5 Things We Didn't Learn About the SI Joint in Yoga Teacher Training

Today I'd like to offer 5 insights about the SI joint (or sacroiliac joint) that we don't tend to learn about in yoga teacher training, but which definitely have implications for how we teach and practice yoga. Also included are multiple scientific references for each point. I invite you to read these points with an open mind and a willingness to possibly question your own biases (because I know I have had to question my own many times as I continue to study and learn about the body!)

 

 

Insight #1: The SI joint is a strong, resilient structure that is supported by thick layers of some of the strongest ligaments and muscles in the body. [Ref, Ref, Ref]


Although the SI joints are some of the strongest joints in the body, we often receive the impression from our yoga teacher trainings that they are actually quite fragile structures that are vulnerable to injury and instability from the slightest misalignments in yoga. For example, we are sometimes taught that if we hold our pelvis "square" when we twist in poses like twisting triangle (parivrtta trikonasana), we can "tweak" our SI joints by pulling them out of alignment, and we should therefore instead always be mindful to let our pelvis turn slightly in the direction we are twisting in these poses. Another example is that we are often instructed in backbends like bridge pose (setu bandha sarvangasana) and locust pose (shalabhasana) to relax our glutes (or to at least soften them somewhat) because if we contract them too hard, this could injure our SI joints.

One reason we tend to believe that our SI joints are vulnerable to damage in yoga is that we generally learn about SI joint anatomy by looking at a skeleton model or a drawing like this one here:

 
 

When we see the bones by themselves like this, we can certainly get the impression that the sacrum can "slide around" relative to the pelvis easily, resulting in an SI joint that can be pulled "out of place" or "strained" due to small misalignments in yoga poses.

However, what we rarely see after learning about the bony anatomy of the SI joint's structure is an image like this, which depicts all of the extremely resilient, tough ligaments that surround and support the SI joints from all sides, holding them firmly in place:

The ligaments that support the SI joint include the anterior sacroiliac ligament, interosseus sacroiliac ligament, sacrotuberous ligament, posterior sacroiliac ligament, and sacrospinous ligament.

The ligaments that support the SI joint include the anterior sacroiliac ligament, interosseus sacroiliac ligament, sacrotuberous ligament, posterior sacroiliac ligament, and sacrospinous ligament.

 

A rarely-cited fact is that the ligaments of the SI joint include some of the strongest ligaments in the human body! [Ref]

If after seeing an image of the SI joint's ligamentous support, we were then shown an image like this one below, which depicts all of the thick musculature and fascia on top of all of those ligaments on top of the SI joints (including the powerful gluteus maximus, the largest muscle in the human body), we might have reason to be more confident and less fearful about this naturally strong, sturdy area of our body:

 
 

 

While our SI joint can certainly be injured and we can absolutely experience pain there (more on this in #4), it would take much more force to injure a healthy SI joint than the relatively low loads involved in a yoga practice.

 

Insight # 2: The SI joints are inherently stable by design, not inherently vulnerable. [RefRef, Ref]

The SI joints serve to transfer the load of the upper body to the lower body, as well as to distribute forces moving up the body from below. Therefore, stability is built into their very design so that these forces can be transferred efficiently through the pelvis.

In fact, the SI joints are so inherently stable that there is only the tiniest amount of movement available at these joints. While some sources state that the amount of motion available at the SI joint is a barely-perceptible 2-4 millimeters, other sources actually state that there is in fact no movement available at these joints at all.

 

Insight #3: Even if the SI joints could "slip out of place" easily, we don't have a reliable way to assess this in someone's body. [Ref, RefRef, Ref, Ref]

SI joint movement is so minute and difficult to identify with either manual palpation or radiographic imaging that none of the tests traditionally done to assess the SI joint have been shown to be reliable. Without an accurate method for testing the position and movement of an SI joint, how can we definitively know that someone's SI joint is "out of place", "misaligned", or "unstable" in the first place?

 

Insight #4: SI joint pain is certainly a common experience among yogis and non-yogis alike, but SI joint pain does not necessarily mean that there is an SI joint injury. [Ref]

His left hand would actually be a bit lower if this were truly SI joint pain. (I couldn't find a photo that showed the right spot - they all seem to feature general low back pain instead!)

His left hand would actually be a bit lower if this were truly SI joint pain. (I couldn't find a photo that showed the right spot - they all seem to feature general low back pain instead!)

