by Jenni Rawlings
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.
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 gomukhasana 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 eka pada sirsasana, 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 gomukhasana, 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.
~
Jenni Rawlings loves to weave her natural interest in anatomy and biomechanics into her yoga teaching. She is grateful to so many teachers who inspire her, most notably amazing biomechanist Katy Bowman. You can find out more about Jenni at www.jennirawlings.com.
—
See PART 1 here: Stretching Is In Your Brain: A New Paradigm of Flexibility and Yoga (PART 1)
——
Earlier…
A minor quibble: many of us who are not particularly flexible can put our foot comfortably behind our head from lunge without any assistance. It follows using our hands to get into effectively the same position does no harm.
A couple of more major issues. What is the point? Passive flexibility frequently goes before active, making it possible. Passive shoulder stretching makes it possible to actively open the shoulders in handstand, for example. Momentum – many people can’t hold their foot head high but can swing it that height with startling effect on the person it connects with. Speed – many of us have found we can move faster through the range of motion required for a movement if we have passive flexibility beyond that range. Ease – like speed. Then there’s the therapeutic benefit of passive stretching. While we all know that our muscles don’t get “tight” in a simplistic sense, or “longer” when we stretch many of is also know that increasing our range of movement by passive stretching is a way to heal various aches and pains brought on by more active movements
If yoga was just about stretching or strength or just physical….maybe…..I think that the whole picture of yoga is missed here. Maybe the point is not just to get into the pose safely…maybe the point for getting into the pose has to do with all the stuff you go through mentally and energetically on the way.
I loved this article, and think it hits on so many great points. I’ve also been doing a fair bit of research on the nervous system and the way in which it governs movements of all kinds – from gross muscular to subtle messages and emotions – and I think this article explains this dynamic fantastically. To the comments above, John – I don’t think she was talking about passive stretching being a problem, but rather forceful movement of limbs into deep stretches. Especially for those of us who have hypermobility issues, this can be really dangerous. And while I agree with Shanna, that yoga is much (MUCH) more than stretching, so many people are ending up with soft tissue injuries from yoga that teachers do need to look at how they’re teaching asana. Plus, I think that this perspective gives a whole new dimension to teaching the postures – to really listen for those subtle signals from the connective tissue and muscles and presents a new way to figure out what a limit is in the body. Well done.
Nice post! I liked your illustrating how to approach hanumanasana from a strong and integrated path.
You may really enjoy Dr. Doige’s new book, The Brain’s Way of Healing. It is very readable, and talk about how neuroscience is rapidly changing. These new ideas are rewriting how me can heal and improve our physical reality- and how (as yogis ahve known for centuries) that changes everything.
If you like Katy Bowman, and want to look deeper into the possibilities of human movement, I’ll suggest you try Feldenkrais. Katy is great, and she makes nice corrections that are easy to follow. Feldenkrais is perhaps more challenging to understand, but the richness is infinite. Depth and diversity have their rewards. There are thousands of us contributing to developing this work. Many of us are yogi, martial artists, dancers, musicians, etc. We’d love to have more people of passion and intelligence. Please take a look!
I am so grateful to have come across Part 1 and Part 2 of this article. I love how you introduced the nervous system previously and how that affects how our body moves and then elaborated on it in this part! So very helpful and I feel like I learned a lot just reading these two parts.
very nice tips for my next yoga session, I definitely enjoyed this post, I also have a blog, i would love if you check it out, I would apreciate your feedback 😀
https://www.facebook.com/pages/Essential-Energizer/1047532571942566?fref=ts
It’s all correct, but let me be a nit-picker: flexibility is *not* in the brain. Nervous system does not equal the brain. The neurons regulating flexibility are actually short-circuited through the spinal cord.