[Microblog] Our Bodies Are Naturally Asymmetrical

I don't know how many images of lungs you've looked at, but have you ever noticed that our two lungs are not symmetrical? Check out this medically-accurate image that shows that the right lung has 3 lobes while the left one has 2, and the left one is also a bit smaller than the right to make room for the heart.

Even though we sometimes hold up balance and symmetry as an ideal that we should strive for in our bodies, as though being "imbalanced" is inherently problematic, the truth is that our bodies are not actually evenly-balanced left-to-right to begin with. We don't need to look or feel even on both sides of our body in order to be healthy, functional beings. Asymmetry is a natural part of who we are!

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] There is No "Right Way" To Do A Yoga Pose

hovering-pigeon.jpg

When I think about yoga alignment, the approach I take these days is that there is no one "right" way to practice any yoga pose. The right way to align a yoga pose really depends on who is practicing the pose and what their individual goals are. Our goals can also change every time we practice a pose, and that's actually great. Otherwise we just practice the same thing the same way all the time and never provide new input into our tissues or our nervous system.

In this "hovering" variation of pigeon pose, my goal is to create *strength* in my hips in a pigeon-like joint arrangement. This is good stuff that will create tissue health and neurological control in my hips - something that nearly all of us can use more of. Consider changing up your pigeon pose regularly and all your other poses too - as long as they align with your specific goal in the moment, then that is "right" way for you to practice the pose.

Top 5 Movement Science Insights For Yoga Teachers

These are 5 of the most eye-opening insights I have learned from anatomy, physiology, kinesiology, and pain science that have given me a much different perspective on the body than the one I learned through my yoga studies alone. I hope you find these ideas interesting and inspiring for your own yoga practice and teaching!

Each of these insights is simply my best offer at a summary and takeaway for yoga teachers who might not have the time or interest to study these issues thoroughly on their own. There are volumes more to be read about each of these points from primary and secondary sources, so feel free to investigate the links and references I've included below, or to do your own research on these topics to help you come to your own conclusions.

If you're interested in how one might embody these Top 5 insights in their yoga teaching, consider trying some classes in my online class library, which is a great resource of practices from myself and other wonderful science-minded yoga teachers I admire.

Please read the insights below with a willingness to question your own biases and an openness to incorporate critical thinking into your approach to yoga and movement. Without further ado, here are my Top 5 Movement Science Insights For Yoga Teachers!

 

 

MOVEMENT SCIENCE INSIGHT #1: STRETCHING & STRENGTHENING ARE NOT OPPOSITES

One of the core rules we tend to learn in our yoga teacher trainings is that after we've "worked" or “strengthened” a muscle or muscle group, we should then stretch the area to lengthen it back out and restore "balance". The reasoning behind this rule is usually that when a muscle "works" or "contracts", it is shortening. Therefore to avoid leaving your muscle in an excessively shortened state, you should balance it out by "lengthening" or "stretching" it after you've worked it.

This idea would make sense if muscles did only shorten when they contract. But shortening while contracting is actually only one part of the physiological equation - muscles work just as often as they lengthen too. Picture your hamstrings and the way they lengthen while they're working 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. [Ref]

Because muscles can and do actually contract through all of their ranges (short, long, somewhere in between, etc.), it is clear that the physiological opposite of a muscle contraction is not a stretch. With this in mind, it might be time to re-think our classic "strengthen it, then stretch it" rule!

 

MOVEMENT SCIENCE INSIGHT #2: NO YOGA POSES ARE INHERENTLY "BAD" OR "GOOD"

Last year I wrote a blog post called Are Some Movements Inherently Bad? which basically suggested that no movements are inherently “bad”, and the only truly bad movement is one for which your individual body is not prepared or conditioned. But the inverse of this insight is also true. While no movement is inherently bad, no movement is inherently good, either. There is a trend in the yoga world toward teaching yoga poses and other movements like “corrective exercises” that are thought of as "better", more "functional", or "healthier" for the body. But the reality is that movements don't have inherent value (i.e. "better for you", "worse for you", etc.) outside of the specific context of who is practicing the movement and with what goal in mind.

We honor the complexity of the human body and its relationship to movement when we avoid valuing certain yoga poses and movements as inherently better, more functional, or worse than other yoga poses and movements. Context and individualized goals are the main determinants of what makes a movement “good”, “bad”, “functional”, or “dysfunctional”.

