability indexing mention gave me a great idea. How about we ask the British Royal Society or the American Association for the Advancement of Science, the gold standards of creditability to analyze individual yoga poses the way you did for every statement in my article? Every yoga pose would be evaluated individually in a double blind study by kinesiologists and orthopedists at credible recognized universities conducted by unbiased scientists, not affiliated with any yoga style or group. Each yoga pose would be to scientifically and logically tested, analyzed and then indexed according to health enhancing properties vs ones deemed to be damaging to the human body. With MRI imaging and muscle contraction sensing equipment available to scientists, there would be hard evidence about these poses that would have scientific creditability. We could call it the YPCI or yoga pose creditability index. Given how many yogis do not even want yoga teaching to be regulated, I think many would protest. Especially those invested in particular styles whose creditability and livelihood could be affected if certain yoga poses or styles were deemed to be dangerous and unproductive in the long or short term.
    Also since you appear to be an expert at using logic principles of evaluation, how about doing a critique on the article printed by the Association of Bone and Joint Surgeons stating how it is the usage of the hip joint causing hip problems not necessarily bone shape that leads to hip problems? This paper was cited in William Broad's latest article on Women's Flexibility is a Liability in the New York Times Sunday review.
    According to the research and conclusions of Reinhold Ganz, an orthopedic surgeon at the University of Berne, in Switzerland, there is hard scientific evidence that hip flexion at 90 degrees and deeper can lead to impingement of the acetabulum, labrum tears and joint dysfunction. The evidence here clearly shows that straight leg seated and standing forward bends can lead to labrum tears since we are going way past 90 degrees flexion to even 180.
    Here is the link
    I think it would be great as your next example of critiquing articles and helping us all feel safe that the article or writer is credible according to your expert opinion. Michaelle Edwards

  5. Bernie says:

    PaHello Michaelle: first, let me say that your desire to help your students is obvious through your passion, which is commendable. You asked me at the end of your comments to critique the paper “The Etiology of Osteoarthritis of the Hip” according to “my expert opinion.”

    I do not claim to be an expert in this field, and that, actually, is part of the point of my article: one does not need to be an expert in science or in yoga to analyze the logic of an argument. One does not even need to be a master logician – one only needs to apply a few simple logical principles: 1) check to see if the premises offered in support of a conclusion are relevant to that conclusion; 2) check if the premises are sufficient to establish the conclusion; and 3) if so, are the premises acceptable. So, in this vein, I did read the article you suggested I look at, but let’s first look at what you got out of this article, again broken into simple to digest statements:

    •P1: Your first premise is that the article states, “… it is the usage of the hip joint causing hip problems not necessarily bone shape that leads to hip problems.”
    •P2: Your second premise is that the authors concluded “that hip flexion at 90 degrees and deeper can lead to impingement of the acetabulum, labrum tears and joint dysfunction.”
    •C1: And based on these two premises you conclude that “The evidence here clearly shows that straight leg seated and standing forward bends can lead to labrum tears since we are going way past 90 degrees flexion to even 180.”

    Let’s look at P1: You are suggesting that the authors of this study found that hip joint usage cause hip problems. That is not what I found when I read the paper. Indeed, the authors several times mention that the cause of hip problems are pre-existing pathologies of the hip, not stresses caused by movements. They state this several times as their overarching theory. For example, in their Abstract they note, “primary osteoarthritis [OA] is … secondary to subtle developmental abnormalities and the mechanism is femoracetabular impingement [FAI] rather than excessive contact stress.” Their point is that, not only is the majority of hip OA caused by obvious developmental abnormalities, especially in youth, but almost all problems are also caused by such developmental issues. They restate this theory in their concluding discussion: “There is an increasing body of evidence that most hips that fail to OA without severe deformities of the joints do so with the mechanism of FAI based on subtle or moderate morphologic abnormalities of the joint components.” In other words, FAI is a result of hip abnormalities, not a cause of them. Once more they reiterate this when they say “the theory proposes … OA of the hip … are indeed caused by minor developmental deformities [which] cause arthritis to develop from … FAI.” [Page 2] They cite several examples where it is the shape of the bones (specifically the acetabulum when it is in retroversion) and the femur (when it has a “pistol grip” shape) that cause the problem. They actually cite several statistics showing how common bone morphology is to the occurrence of OA: “…approximately 90% of the cases of adult hip OA were associated with some developmental abnormality.” [Page3]

    The only place where they mention usage of the hip at all, is when they state, “The pincer-type FAI produces a rather slow process of degeneration and occurs more often in women between 30 and 40 years of age engaging in activities with high demand like yoga or aerobics.” The context here is, however, that these women already had an underlying developmental abnormality and “high demand” exercises tended to bring out degeneration in some of these women. Of course there are yoga styles that are “high demand,” but there are also many yoga styles that are not aerobic in nature, so it is not clear if they meant to implicate all yoga styles, nor do they imply that all women are in danger. They are talking about women who have hidden developmental abnormalities in their hips. Unfortunately, they do not define what “high demand” means. [Interestingly, however, at the end of their paper they do refer to another study these same authors did, where they do make clearer what they mean by “high demand”. In this study they said, “High velocity movements, frequently occurring during athletic exercise may play a detrimental role.” Again, not all forms of yoga practice fit this description.]