Thankfully, insights from modern pain science are beginning to become more widely known in the yoga world, but if this topic is new to you, consider taking a look at the introduction to pain science article that I wrote for Yoga International a couple of years ago. It turns out that despite what we have traditionally been taught, pain and tissue damage often do not correlate on a 1:1 basis - especially when pain is experienced in a more persistent or chronic way. Pain is actually a much more complex, multi-factorial phenomenon than simply "I have tissue damage and therefore that is what is creating my pain."

As an example, if someone has SI joint pain and they have experienced a recent blunt force trauma to their pelvis region (think from a car accident or a major fall of some sort), then their pain is very likely due to an actual SI joint injury. Once this injury has healed, this pain should subside. In fact, my husband and I suspect that his SI joint may have been injured many years ago in yoga by a strong adjustment he received. His yoga teacher forcefully pulled both of his legs behind his head in a pose called dwipada sirsasana and he felt a searing pain at his left SI joint in that moment. Thankfully the injury healed, but this type of forceful, deep adjustment seems like it was enough to cause injury to his SI joint (or at least a strong protective output of pain in the area).

But in contrast to those examples of short-term pain associated with acute injury, when someone's SI joint pain is more long-term or chronic in nature (chronic pain is sometimes defined as pain lasting longer than 3 months), it's less likely that this pain is connected to a specific injury or damage to the area, and more likely that the person's nervous system is instead sensitive around that spot. Nervous system sensitivity and an output of pain can be the result of many different factors aside from actual tissue damage. Other influences include emotions, past experiences, stress levels, beliefs - and particularly beliefs about one's body. In fact, the more that someone believes that their SI joints are fragile and vulnerable, the more likely their nervous system is to perceive threat in that area and to output pain there. And conversely, the more someone learns that their SI joints are strong, inherently stable structures well-supported by some of the most durable ligaments and muscles of the body, the less likely their nervous system will be to perceive threat and output pain in this area. [Ref, Ref]

 

Insight #5: Warnings about protecting the SI joint in yoga are often unnecessary.

As we have seen, the SI joints are held stable by a ligamentous and musculature support structure that is strong and resilient - and the joints themselves have only a tiny amount of movement available (if any) in the first place. With this in mind, whether or not we hold our pelvis square when we twist in yoga is probably not a likely mechanism for SI joint injury either way, given the relatively low loads involved in the pose. And whether or not we squeeze our glutes in backbends in yoga is also unlikely to be a mechanism for SI joint injury; in fact, contrary to the common cautions in yoga, contracting our glutes in backbends has actually been shown to have a positive stabilizing effect on the SI joints. [Ref, Ref]

Additionally, it's common these days to hear warnings about "overstretching" the ligaments of the SI joints in yoga poses, leading to SI joint instability and pain. (I myself used to offer such cautions too - the idea just seems to make sense!) We are learning, however, that this is not actually how ligaments respond to stretching. During a stretch, a ligament lengthens temporarily, but then it returns to its resting length afterward (sometimes after a short recovery period.) Despite popular warnings, passive stretching has not been shown to lengthen and destabilize ligaments and joints. I have personally changed my perspective on this issue due to insights from newer research and teachings from my yoga biomechanics mentor Jules Mitchell.

(For more reading on the fascinating topic of stretching, ligaments, and joint instability with lots of research references cited, I encourage you to read this recent blog post by Greg Lehman, a researcher and clinician whose work I have followed and admired for quite some time now. But fair warning: this post is long and is really territory for the more serious body geeks among us. You can always jump right to "Questionable Assertion #3", which specifically addresses these topics and might offer some new, interesting information for you to ponder.)

 

IN CONCLUSION...

In summary, SI joint pain is common among yogis and non-yogis alike and there are many factors that can contribute to it, including physical, psychological, and social ones. How we align our body in yoga is probably not a mechanism for SI joint injury, though (strong, forceful adjustments by yoga teachers excepted!) Rather than worrying too much about alignment for SI joint protection, a more effective means to injury-prevention is to simply strengthen and condition the muscles and connective tissue that support the SI joint, so that their capacity to handle load increases.

Thank you for reading these 5 points with an open mind, and I hope to see you on the mat virtually or in person in the near future!