 

MOVEMENT SCIENCE INSIGHT #3: ALIGNMENT IS LESS ABOUT INJURY-PREVENTION AND MORE ABOUT LOAD-OPTIMIZATION

We generally learn in our yoga teacher trainings that alignment is important in yoga poses primarily because it prevents injuries. However, we’re now learning that the categories of alignment, injury, and pain are not as interrelated as we have previously been taught. Many people exhibit “poor alignment” and are pain-free, while many others exhibit “stellar” alignment and have chronic pain (and to make matters more confusing, pain and injury (i.e. tissue damage) are also not always correlated either.) [Link]

It turns out that the human body is more resilient and adaptable than previous models of alignment and pain have accounted for. Our body actually has a remarkable ability to adapt to become stronger in response to the loads it experiences (as long as those loads aren’t beyond the ability of our tissues to withstand.) [Link] Therefore if we habitually position ourselves in a way that is different from “ideal alignment”, it’s less likely that our body will sustain inevitable damage from the “misalignment” and more likely that our body will simply adapt to better handle the loads of this alignment. (This is assuming that the joints in question are asymptomatic and healthy, of course!)

Now in a high-load situation, such as squatting in the gym with a 300-pound barbell on one’s back, alignment is undeniably an important tool for minimizing risk of injury. [Link] Activities like this involve high forces that are more likely to be beyond the ability of our tissues to withstand, and so aligning our joints intelligently is definitely recommended.

But compared to heavy weightlifting scenarios, yoga is for the most part a low-load activity. Small variances in alignment under low load are not enough to cause inevitable injury and damage in most bodies. For example, if someone’s front knee drifts inward a few centimeters in warrior 2 (breaking the classic alignment rule of keeping the knee stacked directly over the ankle), the tissues of the knee will most likely respond to that load by adapting to become stronger at that angle. And if the shoulders drift slightly out of “joint-stacked” alignment over the wrists in plank pose, the shoulders, elbows, and wrists should be signaled to grow stronger and better able to handle load from this new angle.

In fact, exposing our body to variable loads like this is actually a great way to prevent injury because it helps condition our tissues to become stronger at all angles, rather than strong in only the classic “joint-stacked” position of traditional alignment rules. I would argue that increasing the ability of one's tissues to tolerate load by strengthening the body at all angles and ranges is a much more effective strategy for injury-prevention than "alignment" is.

These days I view alignment as a tool that helps my students direct the loads in their bodies where I intend for those loads to go, rather than as a necessary tool for injury-prevention.

 

MOVEMENT SCIENCE INSIGHT #4: WE USE TOO MUCH FEAR-BASED LANGUAGE AROUND ALIGNMENT IN YOGA

This insight piggybacks right onto insight #3. It’s very common in the yoga world to pepper our alignment instructions with cautionary language, such as “Align your front knee right over your ankle in Warrior 2 to protect your knee” or “Press your pubic bone into the floor in shalabhasana to keep your low back safe.”

As well-intentioned as they are, warnings like this can actually serve to instill a false sense of fragility in our students, which can counterintuitively result in their experiencing pain. We know now that pain is a creation of the nervous system in response to a perceived threat. And our beliefs about our body are actually one influence that can directly escalate or de-escalate our nervous system’s perception of threat and output of pain. [Ref], [Ref], [Ref] Therefore the more we trust in the robustness and resiliency of our body, the more we communicate a message of confidence to our nervous system, which is likely to result in lower threat levels and decreased pain. And conversely, the more we believe that our bodies are innately fragile and vulnerable to injury from low loads and small micro-“misalignments”, the more likely our beliefs are to contribute to increased threat levels and increased pain.

In warrior 2 pose, stating that keeping the knee directly above the ankle is important “to protect your knee” is a potentially nocebic suggestion to offer to our students. (A nocebo is a negative expectation of an otherwise harmless event or action that causes negative consequences like pain.) Likewise, stating that the pubic bone should stay grounded in shalabhasana “to keep your low back safe” suggests to our students that their spines are fragile structures that will experience damage if their pelvis is tilted a few millimeters in the “wrong” direction.

Instead of using cautionary, nocebic language about alignment in our yoga classes, consider talking about alignment in terms of what it helps us achieve in our poses. For example, in warrior 2 we could say “Keep your front knee lined up over your ankle to engage your lateral hip muscles” or “Press your pubic bone into the floor in shalabhasana to lengthen your low back and direct the backbend into your thoracic spine.” These types of cues utilize alignment more for load-optimization reasons and less for injury-prevention reasons. Instead of instilling a sense of fragility about their bodies, these types of cues encourage increased body awareness in our students, which can be confidence-building and empowering.

 

MOVEMENT SCIENCE INSIGHT #5: TWO COMMON YOGA CUES WE CAN STOP USING

We often teach yoga poses in a way that tells our students which specific muscles they should (or should not) be contracting in particular movements.