    From these quotations and others within the article, I can’t find substantiation for your first premise; the authors do not point to hip usage as the cause of hip problems, but rather the whole point of their paper is that they are caused by bone anatomy and morphology arising in youth and during development of the hip.

  6. Bernie says:

    Part Two:

    Similarly with your second premise (P2), I cannot find your quote “that hip flexion at 90 degrees and deeper can lead to impingement of the acetabulum, labrum tears and joint dysfunction.” Since this was not a direct quote from this article, it clearly is a conclusion that you have reached by reading the article. Is this a valid conclusion? The authors state that FAI is a consequence of development abnormalities; they do not state that it arises from hip flexion. They do admit that for people who have these abnormalities, which give rise to the FAI, then “the most critical motion is internal rotation of the hip in 90° flexion.” [Abstract] They also cite another study in their discussion, at the end of their article, that found 90° hip flexion with internal rotation can increase acetabular rim pathology, but again this is for people who have the pre-disposition. Note: they never mention what happens when someone goes “deeper” as you imply in your premise, and they do not talk at all about 180° hip flexion.

    The authors, both in this study and the second study they reference, point out that it is internal rotation that causes problems when FAI is present. This makes sense and is worth spending a moment on. When seen from the side view (the sagittal plane) the hips socket can be viewed like a clock. Flexion or extension of the femur does not create any impingement or compression in the acetabulum. The femur moves freely back and forth in the sagittal plane, but when we add internal rotation, now the neck of the femur pinches inward and may meet the rim of the acetabulum. Where this occurs does depend up the degree of hip flexion. If the person is standing, internal rotation would create impingement at the 3-o-clock position on the acetabulum. If the hip was flexed 90° the impingement would occur at the 12-o-clock position. If the hip was flexed fully (180°), then the impingement would be at the 9-o-clock position. The authors state, “The most frequent location for [FAI] is the anterosuperior rim area…” [Abstract] which is roughly the 1~2-o-clock position. Thus it is when the hips are flexed almost 90° and internal rotation added that FAI occurs at the weakest part of the hip socket. Flexion of the hips to any other degree is not a problem. Your premise P2 says that flexion alone is the problem, and clearly this is not what the authors are saying.

    Since I cannot find support in this article for either of your two premises, it is hard for me to see the validity of your conclusion that “The evidence here clearly shows that straight leg seated and standing forward bends can lead to labrum tears since we are going way past 90 degrees flexion to even 180.” The authors never discuss sitting or standing positions, they never discuss the difference between legs straight or bent, but they do point to the underlying cause of FAI as being development abnormalities. That is the whole point of their paper. They discussed a wide variety of hip OA causes such as “inflammatory diseases … such as rheumatoid arthritis, ankylosing spondylitis, Reiter’s syndrome or lupus … as well as … gout … osteonecrosis and fractures.” They are also very clear as to what developmental abnormalities are, beyond those causes of OA just cited: “…many cases of hip OA result from severe developmental or acquired deformities of the hip that occurred in infancy or childhood.” However, these deformities were mild in many people so no one thought that they could be the underlying cause of the hip degeneration. The point of their article is that these developmental problems are the source of OA, not flexion of the hips!

    This article does not imply that every women needs to refrain from seated or standing forward bends because they risk degeneration of their hips. It does say that some people, those with developmental abnormalities, could further exacerbate their problem if they place a “high demand” on the hip at a 90° flexion with 10° internal rotation. This does suggest that, as yoga teachers and practitioners, we need to stay alert for signals from the body that warn us of impending danger in the hip. But that should be standard operating procedure for all yoga poses and for any joint, not just the hips.

  7. Bernie says:

    Part Three:

    From my perspective, what I found interesting in this article is the emphasis on individual skeletal variations: many people have perfectly normal hips with no abnormalities, but there are also some people who have retroversion of the acetabulum or the pistol grip shape in the femoral neck, and these morphologies could lead to compression in the joint which over time and with high demand could lead to degeneration and OA. Interestingly, in their second study cited, they actually quantified how frequent these non-problematic abnormalities are (~24%) but they also note that, despite these skeletal variations, most people will never manifest any OA because of them. When OA does occur, it is excessive compression, caused by “high demand” that wears down the bones and cartilage, but it is the variation in morphology and anatomy (skeletal variations) that leads to the compression – not stretching the hamstrings or the spine. For people who have such hip developmental pathology, care should be taken not to stress the joint further by internally rotating the femur when the pelvis is near 90° flexion. That is good to know. Pure flexion of the hips, however, without internal rotation does not, based on this study, risk osteoarthritis or degeneration.

