EXPERT Q&A ON YOGA, STRETCHING & INJURIES W/GREG LEHMAN

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As a member of the yoga community for many years, I regularly hear claims made about how stretching affects the body. These claims vary widely, and I’ve heard everything from “stretching is a magical cure that will heal all of your ailments” to “stretching is damaging for the body, and therefore yoga is bad for us.”

I try to be as evidence-based as possible in my approach to yoga, so I’m naturally skeptical of claims that appear to lack scientific support. In order to clarify some of the truth versus fiction regarding stretching for both myself and the greater yoga community, I decided to consult with an expert who is extremely up-to-date on the most current scientific research on stretching.

Dr. Greg Lehman, BKin, MSc, DC, MScPT, is a Clinical Educator, Physiotherapist, Chiropractor, and Strength and Conditioning Specialist. He travels the world teaching his Reconciling Biomechanics with Pain Science course to health & fitness professionals. He is also the creator of the “Recovery Strategies” pain workbook, which is an amazing, informative, and free resource for anyone in pain. Greg’s work has had a profound impact on the therapeutic, fitness, and yoga/movement worlds, and I am incredibly honored to feature his insight on my blog!

YOGA & STRETCHING Q&A W/GREG LEHMAN

QUESTION 1: In the yoga world, there is a widespread claim that stretching can lengthen connective tissues like ligaments & tendons, causing them to become lax and leading to "joint instability". Is this a biologically plausible assertion?

ANSWER: There is no evidence that this actually happens.  Pretty unbelievable, eh? There is certainly more evidence that suggests when you pull (apply tension) to connective tissue it responds by getting stiffer, stronger and sometimes thicker.  Old research by Dr. Woo has shown this consistently.  The only consistent thing that can make connective tissue less stiff is immobilization and injury.  So, it is possible that people who gain massive amounts of flexibility may have at some point damaged their tissue. 

If people feel “lax” because they stretch I would guess that it would be more of muscle or nervous system change.  People may not have the strength in those ranges to control the motion rather than the idea that they lengthened connective tissue constraints.

 

QUESTION 2: What exactly does "stability" mean when it comes to our joints, and is there evidence to support that a lack of joint stability causes pain and/or dysfunction?

ANSWER: A stable joint system just means when it gets perturbed or jostled it comes back to its resting place.  But, people have expanded the definition to mean that a joint just moves a lot when you don’t want it to move.  Joint instability is a problem when a joint pops out of place and does not readily go back into place.  It certainly does happen but I doubt it’s that common.

 

QUESTION 3: Can passively stretching a muscle compromise its strength (i.e. decrease its ability to produce force)?

ANSWER: Not significantly, meaning 1-5% of max force production [if stretching immediately prior to a strength activity].  And since we regularly don’t need to produce max force it’s not really an issue.  And you only get this transient force reduction when you hold a static stretch for 45 or more seconds.  Some research (Blazevich) even suggests that these max force/power losses are mitigated or completely ameliorated provided you do a warm up.

There is no reason to think that long-term stretching will make you weak.

 

QUESTION 4: Aside from concerns about lengthening ligaments & tendons that we've already covered here, is it inherently injurious or damaging for the body to spend time in passive end range stretches? What about for someone with a connective tissue disorder such as generalized joint hypermobility (GJH) or Ehlers-Danlos Syndrome (EDS)?

ANSWER: I think with EDS it makes sense to limit those movements and get strong instead.  That’s one of those conditions where shit really does pop out of place.  But for other people, who cares if you hang out at end range. You are just applying tensile load to tissue (pretty much what strength training does but at other ROMs) and the tissue will adapt by getting stronger. 

We aren’t made of taffy.  We don’t really “stretch” that way with applied loading like end ROM stretching.  I don’t think it’s injurious but you could certainly argue that there are better options to achieve health and mobility – like adding strength training or even resistance throughout the range of motion.

