As yoga gained popularity in the West throughout the 20th century, its main draw consisted of physical perks like coordination, muscle tone, and flexibility. In recent years, however, more people have embraced the practice for its impact on mental well-being. It’s now widely accepted and scientifically supported that yoga helps relieve stress, and research on this topic continues to grow. The physiological explanation for yoga’s positive effect on stress comes down to one major component: the nervous system.
The 2022 survey by Yoga Alliance, Yoga In the World, examined why people choose to start practicing yoga. Results showed that 51% of people in the U.S. cite stress relief as their primary intention for beginning a yoga practice, replacing previous goals like flexibility.
As a yoga teacher, I greatly value understanding the “why” and “how” of the practices we choose to do on our mats. For me, appreciating yoga’s effectiveness at combatting stress begins with examining the intricacies of the human body and the vital operations of the nervous system. Once we grasp what’s going on internally, we can choose specific practices that suit our needs and support us in holistic well-being.
If you’ve been curious about yoga as a tool for stress relief and nervous system balance, stick with me here as we dive deep into the science and explore specific yoga techniques to promote equilibrium in the nervous system.
Get to Know Your Nervous System
To provide a simple analogy, think of your nervous system like the wiring of a house. It sends signals or information along pathways to enable control and communication between different areas of the body. The nervous system is responsible for sensory perception, motor control, and integrating information.
Parts of the Nervous System
To understand yoga’s therapeutic effects on holistic well-being, it’s helpful to understand the specific parts of the nervous system affected by our practice. Let’s break it down:
- The two main branches of the nervous system are the central and peripheral nervous systems.
- Within the peripheral nervous system are the somatic and autonomic nervous systems.
- The autonomic nervous system encompasses the sympathetic, parasympathetic, and enteric nervous systems.
Yoga targets the autonomic nervous system, which controls all the automatic processes your body unconsciously performs to survive. It also plays a significant role in how we respond to stress.
The sympathetic nervous system activates our “fight or flight” response to stressful situations, raising blood pressure and heart rate, increasing respiration, and pausing digestion. By contrast, the parasympathetic nervous system initiates our “rest and digest” mode to slow heart rate and respiration, lower blood pressure, and restart the digestive process.
Regarding the effects of yoga on the nervous system, we focus primarily on this latter parasympathetic component and, more specifically, the all-important vagus nerve, which makes up 75% of the parasympathetic nervous system.
Vagus Nerve Importance and Function
The vagus nerve is a cranial nerve that extends from the brainstem into the abdomen, with various branches connecting to organs and tissues throughout the body. Its name reflects its extensive reach throughout the body, as vagus means “wandering” in Latin.
The vagus nerve regulates numerous vital bodily functions. Here are a few of its most essential functions:
- Communicates information from the brain to the digestive system and vice versa
- Controls inflammation related to immune response
- Regulates blood pressure, heart rate, and human respiratory functions
- Controls muscle contraction throughout the digestive tract (peristalsis)
- Manages secretions of enzymes and acids and tension receptors in the stomach
- Controls the muscles in the larynx and pharynx that are responsible for swallowing and voice production
Vagal tone is a term you might have heard recently within the wellness community. It indicates the vagus nerve’s function level, measuring your body’s ability to handle stress and maintain balance.
So, when you’re experiencing stress, and your breath gets shallow, your heart beats faster, and your stomach feels clenched or upset, it all returns to the vagus nerve. On the other hand, for all your body’s systems to function correctly, you must maintain a proper vagal tone.
Yoga as a Stress-Relief Tool
When we talk about feeling “stressed out” or “anxious,” we’re referring to the physiological and psychological response to perceived threats or challenges. Our nervous system initiates this response when it senses we’re in danger.
Evolutionarily, this mechanism helped us stay alive. But these days, stress and anxiety often cause us more harm than good.
- When unmanaged, stress can contribute to chronic illness and create a risk for mental health challenges.
- Anxiety disorders affect nearly 20% of the U.S. population, while more than 30% of adults reported experiencing symptoms of anxiety at some point in the past year.