[Microblog] Anatomy Geek Stretching Thought of the Day

ANATOMY GEEK THOUGHT OF THE DAY: We often think of a muscle contraction happening only when a muscle *shortens*. But muscles work just as often as they lengthen - picture your hamstrings and the way they lengthen while they work to control your swan dive into uttanasana (standing forward fold) in yoga. When a muscle works as it lengthens, this is called an *eccentric contraction*, and we move this way all the time in our normal human movements.

One of the core rules we tend to learn in our yoga teacher trainings is that after we've "worked" a muscle or muscle group, we should stretch that muscle group to "balance it out". But because muscles can and do actually contract through all of their ranges (short, long, somewhere in between, etc.), is it skillful to consider the opposite of a muscle contraction a *stretch*? Do these two "balance" each other out? If it turned out that they were not necessarily opposing actions, would this change the way you sequence your yoga classes at all?

Enjoy pondering this one, and feel free to let me know how it goes!

Three Alternatives to Pigeon Pose & A Brief Discussion About Stretching

I know I might be in the minority amongst yoga teachers, but even though yoga students tend to looove their pigeon pose, I have consciously chosen to forgo this pose in my classes for the past several years now. While I do teach variations of pigeon pose like reclined pigeon and standing pigeon chair, I don't generally teach the traditional version of this pose in which you lie in a passive, unsupported forward fold over the front leg.

 

WHY I SKIP PIGEON POSE - REASON #1

I have two main reasons for skipping pigeon pose in my classes. The first is that it doesn't offer much in the way of positive change for the tissues of the body. We generally tend to think of pigeon pose as a stretch designed to increase the flexibility of the hips. But we've actually learned quite a bit more from scientific research in recent years about how stretching works (although there is still a ton that we don't know!), and thanks to my brilliant mentor Jules Mitchell, much of this new information is making its way to the yoga community.

One of the biggest realizations that I've learned about stretching is that flexibility is a much more complex topic than we've generally learned from our yoga teacher trainings, workshops, books, and other studies. The prevailing approach to flexibility in most yoga classes (and in much of the health/fitness world in general) is that if someone lacks range of motion in a joint, the solution is to stretch the muscles and fascia that cross the joint to lengthen them out. Then we get longer tissues and voila! - we can stretch further in that direction. By this reasoning, the solution to the ubiquitous "tight hips" that many people claim to have is to simply stretch one's hips out in pigeon pose for a long time at the end of every yoga class - a practice that we yogis are quite familiar with!

But the assumption that in order to solve all inflexibility issues, tissues simply need to be stretched out does not take into account the many other likely factors that could be causing the inflexibility - factors that passive stretching does not actually address. It reminds me of pain science and how easy it is to attribute pain simply to structural factors like tissue damage, poor alignment, or dysfunctional movement patterns, when the bigger picture of pain is truly so much more complex than this. The brain's decision to output a pain experience is multifactorial and completely unique to each individual - and in the case of persistent pain, is actually rarely due to a single structural reason like tissue damage.

Similarly, if someone experiences what they would call "tight" hips ("tight" of course being a vague, subjective word with no single definition for all bodies), the possible reasons for this tightness are many and varied, from a restriction in the capsule of the joint itself (which would not be addressed by passive stretching) to issues in how the brain is coordinating muscle activity (more of a motor control/neuromotor issue that is also not solved by passive stretching). Therefore, when we as a yoga community assume that the solution to all inflexibility issues is to stretch our tissues out in poses like pigeon pose, we are missing a much larger picture of how flexibility, performance, and joint function works.

This image of pigeon pose that I found online makes me feel weird. :)

This image of pigeon pose that I found online makes me feel weird. :)

WHY I SKIP PIGEON POSE - REASON #2

With all of that said, this isn't the only reason that I choose to skip pigeon pose in my classes. Even though passive stretching is not the universal solution to inflexibility issues that we yogis tend to believe it is, it still has some nice benefits, and I certainly include some passive poses in my classes. But pigeon pose also happens to incorporate some precarious joint positioning for the front knee and hip with the added weight of the torso and upper body lying on top of them, which isn't necessarily beneficial for these joints. Although there are ways to modify the pose to support these joints in a healthy way, these options are rarely offered or taught in detail in most yoga classes. And even if they were, most yoga studios don't have enough props to support every student the way they would need to be set up for optimal loading of the front knee and hip.
 