 

QUESTION 5: There is a growing dialog in the yoga world about the distinction between active & passive stretching, with a new emphasis being placed on the benefits of training active strength & control through our ranges of motion ("active stretching") and a de-emphasis being placed on passive stretching. The reasoning goes that if we have more passive ROM available at a joint than active ROM, we are more susceptible to injury because we lack "control" in those end ranges. Would you agree with this line of thought?

ANSWER: I think you should do both.  I wouldn’t be worried about injury though.  I don’t think most people are getting injured because they have lost “control” of the joint.  Further, if you get injured because the joint suddenly goes to end ROM, it’s not strength at end ROM that would have helped you - it’s the strength and control that you needed before you went to end ROM. 

 

QUESTION 6: Many long-term yoga practitioners have discovered through imaging that they have a hip labral tear, and yoga is often blamed as the cause of this tear. Given that yoga is a low-load activity and that a majority of people in general will develop an asymptomatic labral tear as they age [Ref, Ref, Ref, Ref], is a long-term yoga practice a likely cause of a hip labral tear?

ANSWER: Labral tears are common. Heck, they might even be beneficial for performance.  It’s not unreasonable to think that ANY activity can predispose you to joint changes.  They happen and I doubt there is much we can do about it.  You will see labral tears and bony changes in most sports. 

So should we stop physical activity because of the chance of a labral tear? No. There are way too many benefits from a movement practice that far outweigh the negatives of a potential increase in the chance of having a labral tear.

 

QUESTION 7: In terms of stretching physiology, I believe that many people conflate the "muscle spindle stretch reflex" (reflexive muscular contraction during a stretch) with "stretch tolerance" (tolerating the discomfort of stretching) in their minds. Could you describe the difference between these two phenomena? Do they both play a role in stopping us at the end range of a stretch?

ANSWER: I’m not sure to be honest.  Stretch tolerance definitely plays a role as the stretch is stopped (in the experimental studies) when the participant says its too much.  What happens with long term stretching is that you are able to go farther without there being a dramatic change in tissue qualities.  Meaning we assume that the changes in ROM are due to your tolerance or perhaps habituation rather than a structural change.

The muscle spindle stretch reflex is assumed to not be occurring during end ROM stretching because in these studies they monitor muscle activity.  Meaning, they try to make sure there is no measurable muscle activity that occurs at end ROM.  We assume its just a passive resistance to stretch.  However, it is plausible that there is minor amount of activity that isn’t being picked up and this could be “putting on the brakes”.

 

QUESTION 8: Do you believe there are ways in which passive stretching could actually be beneficial for the body on a musculoskeletal level? If so, how?

ANSWER: Yes.  I think long term stretching is just passive tensile force and tension has the ability to create positive structural adaptations in tissue.  Some (Kubo) have argued that passive stretching can make tendon more efficient.  Others suggest that passive stretching influences muscle stiffness which might be good to balance the stiffness changes in a tendon that can occur with injury.

I certainly don’t view stretching as a negative which I once did.  I think if you argue against stretching you are really not “against” stretching but more pro some other intervention.  So, if you like to stretch and its helpful for you I would encourage you to keep it up. 

THANK YOU AGAIN TO GREG FOR HIS GENEROSITY IN SHARING HIS KNOWLEDGE AND INSIGHT WITH THE YOGA COMMUNITY. I HOPE YOU FOUND THIS INTERVIEW INFORMATIVE AND HELPFUL FOR YOUR YOGA PRACTICE & TEACHING! -JENNI

Learn much more from Greg Lehman on his website here, and follow him on Twitter!


Expert Q&A On Yoga & Breathing Misconceptions, Part 2 of 2

Welcome to Part 2 of my interview with Rich Severin, PT, DPT, PhD(c), CCS on yoga and breathing misconceptions! As you might remember from last week, I recently reached out to Rich because I had accumulated a number of questions regarding claims about breathing that I commonly hear in the yoga world that seemed questionable to me. As a physical therapist and board certified cardiovascular and pulmonary clinical specialist, I knew that Rich would have an extremely informed perspective from which to address my questions. (Please see Rich's full bio included at the end of this piece!)