In certain contexts, suggesting which muscles a student should be using at any given time can be a useful type of guidance. But it's helpful to realize that as a general rule, our nervous system actually does a good job of automatically organizing and coordinating the movement of our body all on its own, without needing much conscious input from our thinking mind. In fact, consciously "micromanaging" which muscles our nervous system chooses to recruit can often interfere with our built-in, sophisticated motor control system in a way that results in less efficient movement. [Ref]

With this in mind, here are two cues that are very common in the yoga world today that we could all use to stop giving:

1) The glutes & bridge/wheel: there is no need to tell our students that they should "soften their glutes", "relax their glutes", or otherwise disempower the main muscles of hip extension that their bodies naturally recruit when they lift their hips up into bridge pose (setu bandha sarvangasana) and upward-facing bow pose (urdhva dhanurasana). [Ref]

2) Arms overhead & shoulder positioning: there is no need to cue our students to "pull your shoulders down your back" when their arms are overhead. When our arms lift up, our shoulder blades naturally rotate and lift along with the arm movement. [Ref] This is a normal, optimal movement that is often referred to as "scapulohumeral rhythm", and it is not helpful to interfere with this natural coordinated action by trying to consciously pull the shoulder blades down the back to prevent them from lifting.

 

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

Podcast Interview: Pain Science For Yoga/Movement Teachers

I was lucky enough to get to talk about pain science and what implications it has for us yoga/pilates/movement teachers on the wonderful Moving Well podcast! Nikki Naab-Levy and Janet Sunderland are the very smart and engaging hosts of this podcast, and I really enjoyed having the opportunity to talk with them about one of my favorite topics to geek out about. :)

I hope you enjoy the interview if you have the chance to listen to it!

Fascia Myths and Fascia Facts

Have you noticed that the word “fascia” has become somewhat of a buzzword in the yoga world lately? There have been lots of articles written about this newly-appreciated bodily tissue (I myself have written two of them in the past few years!), and fascia has become a focus in many yoga classes - especially those that include rolling on self-massage tools like balls and foam rollers.

I understand this preoccupation with fascia, because it is a truly fascinating topic. Fascia is a type of connective tissue that forms a continuous body-wide web inside of us, surrounding and interpenetrating all of our muscles, bones, organs, nerves, and blood and lymph vessels. In fact, in addition to forming the architecture that weaves our inner structures together, our connective tissue system as a whole also absorbs and transmits force inside of us, working in conjunction with our muscular system to create smooth, efficient movement. Such insights have the power to expand the way we understand movement, which is very exciting!

In addition to these inherently interesting facts, there are other claims commonly made about fascia that are widely-believed, but reach a bit too far ahead of the research to be actually supported. Today I’d like to address a few of these specific claims in an attempt to encourage our yoga community to embrace a more science-based, productive dialog about the popular topic of fascia and the wonderful practices of massage and rolling.

 

MYTH #1: ROLLING ON BALLS AND OTHER MASSAGE TOOLS BREAKS DOWN FASCIAL ADHESIONS, KNOTS, AND SCAR TISSUE

Every massage therapist knows the experience of finding a tight spot in her client’s body, massaging it, and feeling it “release” or “relax” underneath her hands. It seems natural to assume that through her hands, she physically broke down a knot in her client’s fascia - and that through rolling on massage tools, we can do the same to ourselves too.

But one lesser-known fact about fascia is that its collagen fibers are literally as strong as steel. [Ref] To actually “break them up” would require so much force application that one’s body would sustain serious injury - this is not something that is achieved by a massage therapist’s hands or by a pair of massage balls.

Although you may feel a tight spot in your body change its texture after rolling or being massaged, this change was not due to the architecture of the fascia changing. For fascia to actually change its architecture, many, many inputs are required over a long time - collagen takes about three years in order to completely change and remodel. [Ref] Any instantaneous changes in tissue quality that you experience as the result of a massage are not the “breaking down” of adhesions, knots, or scar tissue - they are instead changes in tissue tone that are mediated by the nervous system. [Ref]

Once we understand that soft tissue treatments like massage and rolling work primarily via neurological communication instead of via physically breaking down adhesions, knots, and scar tissue, we might be encouraged to administer these treatments more gently than forcefully. When we roll and massage ourselves with deep, forceful pressure, this can often increase nervous system threat levels and sensitivity, which can be counterproductive to our efforts. Gentler, milder work is often more successful at decreasing threat levels and coaxing the nervous system to relax our tissues.

Massage and rolling on balls are undeniably wonderful, potent tools that help so many of us feel better in our bodies, but when we understand more about the mechanism for why they work, we will naturally be able to use them more wisely.

 

MYTH #2: WE FEEL PAIN IN OUR BODY BECAUSE OUR FASCIA IS FULL OF KNOTS, ADHESIONS, AND SCAR TISSUE

This is a very common belief, but it turns out that it is based on some inaccurate information about how pain works. I’ve written about the science of pain before [here and here], but one of the most foundational aspects of pain is that it is an output from the central nervous system, not an input from the periphery. It’s easy to be confused about this concept because when we feel pain, we feel it in a particular area of our body. It feels like the pain is in our tissues, and it’s our tissues that are therefore causing it. But the pain doesn’t actually reside in our tissues at all - it is 100% an experience that our nervous system has created for us to perceive - most likely to serve as some sort of protective signal.