Our nervous systems are in overdrive. While yoga is not a cure for a diagnosed anxiety disorder, it can offer significant relief from symptoms of anxiety and stress, as evidenced by a growing body of scientific research related to nervous system activity.
- This review of existing studies found preliminary evidence that yoga helps regulate the sympathetic nervous system and adrenal activity based on measuring heart rate, cortisol levels, and blood pressure.
- This study measured salivary stress hormones before and immediately after 60 and 120 minutes after a yoga session. The ratio of hormones in saliva indicated increased parasympathetic nerve activity up to 120 minutes after yogic stretching.
- Another study showed that yoga can restore balance to the nervous system by bringing the parasympathetic nervous system into prominence by stimulating the vagus nerve to correct under-activity.
- Yet another review of current research examined factors like oxygen consumption and heart rate and concluded that yoga effectively increases parasympathetic nervous system activity, resulting in a more regulated heart rate and reducing wear and tear on the body caused by chronic stress.
So, next time you come out of Savasana at the end of a yoga class and notice a grounded and calm feeling, it’s not some magic yoga trick – it’s your parasympathetic nervous system doing its job!
Stimulating the Vagus Nerve
It’s important to note that not all styles of yoga produce the same immediate effect. For example, if you need anxiety relief and increased parasympathetic activity, opt for a gentle or restorative practice rather than a Power Yoga flow, which aims to pump up your heart rate.
Of course, all yoga benefits your body and mind in various ways. But there are specific practices you can focus on if you’re interested in increasing vagal tone. In my own experience with managing anxiety with asanas, incorporating these techniques into my yoga routine has helped me immensely.
Vagus Nerve Yoga Poses
- Sit in a chair or on the floor in an easy cross-legged position.
- Tilt your head, dropping your right ear toward your right shoulder.
- Reach your right arm across your body and place your right hand on your left shoulder.
- Hold the stretch for 3 to 5 deep breaths, then lower your hand and lift your head.
- Repeat the stretch on your other side, dropping your left ear toward your left shoulder.
Why this works: The vagus nerve passes behind the sternocleidomastoid muscle in the neck. Stretching the neck muscles combined with taking deep breaths stimulates the vagus nerve.
- Begin on your yoga mat kneeling: sit your hips back onto your heels with your toes untucked and the tops of your feet on the floor.
- Keep your big toes together and separate your knees.
- Reach your arms forward and bring your forehead down to the floor.
- Focus on taking slow, deep breaths. Hold the pose for 5 to 10 breaths, then walk your hands toward you to sit up.
Why this works: This restorative position encourages deep breathing and gently compresses the abdomen, stimulating the vagus nerve.
Gentle Heart Openers
Heart openers like Cow, Cobra, or Supported Fish Pose are some of my go-to poses when I’m stressed. Try Cobra Pose and see how you feel:
- Begin on your mat in a prone position, lying on your stomach. Extend your legs behind you with your feet slightly separated and the tops of your feet on the floor.
- Place your hands underneath your shoulders.
- As you inhale, lift your head and chest off of the floor. Keep your elbows slightly bent and close to your body.
- Reach the crown of your head forward and up, maintaining length in your spine. Keep space between your shoulders and ears, keeping the neck long.
- Gaze straight ahead and hold Cobra Pose for 3 to 5 breaths, then lower gently and rest for a couple of breaths.
- Repeat two more rounds of Cobra as you are able.
Why this works: The vagus nerve is connected to the cardiovascular and digestive systems. Gentle backbends encourage blood circulation and release tension, allowing you to take deeper breaths.
There are many twisting yoga asanas, but my favorite is the classic Supine Twist.
- Lie on your back with your body completely relaxed.
- Bring your right knee in towards your chest and squeeze it toward you.
- With an exhale, twist and take your right knee across your body to the left as your right arm reaches in the opposite direction.
- Stay in your twist for 5 to 10 breaths, letting your body release tension with each exhale.
- Return gently to your back and release your right leg down when ready.
- Rest in Savasana for a couple of breaths, then repeat Supine Twist on your other side, using your left leg.
Why this works: Twists compress and release abdominal organs, stimulating the vagus nerve, which has branches that connect to the digestive system.
There’s a reason why we typically end yoga classes with Savasana: it gives the body time to shift into parasympathetic activity.
- Lie on your back with your entire body relaxed.
- Separate your legs slightly and let your feet fall open naturally.
- Bring your arms by the sides of your body, palms facing up.
- Focus on breathing deeply. Draw your inhales down into your belly and keep your exhales long and smooth.
- Give yourself at least 10 minutes in Savasana to relax fully.
Why this works: when the body is fully relaxed in Corpse Pose, the nervous system signals to reduce stress hormones, shifting from “fight or flight” into “rest and digest” mode.
A well-rounded yoga practice includes more than physical asanas or poses. Pranayama breath control practices are integral to traditional yoga classes. In general, slow and diaphragmatic breathing enhances parasympathetic nervous system activity.
You can also try these classic breathwork techniques to stimulate your vagus nerve. For each practice, begin comfortably seated with your back straight and shoulders relaxed. Allow your breath to flow naturally for a few minutes to calm your mind and prepare for the practice.
Kumbhaka (Breath Retention)
- Inhale through your nose, feeling your torso expand as your lungs fill with air.
- Pause and retain your breath at the top of your inhale as you silently count to 3.
- Then, release your breath smoothly, exhaling completely.
- Repeat this pattern for at least one minute, then allow your breath to return to its typical pattern.
Bhramari (Bumble Bee Breath)
This form of pranayama combines deep breathing with a soft vocalization to stimulate the vagus nerve.
- Keep your mouth closed and jaw relaxed. Separate your teeth slightly and bring the tip of your tongue behind your upper front teeth.
- Inhale deeply through your nose.
- As you exhale through your nose, make a low-pitched “hmmm” sound from the back of your throat, like a bee’s hum.
- Repeat this cycle 3 to 5 times, focusing on keeping the sound of your hum steady and soft.
Have you ever chanted “om” at the end of a yoga class? Humming and singing activate the muscles in the larynx, creating vibrations that stimulate the vagus nerve. Practice your favorite mantra, chanting a few rounds at the end of your yoga session to increase your vagal tone.
If mantra chanting is new to you, start with a few repetitions of Om, the simplest of all.
- From a comfortable seat, inhale deeply through your nose.
- With your exhale, open your mouth and chant Om as “A-U-M,” starting with an open A sound, transitioning to U, then closing your mouth and ending on M.
- Repeat this cycle twice more at your own pace, following your breath.
- Focus on the resonance and vibrational sounds within your body. After your third Om, allow your breath to flow naturally for another minute.
You don’t have to be on your yoga mat to use some of these methods! Try a few neck stretches at your desk after a tense work meeting, or hum a few Bumble Bee Breaths when stuck in traffic.
Understanding the physiological effects of yoga helps us use the practice more effectively to meet our needs, bringing balance to the areas of our lives that require more attention – like stress management.
The next time you find yourself altered by a stressful situation, bring mindful attention to your body and notice your nervous system at work. Then, use the techniques explained here to create an intentional shift from sympathetic to parasympathetic action.
By weaving these specific practices into your yoga routine, you’re actively helping your nervous system restore equilibrium and creating a stronger mind-body connection, which feels pretty empowering! Instead of descending into a spiral of anxiety, your yoga practice can guide you toward a calmer and more grounded state.
If you’re a yoga teacher or a yoga teacher in training, introducing practices that stimulate the vagus nerve into your classes can be an effective and simple way to take a trauma-informed approach to teaching yoga.
Some people like to talk about the so-called “transformational power” of yoga – but it turns out to be true! Throughout yoga’s rich history, it has been a tool for practitioners to maintain physical and mental well-being and access inner peace. Through applying modern knowledge of our body’s interconnected systems, we can better appreciate yoga’s potential to improve our lives.