Today I present to you the much-anticipated second half of our Q&A. Between these two installments, I feel that this is a very valuable and fascinating offering for yoga teachers who are interested in becoming more evidence-based in their teaching. I hope that you enjoy, and don't hesitate to share your comments and thoughts below!

 

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YOGA & BREATHING Q&A WITH RICH SEVERIN PT, DPT, PHD(C), CCS - PART 2 OF 2

 

QUESTION 4: Is there an alignment relationship between the rib cage and the pelvis (or between the diaphragm and the pelvic floor) that ensures optimal physiological function in the body? We often hear in the yoga & movement worlds that it’s important that the diaphragm be "stacked above" the pelvic floor so that these two structures can move in concert during breathing. If the rib cage and pelvis are habitually aligned in such a way that these two structures are not “stacked”, can this result in pain (especially around the spine and pelvis) and/or dysfunction in the body?

ANSWER: Everyone’s anatomy is unique. Everyone’s anatomy is slightly asymmetrical. Everyone’s. Our bodies respond and make adaptations to stresses over time as well. The ability to respond and adapt/remodel while preserving physiological function is how we’ve survived as a species for thousands of years.

The ability to respond and adapt/remodel while preserving physiological function is how we’ve survived as a species for thousands of years.
— Rich Severin

Now that’s not to say that sudden or gross changes to posture can’t result in problems. It can and most of that has to do with exposing the body to stresses and loads exceeding its capacity or without enough time to make adaptions. It’s also not to say that just because someone has a slight deviation from our socially constructed (and not biologically constructed) ideal posture they will have pain or dysfunction. So no I’m not certain that I would agree with that statement or line of thinking.

 

QUESTION 5: Is there a known causal relationship between specific patterns of breathing (for example habitual “belly breathing”) and specific core conditions such as pelvic organ prolapse and diastasis recti?

ANSWER: Like I mentioned above there’s a lot of things that go into disease and dysfunction. I wouldn’t ascribe one mechanism to any disease or dysfunction. There is some research suggesting that individuals with COPD might have a higher risk for urinary incontinence and pelvic floor dysfunction but that’s at the extremes of respiratory muscle dysfunction. I don’t think most people in yoga are at that level of disease. However if one were to bear down long enough and they had pelvic floor weakness/laxity I could reasonably see a prolapse develop. However even in that example it’s not a one to one relationship. I would caution against making that sort of relationship. 

 

QUESTION 6: In yoga class, we are always taught to breathe in and out through our nose rather than through our mouth. I can see how cultivating nasal breathing during yoga might slow the breath down and could therefore offer a meditative benefit to one’s practice. But are there significant physiological benefits to breathing through the nose instead of the mouth in a yoga practice - and in daily life in general?

ANSWER: Most people will generally breathe through their nose. Even those who use their mouth to breathe often still breath through their nose too. Nasal breathing is reflexive and as long as nasal airway resistance doesn’t get too high (like when you have a cold or congested nose), the lips maintain their seal and the tongue maintains contact with the back of the mouth cavity, you will breathe through your nose. Nasal breathing is innate and it allows us to warm, humidify and clean the air we breathe before it gets down to our lungs.

Nasal breathing is innate and it allows us to warm, humidify and clean the air we breathe before it gets down to our lungs.
— Rich Severin

The research is a bit limited and conflicting regarding whether mouth breathing or nasal only breathing is more efficient. Some studies demonstrate that nasal breathing is more energy efficient during exercise, however some have shown that there is no difference. Oral breathing definitely tends to dehydrate your oral passages and could make talking more challenging. 

 

QUESTION 7: If someone desired to change their habitual way of breathing (i.e. breathe more into their rib cage and less into their abdomen, for example), how easily can she/he re-set the way that their autonomic nervous system controls their ~20,000 breaths per day?

ANSWER: There’s a lot to unpack in this question. Without diving into too much respiratory physiology, the cadence and depth (pattern) of your breathing is automatically controlled by the respiratory control center in your brain stem. The pattern of breathing can be modified by various sensory inputs to activate different neural circuits of the respiratory control center to modify the pattern to match the stress, activity or condition the body is undergoing. The most notable and potent sensory input is the pH of your blood and concentration of carbon dioxide (CO2) which are monitored by nerves called chemoreceptors. When pH or CO2 gets too high or too low, breathing cadence and depth will respond instantaneously in order to maintain a cellular environment conducive to metabolic work to keep us alive. The body is incredibly efficient and effective at this process, and control of pH will always “win”. 