Because pain is an output and not an input, adhesions, knots, and scar tissues - which are located in the periphery of our body (if they exist at all - but that’s a whole other topic!) - are not actually capable of creating pain. This concept might be tough to grasp, especially because we know that a massage therapist can touch a certain “knotty-feeling” spot on our body and it might feel tender or painful. But the pain you feel there was not created by the knot - it was created by your brain and experienced in that spot. Additionally, we know that we can have other painful-to-the-touch places in our body that do not actually correspond with a “knot” or tight spot that resides there. The flesh in those painful spots instead feels smooth and knot-free. And there are probably quite a few other locations in your body that definitely feel “knotty”-like when palpated, but are not associated with pain at all. [Ref]

As it turns out, pain and tissue quality are separate entities that sometimes overlap, but oftentimes do not. While it's easy to believe that all tight spots underneath our skin are problematic, the truth is that many of them are probably just normal, healthy variations in our tissue texture. And pain, regardless of where it is felt in the body, has less to do with knots, adhesions, and scar tissue, and more to do with a nervous system that has been sensitized around a particular area. This is a helpful, progressive change in perspective because the less that we pathologize the physical feel of "tightness" and "knottiness" in our tissues, the less likely we are to create nocebos for ourselves or our yoga students and massage clients. (A nocebo is a negative expectation of an otherwise harmless event or action that causes negative consequences like pain.)

 

MYTH #3: OUR FASCIA CAN BECOME DEHYDRATED AND ROLLING ON MASSAGE TOOLS HELPS TO RE-HYDRATE IT

This is an absolutely appealing and intuitive idea, but to the best of my knowledge, we don’t have research that supports this claim. Part of the problem lies in a lack of specificity for how this proposed dehydration/rehydration process would work.

An artist's depiction of connective tissue.

An artist's depiction of connective tissue.

In simple terms, our connective tissue is made up of cells, collagen fibers, and a non-living gelatinous matrix called ground substance. When the claim is made that fascia can be dehydrated, I believe the notion is that its ground substance is dehydrated.

It’s unclear to me how it could be determined that someone’s ground substance is dehydrated, however - can you tell by looking at someone from the outside? Maybe by looking at their skin? Can you tell because they feel pain somewhere? (As we mentioned earlier, pain and tissue quality are poorly correlated.)

Even if there was a reliable way to assess fascial dehydration, it is unclear to me how a massage or rolling on balls or other tools would hydrate it. The ground substance of connective tissue definitely has some water content, but how would the pressure from rolling change this water content? (Water that you drink goes through different channels in your body than water in your ground substance, so that's a different type of hydration than fascial hydration.) Does rolling add new water to fascia (how?), or does it move already-existing water from another part of the body to the deydrated one? If rolling did increase water content, wouldn’t everyone’s glutes be extra hydrated and especially healthy because so many of us squash them with pressure by sitting on them for hours every day?

Most of us believe this hydration claim because we heard it from someone knowledgeable like a smart yoga instructor or an experienced bodywork teacher. But if we actually look to connective tissue biology for some factual basis to the claim, we find that there is little support there. It may be true that massage can hydrate our dehydrated fascia, but research has not yet demonstrated this in a clear way. I believe we would do more of a service to our yoga community by waiting to make claims like this until science begins to produce some solid evidence for them.

 

In summary, fascia is an incredibly fascinating tissue of the body for an abundance of reasons. But we will better serve ourselves and our students if we shed some of our language about fascia that implies that it is full of painful adhesions and scar tissue that need to be broken down and hydrated. Additionally, massage therapy and self-massage tools like balls and foam rollers are absolutely wonderful, helpful practices that offer great results for so many people. But when we recognize and teach an awareness of the often-overlooked role that the nervous system plays in many of these massage benefits, we will be able to utilize these tools even more powerfully for ourselves and our students and clients.

 

(If you're interested in exploring these ideas further, you might appreciate this video from Quinn Henoch, Doctor of Physical Therapy:)

[Microblog] A muscle isn't a muscle to your brain

We tend to think of muscles as the individual, isolated structures that we see in our anatomy books - the biceps, the hamstrings, the psoas (or to be super geeky, *psoai* if we're talking about 2 of them), etc. But did you know that this is NOT how your brain understands muscles?

Your brain doesn't actually know what a "psoas" or a "biceps" is. These are arbitrary names that we give to our parts so that we can learn and communicate about them (which is a good thing!) But the brain doesn't think in terms of individual muscles - instead, it perceives and directs *motor units*, which are tiny subsets of individual muscles.

In this sense, we could really think about each muscle as actually being made up of thousands of smaller muscles, which are where movement truly happens in the body.

Whoa man!

[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!