THREE ALTERNATIVES TO PIGEON POSE

And so, without further ado, I present to you... three alternatives to pigeon pose! These are three excellent ways that a pose like pigeon pose can be practiced, but with the added benefit of positive change for the tissues of the hip and a more efficient path toward increased flexibility. You'll notice that all three examples incorporate some degree of muscle activation (versus assuming the poses passively). This is because research has suggested that strengthening muscles through their full range will result in more flexibility gains faster than passive stretching alone. This is likely because when we actively contract our muscles during a stretch, this signals our nervous system that this range of motion is safe, and our nervous system will therefore be more likely to allow more range of motion in the future. Additionally, when we contract our muscles during a stretch, we load our connective tissues via muscular force, which increases their load-bearing capacity (i.e. their strength) over time. Strong connective tissues equals strong, efficient movement, functional joints, and decreased risk of injuries in the future.

Consider offering these options as an alternative to traditional pigeon pose in your yoga classes, or if you find yourself in a yoga class in which pigeon pose is taught, consider trying one of these "pigeon-ish" poses instead. (Just for the record, I don't think pigeon is an absolutely terrible pose, and I would certainly not "judge" a yoga teacher for including it in their class - pigeon is extremely ubiquitous in our yoga community and it sometimes feels like our students almost expect it. But once you learn a bit more about current stretching science and the connection between strength and flexibility, you might be inspired to change up what you offer to reflect these new understandings.)

If you decide to experiment with these pigeon alternatives, notice how it feels to strengthen your hips instead of passively stretch them in this classic pose, and enjoy the benefits that these new movements offer to your body and mind! (Also be sure to check out the further reading resources listed below these videos...)

 
 
 

Further Reading & Exploration

Blog Post: Resistance Stretching with Charlie Reid & Jules Mitchell

Related Online Workshop by Jenni: Re-Imagining Hip Openers: A Yoga Anatomy Workshop

Related Online Class by Jenni: Hips-Focused Practice #2

Related Blog Post by Jenni: Stretching Is In Your Brain: A New Paradigm of Flexibility & Yoga

Super Cool Anatomy Fact #53

 

(This is a little factoid that I shared on my yoga FB page, and I thought I'd also share it here on my blog because it's a pretty important concept for yoga teachers to understand. It's not a full blog post like my usual ones, but I have some more of those coming soon. :) )

SUPER COOL ANATOMY FACT #53: You probably know that your muscles move you around, but did you know that your connective tissue plays an important role in moving you around too? It's harder to picture because we know that our connective tissue doesn't actively contract like our muscles do. But our connective tissue actually stores what's called *potential energy* when it lengthens.

Think about this frog here. When this frog decides to jump, it first moves into a crouch, which stretches its tendons & other connective tissues, loading them with potential energy. When the frog releases this position, it certainly uses its *muscles* to propel itself forward, but its jump is hugely enhanced by the stored potential energy that was loaded into its connective tissues. It would never jump as impressively far if it didn't have its spring-like connective tissue to propel it much further than its brute muscle force alone could.

We humans rely on properties like this when we move too. It's therefore important to keep our connective tissue healthy for optimal energy storage and force transmission. One great way to cultivate healthy connective tissue is to integrate active stretching into your yoga/movement practice. When we strength-train our tissues at all ranges, we signal our connective tissue to grow stronger and stiffer ("stiff" being a good thing when we're talking about connective tissue!) We don't create healthy, efficient tissues by pulling on them and trying to make them longer - we create strength and resiliency in our tissues by making them stronger at all ranges.

Try thinking less about "length" and more about strength and efficiency in your yoga/movement practice and see if your flexibility magically improves anyway! My new hamstrings-focused online yoga practice is a great place to start if these ideas are newer to you. :)

Hamstring Strengthening for Yogis

I recently wrote a blog post that questioned the widespread belief that strengthening muscles makes them "tighter". In the post, I focused on the hamstrings as my main example, because so many people have "tight" hamstrings, but they are generally not recommended to strengthen them due to a belief that this would only make them tighter. Additionally, we spend a lot of time stretching our hamstrings in yoga, but very little time strengthening them.

Can you tell that I think hamstring-strengthening is a good idea, especially for yogis? :)

This video demonstrates one method of strengthening the hamstrings that can easily be included in any yoga class. I love this move and hope you have fun trying it out!

Fact Check: Will Strengthening Your Tight Hamstrings Make Them Tighter?

In any given yoga class, we are bound to practice an abundance of poses which stretch our hamstrings and relatively few that actually strengthen them. This rarely-discussed imbalance in yoga sequencing tends to occur for two main reasons.

First of all, there simply aren’t that many yoga asanas out there which strengthen the hamstrings in a meaningful way. Even if a yoga teacher wanted to focus specifically on hamstring strengthening in a particular class, she would have very few options in the traditional yoga pose canon from which to choose. Second, yoga teachers are well aware that many of their students have “tight” hamstrings, and there is a conventional belief in the yoga world (and in the fitness community in general) that it is not advisable to strengthen “tight” muscles because it will only make them tighter.

Today we’ll focus on the latter of these two issues: the idea that we should avoid strengthening our tight muscles because they are already tight. This is a very common and completely understandable belief among yogis. After all, one of our foundational goals in our yoga practice is to cultivate balance in our body. With this goal in mind, one of the last things we would want to do is create more tightness in an area that was already tight-feeling to begin with.

 

BUT WHAT DO WE MEAN WHEN WE SAY “TIGHT”?

Surprisingly, the widely-used term “tight” often means quite different things to different people. The following are all possibilities for what someone could be describing when they say they are “tight”:

-they aren’t able to stretch very far in a given direction
-their actual experienced sensation of their muscles when they stretch is “tight”
-the general, perpetual state of a specific muscle or group of muscles in their body is tight (i.e. “my hip flexors are tight from sitting so much”)
-they experience a vague sense of achiness or discomfort somewhere in their body (i.e. “my low back feels stiff and tight”)
-something else entirely :)

The reality is that there is ultimately no science-based definition for the word “tight”. The term is a very subjective one that each person experiences uniquely in his or her own body. This lack of an actual physiological definition for “tight” throws into question the very basis for the “strengthening tight muscles makes them tighter” belief. If there is no clear mechanism for what “tight” is, any rule about the body based on this concept begins to lose its meaning.

 

ARE TIGHT MUSCLES SHORT MUSCLES?

Although the notion of “tight” lacks a physiological definition, one commonly-shared belief about tightness is that the muscle(s) in question are shorter than they should be, and the natural solution to their “tightness/shortness” is to therefore lengthen them back out by stretching them.

This has been the dominant paradigm regarding stretching and “tight” muscles in the yoga world (and the fitness community in general) for many years. In my 2-part blog post series Stretching Is In Your Brain, I discussed that in contrast to this “short muscles that need to be lengthened” idea, a more updated, research-based perspective on stretching is the notion that our body’s flexibility is instead governed by our brain and central nervous system via a mechanism called stretch tolerance. [See study.] In summary, our inflexibility is not due to physically short muscles - it is instead due to our brain putting the brakes on our movement because it perceives that any deeper of a stretch will not be safe for us (and it’s probably right!) The “tightness” feeling that we experience at the end of our stretch is not the feeling of short muscles reaching the end of their length, but of an output of our brain in response to our stretch designed to signal us to stop the movement.

Isn’t this a fascinating and possibly mind-bending new way to approach the body in terms of stretching and our yoga practice?

 

STRENGTHENING THOSE TIGHT HAMSTRINGS

The hamstrings muscle group: biceps femoris, semitendinosus, & semimembranosus. (Image courtesy Real Bodywork, Inc.)

The hamstrings muscle group: biceps femoris, semitendinosus, & semimembranosus. (Image courtesy Real Bodywork, Inc.)

Paradigm-shifting aside, let’s return to the main topic of this article, which is the common belief that strengthening a tight muscle will make it tighter. In the same way that we tend to believe the outdated idea that our inflexible muscles are “short”, we also tend to believe that strengthening a muscle will physically alter that muscle so that it becomes shorter.

For example, the hamstrings might be the number-one-cited area of “tightness” in the average body. (But remember that “tightness” is a non-specific term without true scientific meaning.) If we believe that our hamstrings are “tight” because they are short, and if we also believe that strengthening muscles will physically shorten them, then there is no way that we would ever think that strengthening our short, tight hamstrings is a good idea. Tight plus tight equals more tight, right?

In addition to the example of the hamstrings, here are a few other areas of the body to which we often apply this same logic:

-our hip flexors are short from too much sitting, so we shouldn’t do hip flexor-strengthening moves

-our spines are rounded-forward (hyperkyphotic) from too much slouching, so we shouldn’t practice traditional abdominal work because it would shorten our abdominal muscles and pull us into more of a slouch

-our calves tend to be tight from high-heel (and other positive-heeled shoe) wearing, so we wouldn’t want to strengthen our calves because it would further tighten them

These arguments would absolutely make sense if we were still operating under the paradigm of physically-short muscles that we lengthen back out by stretching. But in the same way that we now understand that stretching a muscle doesn’t make it “longer”, we have also learned that strengthening a muscle does not make it “shorter”. Or to be more accurate, there is very little (if any) evidence to support the idea that strengthening a muscle causes it to structurally change so that its resting length becomes shorter.

As counterintuitive as it may seem (believe me, I know!), strengthening muscles does not “tighten”, “stiffen”, or “shorten” them - it doesn’t decrease their flexibility in any way. [See study.] In fact, if we strength train our muscles eccentrically (which means that our muscles are active as they lengthen), this has been shown to actually increase their flexibility. [See study.] So not only does strengthening a muscle not physically shorten it, but if done correctly, it can increase its stretch tolerance. This seems so contrary to popular thinking, but once we understand that our muscles only do what our powerful, communicative, and dynamic central nervous system tells them to do, these concepts begin to make more intuitive sense.

One important note is that while strengthening doesn’t stiffen our muscles, it will stiffen up our connective tissue (which is distinct from, although interwoven with, our muscle tissue) - but this is actually a desirable outcome. As I discussed in Stretching Is In Your Brain Part 2, we want our connective tissue to be stiff so that it can be strong, resilient, and less vulnerable to injury.

IN CONCLUSION...

In circling back to the overarching question of this article: no, strengthening your tight/short hamstrings (or any other muscles) will not make them tighter/shorter. But it will make the connective tissue of your hamstrings stronger and less prone to injury. This is especially relevant for yogis, given the high incidence of hamstring pulls and strains we experience in the yoga community as a result of the traditional sequencing of lots of hamstring stretching and very little strengthening. With this new knowledge about muscle physiology in mind, we should feel encouraged to strengthen any area of our body we might have previously been avoiding because we were afraid it would “tighten” up as a result. This change in approach will represent a path toward greater body awareness and the true balance that so many of us seek through our time on the yoga mat.

 

Related Online Workshop: Re-Imagining Hip-Openers: A Yoga Anatomy Workshop

Related Online Class: Hips-Focused Practice #2

The Easiest Mistake to Make in Backbends

I am sooo thankful to have published a second article in Yoga International! It's all too easy to do backbends in a way that will make your spine mad at you :), and I hope this article will provide lots of helpful info for how to approach these poses in a way that will offer true positive change in your body. Thanks so much for reading, guys!

https://yogainternational.com/article/view/the-easiest-mistake-to-make-in-backbends

In other news, I'm working on a new series of posts for my blog on shoulder mechanics in yoga. I haven't written specifically about the shoulders here yet, so I'm hoping that these posts will help fill in some missing info on this important area of the body. Stay tuned for this and more great movement info to come!

Stretching Is In Your Brain Part 2: What Is The Value Of Flexibility Without Strength?

In Part 1 of my “Stretching Is In Your Brain” series, we looked at some updated information on what happens physiologically inside of us when we stretch. To re-cap, new science is revealing that the widely-held belief that we physically grow our muscles longer during a stretch is inaccurate. Instead, flexibility is controlled by our nervous system, which determines how far it will allow us to move into a stretch based on how safe it perceives our body to be in that range of motion.

As yoga practitioners and teachers, we’ve been treating our muscles as though they are independent entities which we can mold through direct manipulation, but in reality our muscles are just the peripheral, subservient component of a much broader system of communication and control. Let’s explore some of the implications that this major paradigm shift has for how we approach the body in our yoga practice.

 

WHAT DOES PULLING HARD ON OUR TISSUES ACHIEVE?

In the old paradigm of stretching in which we believe that we’re physically pulling our tissues longer like taffy when we stretch, it would logically follow that in order to gain more flexibility, we should simply pull harder and deeper. Wringing oneself deep into a spinal twist or receiving a strong adjustment from a teacher intended to push your range of motion further are common examples of this strategy. But we now understand that flexibility is much less about using brute physical force to grow our muscles longer, and much more about using intelligent communication to suggest to our nervous system that a particular range of motion is safe.

In fact, the “brute force” method of stretching is problematic in multiple ways. When we stretch, our muscles aren’t the only tissues that are affected. Muscles are surrounded by and interpenetrated with fascia, which also makes up the body’s ligaments and tendons. When we move our body into a stretch, both our muscles and our fascia experience the stretch at the same time.

It’s important to understand that fascia has only a set range that it can stretch. Stretching offers many benefits to the health of our fascia, but it won’t change the range of this tissue. This means that after fascia experiences the load of a stretch, only one of two possibilities can happen: 1) it returns to its original length after being stretched or 2) it is stretched too far and is damaged. And that’s it! We don’t make our fascia “longer” when we stretch. And if we pull too hard on this tissue in an effort to elongate it, we will most likely move beyond its ability to withstand the load, which will ultimately lead to injury. As counterintuitive as it may seem, for the health and balance of our structure, we actually want our fascia to be quite “stiff” and “resilient”.

 

BUT HOW MUCH STRETCH IS THE RIGHT AMOUNT?

We understand that stretching intensely does not benefit us, but how do we know where that boundary lies in our body as well as our students’ bodies? Here’s a key rule to use in your practice: when we stretch, we should only move into a range of motion over which we have muscular control. This is because our nervous system feels safest when it senses that we have control over our movement.

Put another way, we don’t want to create flexibility without the strength to support it. If we stretch within these parameters, our practice is likely to contribute to a balanced body that moves well. However, when we stretch into a range in which the targeted muscles cannot function, we are creating excessive mobility (and more than likely hypermobility) that we don’t have the ability to stabilize. 

Hanumanasana, yoga's forward split.

Hanumanasana, yoga's forward split.

To illustrate this point, let’s look at hanumanasana, yoga’s forward splits. If we practiced this pose with the goal of building flexibility within the context of strength, we would only move as deep into the shape as the muscles of our legs could maintain control. Picture it: without using your arms pressing into the floor, you would slowly lower down into your full hanumanasana and then use those very same leg muscles to lift yourself all the way back up (again, without the use of the arms!) This might seem like a superhuman acrobatic feat, but I promise it would be possible if you truly worked to build power at your end range.

My friend Maddy demonstrating gomukasana arms.

My friend Maddy demonstrating gomukasana arms.

Let’s touch in on a few other asanas to see how this “stability at your end range” principle might apply. Padmasana, or lotus pose, is one of yoga’s classic asanas. Most of us use our arms to pull our legs into this shape. We also sometimes use momentum to quickly fold our legs into lotus, but momentum is another method of moving into a range of motion that we don’t have the strength to control. Is it any wonder that padmasana is notorious for tearing soft tissue in many a yogi’s knee joint? Try this instead: without using your arms or momentum, use only the muscles of your legs to fold your feet as close to your hips as you can and breathe there. This shape - one over which your muscles have control - is the correct stability edge for your body. Another great example is ekapadasirsasana, yoga’s leg-behind-the-head pose. If that leg can climb behind your head itself, without the use of your arms, then you’re staying within your excellent strength-at-your-end-range limits. But I have yet to see a yogi who can accomplish such a daunting task! A less obvious pose in which we commonly move beyond our stability edge is gomukasana, or cow-face arms. Many people like to use their opposite arm to help that bottom arm climb higher up the back, but as soon as we interfere with that bottom arm’s own ability to move itself to its edge, we are stretching past our active range of motion and into unsupported mobility.

 

IN CONCLUSION...

I know that so many of us yogis are used to going as deep as our bodies will allow in our poses. Think of the innumerable beautiful photos that yoga teachers have in their portfolios or on Instagram of their bodies looking extremely graceful in a perfectly-executed forward split. (I don’t personally have a photo of myself in hanumanasana, but I certainly have photos of many other asanas in which I’ve moved well beyond my active boundaries.)

The science behind utilizing stability as a container for flexibility is not yet widely understood in the yoga world - and not surprisingly, the number of overstretching injuries in our community is quite high. But as a yoga community, we have to ask ourselves some tough questions: if you have the mobility to move deeper into a pose than your muscles can control, where is that mobility coming from, what is it offering you in terms of how well your body functions, and how many more times can you practice this pose before an injury occurs? What is the value of flexibility without the strength to support it? This is the kind of shift in thinking that yoga needs to make if we want our practice to truly offer the structural health and other long-term benefits like aging with ease that so many yoga practitioners seek.