...the evidence that exists now does not suggest that we can change our pattern of breathing permanently due to the role breathing takes to keep us alive.
— Rich Severin

We can make temporary volitional changes to our breathing pattern. We can even temporarily stop breathing. However as I mentioned above the control of pH will always win. So while we can absolutely make these changes temporarily, the evidence that exists now does not suggest that we can change our pattern of breathing permanently due to the role breathing takes to keep us alive.

What many people might observe is that when one is stressed or in pain it usually results in hyperventilating or rapid breathing. This is due to our respiratory control center responding to the sensory and emotional inputs and thus selecting an according breathing pattern to match this “perceived threat”. By practicing slow breathing it may allow one to achieve a more relaxed state or distract themselves from pain or stress. If this relaxed state is achieved, the sensory input of a perceived threat has been absolved and different circuitry in the respiratory control center will be activated producing a more relaxed pattern of breathing. We’re finding that some of the circuitry used or involved in these breathing “programs” utilized might be hardwired. 

 

QUESTION 8: The term “breathing dysfunction” is a commonly-used label in the yoga & movement worlds these days. Do yoga and movement teachers with no concurrent medical training have the authority and expertise to identify and label breathing dysfunctions and disorders?

ANSWER: Breathing dysfunction is a bit of a nebulous term. We encounter this issue often in physical therapy practice too. Unfortunately this term is often used cavalierly and done without performing a reliable, valid and objective assessment of breathing performance such as spirometry (lung volumes), respiratory muscle performance, pulse oximetry or arterial blood gases, and markers of ventilatory efficiency during exercise.

Visual inspection and manual assessment of breathing function are very subjective and are not sufficient to determine if someone’s breathing is dysfunctional.
— Rich Severin

Visual inspection and manual assessment of breathing function are very subjective and are not sufficient to determine if someone’s breathing is dysfunctional. So unless those objective measures mentioned previously are being used I would strongly caution against labeling anyone’s breathing as dysfunctional; especially if they are walking and talking into your clinic or studio. Remember there are so many things involved with breathing and we generally do a pretty good job at it.

 

THANK YOU AGAIN TO RICH FOR HIS GENEROSITY IN SHARING HIS KNOWLEDGE AND INSIGHT WITH THE YOGA COMMUNITY. I HOPE YOU FOUND THIS INTERVIEW INFORMATIVE AND HELPFUL FOR YOUR YOGA PRACTICE & TEACHING! -JENNI


Rich Severin PT, DPT, PhD(c), CCS is a physical therapist and board certified cardiovascular and pulmonary clinical specialist. Currently he serves on faculty as a Clinical Assistant Professor at Baylor University in the Hybrid Doctor of Physical Therapy program and The University of Illinois at Chicago (UIC) Department of Physical Therapy as a Visiting Clinical Instructor. At UIC he also serves as the program coordinator for the Bariatric surgery rehabilitation program and is working on a PhD in rehabilitation science with a focus on cardio-respiratory physiology and obesity.  He earned his Doctor of Physical Therapy Degree from the University of Miami. He completed a cardiopulmonary residency at the William S Middleton VA Medical Center/University of Wisconsin-Madison and an orthopedic residency with a focus on clinical research at the UIC. He has made scholarly contributions and presented both nationally and internationally on topics relating to cardio-respiratory physiology and clinical practice. He is an active member of the America Physical Therapy Association (APTA), The American Physiological Society and several other professional and scientific societies. He serves on the board of directors for Cardiopulmonary Section of the APTA as the chair of the communications committee and as a member of the nominating committee. Dr. Severin is also a member of the APTA Cardiopulmonary Section Heart Failure Clinical Practice Guideline development team, the Specialization Academy of Content Experts, and the editorial board for Cardiopulmonary Physical Therapy Journal. Follow him on twitter @PTReviewer.

[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!

Are Some Movements Inherently Bad?

We are often taught that there are ways the body can move that are inherently bad for us. We’re told that these movements will cause damage, “wear and tear”, or imbalance in the body, which will inevitably lead to pain and discomfort. Some examples of movements like these are cervical spine flexion (e.g. "text neck"), lumbar spine flexion, and many classic yoga alignment taboos like placing the foot directly on the knee in tree pose (vrksasana).

While this perspective is certainly well-meaning, it is missing some key insights about the body that recent science has revealed to us. Instead of asking whether a movement is good or bad, a more nuanced and helpful question is: are one’s tissues adapted to withstand the load of a particular movement? When we approach movement from this perspective, it becomes clear that there are no inherently bad movements - there are simply movements whose loads our bodies are not currently adapted to handle.

 


OUTDATED MODEL OF PAIN

One reason that the "bad movements" belief is unhelpful is that it is based on an outdated model of how pain works. If you read my recent article on The New Science of Pain in Yoga International, you may be familiar with the fact that the link between pain and actual tissue damage is often very weak. Recent studies have repeatedly shown that many people have real tissue damage in their bodies and no associated pain, and conversely, many people who experience chronic pain in their bodies have no associated tissue damage at all. Additionally, pain is not an input to the brain from the periphery of the body (i.e. from tissue damage), but an output from the brain that is meant to signal us to take some sort of protective action.

There are many more implications that the new science of pain has for today’s topic of “bad movements”, but for the sake of time I’m going to to leave this part of the discussion at that and encourage you to read my original article about pain if these ideas are new to you. (This paradigm shift is fascinating and important for us yoga and movement teachers to understand!)

 


DO OUR PARTS WEAR OUT LIKE THE TIRES ON A CAR?

The second main issue with the “bad movement” approach is that it is based on a model that views the body as similar to a car, or a machine. In this model, if we move or align our body in sub-optimal ways over time, certain body parts will wear out before others due to the accumulation of microdamage. Just like a car’s tires might wear out unevenly and need premature replacing if they aren’t aligned properly, our body’s joints (think knees, hips, spinal joints) can wear out if we move or align them poorly.

This idea makes great intuitive sense, but there is an important distinction between cars and human bodies that is missing from this perspective. Unlike a car or a machine, whose parts do mechanically wear out with time, our body consists of living, biological tissues which are constantly turning over and remodeling according to the demands they experience. For example, we all know that if we load our muscles and connective tissues with a weight-training program at the gym, they will respond by becoming stronger in order to handle these loads. Another way of saying this is that the tissues of our body adapt to the stresses placed on them (also known as Davis’ Law).


TEXT-NECK AND TISSUE ADAPTATION

Text-neck is not an inherently damaging movement.

Text-neck is not an inherently damaging movement.

As counterintuitive as it may seem, this same principle of adaptation applies in the case of the traditionally-labelled bad movement of “text-neck”. We are often cautioned that our head weighs the approximate amount of a bowling ball, and for every inch forward that it creeps, our neck is burdened with 10 additional pounds of damaging weight, leading to inevitable pain and imbalance in this area. (I have warned my yoga students about the dangers of text neck myself in the past too - believe me!)

But such cautions are rooted in the model which views our body like a machine full of parts that will wear out and break down if poorly aligned. By contrast, the living, biological organism of our body is constantly adapting to the loads it experiences. Therefore, if you position your head slightly forward of your torso on a regular basis, the muscles, fascia, and connective tissue of your neck will naturally adapt to become stronger and better able to withstand this load.

Now it’s certainly the case that holding any position for a long period of time, be it text-neck or otherwise, is problematic. But simply flexing our neck forward to look down is a natural movement that our body is designed to do. As well-intentioned as the cautions against text-neck are, they are not truly science-based and can encourage unnecessary fear and worry around this movement (which, ironically, can contribute to pain!)

 


“BAD ALIGNMENT” IN TREE POSE

Yoga alignment rules are another realm where "bad movement" beliefs often come into play. One classic example is the instruction that nearly every yoga student has heard to never place the foot on the opposite knee in tree pose (vrksasana). The reasoning behind this alignment rule is that the laterally-oriented force that the foot applies can damage the knee joint. We are instead instructed to always place our foot either above the knee (on the thigh) or below the knee (on the shin).

This alignment taboo does make intuitive sense, but let’s use the lens of biomechanics to look a bit closer. First of all, as we discussed above, the tissues of the body adapt to the loads placed on them. Therefore, in theory, if someone were to practice tree pose with their foot on their knee frequently enough, the tissues of the knee should adapt and get stronger to handle that load.

Secondly, yoga teachers often cue their students to actively press the standing leg and tree leg foot into one another in this pose. If practiced this way, this action actually creates stability in the standing knee joint which should resist any pressure applied by the tree leg foot.

And lastly, tree pose can be practiced with the tree leg actively working to hold itself up, rather than passively leaning against the standing leg. (Picture the leg lifting itself, rotating, and placing the foot on the opposite leg all on its own, without the help of your hand, and then holding itself up there.) In this scenario, the tree leg’s foot would actually be placing no pressure on the standing knee at all.

Upon closer examination, it becomes clear that the classic teaching that foot-on-knee placement in tree pose is inherently “bad alignment” is a questionable belief that probably does not apply to most bodies in this pose.

 


HEADSTAND (SIRSANA)

Another controversial asana in the yoga community is headstand (sirsana), a movement that many wonderful and well-meaning yoga teachers believe should never be practiced because our cervical spine is simply not designed to carry the full weight of our body in such a fashion.

It is absolutely the case that most Western bodies are not adapted to handle the loads that headstand places on their cervical spine. (This is why teaching full headstand to a group class is definitely not advisable!)

But if we look at headstand as a movement that applies certain loads to the body, and if we understand that the tissues of our body adapt to the loads they experience, we begin to realize that if someone were to intelligently and progressively load their cervical spine over time (and it would need to be slowly and over a lot of time!), it would be possible for their body to adapt to the loads of headstand. Sirsana would be a safe asana for this body to practice. It's therefore an oversimplification to state that headstand is an inherently bad movement. It would be more accurate to say that it is simply a movement which many bodies are not currently adapted to handle (but they could be trained with time!)

 

CONCLUSION

When we start thinking about movement in terms of load instead of inherently “good” or “bad”, we gain a more nuanced perspective on the body. It’s true that any movement with high enough loads can injure us, but low load positions that we frequent regularly are unlikely to be the source of damage and pain in our body because our tissues will respond by adapting to handle them. These realizations lead us away from viewing our body as an innately fragile structure that is vulnerable to damage from suboptimal forces, and instead as the strong, resilient, and adaptable organism that it truly is.

Does Traditional Yoga Lead to Muscular Imbalance? (Part 2)

Part 2 of my Yoga International article on yoga's strength imbalance was published today! I'm lucky to have been able to reference the work of several of my amazing teachers in this piece. I'm also more than grateful to Yoga International for embracing and sharing the positive message that while yoga is a fantastic practice for us, it isn't a "complete" one from an anatomical perspective, and there are a lot of other great movements out there that we can do to round things out. I hope you enjoy!

Does Traditional Yoga Lead to Muscular Imbalance? (Part 1)

I am MORE than excited about my new article in Yoga International that was just published today! Whoo-hoooo! It's Part 1 of a 2-part series and I really like how Yoga International summed it up:

"Yoga is often described as a balanced and complete long-term health and wellness practice. But does a consistent yoga practice really provide the body with everything it needs to function optimally? Yoga teacher Jenni Rawlings explains that although asana is a wonderful and transformative practice, when explored through the lens of anatomy, there is one aspect of this practice that is surprisingly unbalanced. But don't fear! In this article, she'll not only elucidate what this imbalance is but also how practitioners can undo it. Take what you learn and enhance the safety and overall function of your practice today!"

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: 5 Weeks to Strong, Flexible Hamstrings online program

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

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!