    To come back to the point of my original article: when we write about Yoga and its possible dangers (or indeed on any other topic), we owe it to our readers to have our premises supported by evidence, to make them credible. The premises stated should be relevant to our conclusions and sufficient to establish the conclusion. Your argument that flexion exercises in yoga are dangerous and should be avoided would be well served if your underlying premises were supported more directly with evidence, rather than left as simple assertions. I know that you strongly believe your argument to be true, and I admire your desire to help students prevent injuries. Constructing a well-reasoned, logical basis for your argument may better help you achieve your goal.

  8. Here is a website with hip replacement statistics. Women do get the majority of the surgeries and often need repeat surgeries too.….

    Also a Mayo clinic study shows serious dangers for people who do forward bends with osteoporosis.

    Also see the prevent yoga injury blog about forward bends….

    Yoga teachers with hip replacements, Beryl Bender, Judith Lasater, Mary Dunn, Dharma Mittra, George Purvis,
    You can critically analyze my writings but the truth be told. Yoga teachers are getting hip replacements. You may use logic to state that there is no scientific proof that yoga caused it. But yoga did not prevent it either. In my world, nobody should be getting hurt doing yoga and the fact is people are getting hurt and we are not able to see reliable scientific statistics on the numbers because yoga is not regulated and only acute injuries usually wind up at the emergency rooms. Statistics on chronic injuries are not available or reported which is why there is a serious denial in the yoga community about yoga injuries.
    I feel and my body tells me that the dangers of yoga asana are getting in positions that do not simulate how the body is designed to move. ( for instance bending over with straight knees) Here is where repetitive strain and excessive joint actions create issues in the long term.
    People talk about bone differences and how we need to move our spine. Agreed our spine actually gets moved every time we inhale or exhale but there is no need to bend the spine excessively when bending forward. Any back doctor will tell you, bend your knees. Explain to me in anatomical terms how bending over with the knees straight is beneficial for our body.
    Check out the posture gurus here.….

  9. Hi Bernie , I am very interested in hearing how doing forward bends with straight knees is beneficial for our body as I cannot seem to come up with any anatomically functional and logical reason to do it.
    Also heres a link from a comment on William Broads latest post on Elephant journal.
    YIN YOGA injury
    This is a comment that just posted on this article

    Thank you, William, for your diligent research on this often ignored subject in yoga. As a yoga teacher and practitioner, I too have experienced hip-related issues. My hips have always been quite flexible and without any knowledge of the chance of injury I spent a large amount of time in Pigeon pose (yin style) and was the envy of many of my students. Unfortunately, I now have severe Pudendal Neuralgia (mostly on the right side). For those not acquainted with this nerve, the pudendal nerve runs from the sacrum through the anal and vaginal area, the urethra, clitoris, labia (all the extremely sensitive spots!).

    This has been the most excruciating pain I have ever encountered. I am blessed to have a specialist in my area who is aware of this type of injury. I have had nerve blocks done which have helped quite a bit. I have now had a further minor surgery call "radio-frequency ablation" in which the ends of the nerve a burned. This has been very successful and has allowed me to have a life again. Causes of this include a severe fall which can lead to the nerve being "trapped", over-stretching, and inflammation.

    I now do only very gentle yoga and leave out pigeon pose, triangle, deep forward bends, and squats. I urge all women (and men) to be mindful of their bodies and research anatomical issues. William Broad's book is a great place to begin. More information and awareness needs to enter the yoga field before we see yoga related injuries begin to sky-rocket.

  10. bob says:

    How do you arrive at the conclusion that forward bends caused the arthritis in the yoga teachers you mention? If you are saying that flexing the hip greater than 90 degrees is dangerous, then the method of forward bends you are advocating (with the knees flexed) is potentially more dangerous, simply because removing the constraint of the hamstrings allows much greater flexion at the hip. When you bend over to tie your shoe, you flex the hip greater than 90 degrees. Childs pose flexes the hip far more than most people can do in Paschimottanasana.
    The teachers you mention did all types of poses. There is no evidence that it was forward bends that was the cause of their arthritis.

  11. bob says:

    You recommend bending the knees in forward bends. By your logic, the very method you are recommending is dangerous for the hip because bending the knees allows greater flexion of the hip.
    Malasana, happy baby pose, any squatting pose, running, climbing a staircase (2 steps at a time), and the method you recommend for practicing uttanasana (with knees flexed) all flex the hip joint more than when you have the knees straight. All flex the hip more than 90 degrees. Having the knees straight actually prevents flexing the hip because the hamstrings are hip extensors. So if you're worried about the danger of flexing the hip more than 90 degrees, then keeping the knees straight is a good idea.

  12. bob says:

    Good article Bernie. On pincer deformity, new longitudinal studies show it does not lead to arthritis and may have a protective effect against developing it.

  13. Bernie Clark says:

    Hi Michaelle – rather than continue to discuss your thesis that flexion causes hip problems in the comment section, I posted a new article which hopefully addresses your questions. You can find it here: