A few weeks ago I introduced you to the vagus nerve, that fascinating wandering nerve responsible for our calming ‘rest and digest’ and ‘tend and befriend’ responses as well as being a communication channel between body and mind. