SNS vs. PNS: what does your nervous system have to do with your yoga practice?

turns out, a lot.

if you’ve ever wondered why yogis are stereotyped as super zen, it’s time you learn the science that makes that stereotype pretty accurate.

everyone has a nervous system, which is broken down into different branches based on function. For the purpose of discussing the relationship between yogic practices — to include movement, breath work, meditation, and attitude — and the nervous system, we are focusing on the Autonomic Nervous System (ANS).

The ANS is the branch of your nervous system that operates unconsciously, meaning it is functional whether you get involved or not. The ANS is reactive to our environment, and manages our internal functioning. It can be broken down into three subcategories:

  1. Sympathetic Nervous System (SNS)

  2. Parasympathetic Nervous System (PNS)

  3. Enteric Nervous System (which we won’t be diving into here today)

Let’s break these down even further before connecting the dots between yoga and the SNS/PNS.

The SNS can be thought of as the branch of your nervous system responsible for “fight, flight, or freeze”. When activated, the SNS restricts blood flow from organs of digestion and even from the brain, and instead allocates that blood to the limbs, readying the body for a fight or to run away quickly. Addiontally, when SNS is active the body releases stress hormones (i.e. cortisol), your heart rate increases, and your breath quickens.

Then there is the PNS, which can be thought of as the branch of your nervous system responsible for “rest and digest”. When the PNS is activated, blood flow is plentiful in the “trunk organs” including the digestive organs, the heart rate lowers, and the breath is slows and deepens.

Hundreds of years ago, your SNS would be activated in life threatening situations such as being approached by a lion while out hunting for food. The interesting thing is, you have the same nervous system response today to watching a graphic show or getting in a fight with your best friend. Think through your typical day, full of social interactions, work stressors, traffic, long lines at the grocery store and the coffee shop, missed flights, sinks full of dishes, flat tires, sick children, dogs wildly barking, mail from the IRS, on and on and on. Your body doesn’t discriminate against stressors, and so the reaction is the same whether you’re face-to-face with a lion or sitting on your couch watching an intense fight scene on Game of Thrones.

Just reading that list of stressors is stressful! We need tools to stay in control of our body as we navigate the world we live in. That is where yoga comes in.

The quickest, easiest, cheapest, most accessible way to access your SNS or PNS is through your breath. That is why we launched Yoga to Cope with just breath tutorials and meditations, not asana tutorials. “Change your breath, change your life” is a great quote, sure, but the best thing about it is that its TRUE.

Your breath is your direct connection to your nervous system. If you are feeling anxious and need to calm down, there is a breath practice for that. Take a full, smooth breath in, and make your exhale twice as long a your inhale. If you’re feeling depressed and need a breath that will invigorate and enliven you, try flipping that by taking a long, smooth inhale followed by an exhale that is half as long.

The breath is a powerful thing. It is the base of you as a living being, and the base of any balanced yoga practice. There are many free, downloadable breath meditations available here for you to try!

Your body doesn’t discriminate against stressors, and so the reaction is the same whether you’re face-to-face with a lion or sitting on your couch watching an intense fight scene on Game of Thrones.

The brain and spinal cord are star players when it comes to your nervous system, as well as your sensory organs, including the skin. Your body is full of nerves, and these nerves are in in constant communication through an ongoing stream of information intake and signal output. When a bundle of nerves occurs in one place, it is called a nerve plexus. These plexuses are located along the back of the body/spine, from the perineal center to the midbrain, and are landmarks for where each of the principle bodily chakras are assigned. Chakras are a topic for another day, but this focus on the back body is very important. For simplicity as we move forward with this topic we will refer to this as “the spine”, though we acknowledge that Mooladhara Charka, the root chakra located in the perineal center, is not actually at/on the spine.

If so many nerve plexuses, six to be exact, occur along the spine, and nerves control how calm or not calm you are, it should come as no surprise that many breath techniques and asanas focus on and relate to the spine. Asana is an often highlighted aspect of a yoga practice. Did you know that each category of asana relates to a specific energetic effect that is defined by how the spine is moving?

That’s right, forward folds activate your PNS, while backbends active your SNS. Imagine how useful this information could be for someone suffering with depression or anxiety!

If a person is feeling depressed, and is spending a lot of time in happy baby and child’s pose without proper counter-posing, they’re likely just taking themselves deeper into the ground.

If a person is experiencing anxiety and regularly attends a fast-paced vinyasa-style class with lots of chatturanga and wheel pose variations, they are only winding their spring even tighter.

Exhaustion is not relaxation.
Exhaustion is not relaxation.
Exhaustion is not relaxation.

This is important.
We tend to gravitate to what we want, but an important question to always be asking yourself is what do you NEED?

We tend to gravitate to what we want, but an important question to always be asking yourself is what do you NEED?

Use this basic knowledge of your nervous system to build or continue a practice that suits where you are and what you need right now, today. Tomorrow, next week, five years from now you may need something different. Be in control of your needs and how to meet them. Choose to meet yourself where you are with honesty and openness.

If you’re feeling down, sad, depressed, or introverted to an extreme, try practicing some accessible backbends and invigorating inversions (i.e. baby cobra, bridge pose, sphinx, downward dog, and locust)

If you’re feeling anxious, jittery, nervous, or generally all-the-way-up, try practicing some calming, grounding forward folds (i.e. child’s pose, happy baby, standing forward fold with bent knees, and sleeping pigeon)


Counter-posing is important to understand as well. A practice full of nothing but backbends may take someone over the line of balance and into a state of anxiety. Yoga is all about balance, so work to find yours by building your own practice with a variety of poses, spending more time in the ones that activate the aspect of your nervous system you need to tap into. If you’re going to studio or gym classes, take notice of the poses you’re being taught. Ask yourself, does this class meet me where I need to be met energetically?

If you need more guidance, it’s always a good idea to speak to your yoga instructor or find a private coach who can help guide you. Additionally, there are many resources available to you online, here at Yoga to Cope and otherwise.

photography by Victoria Wall Harris

photography by Victoria Wall Harris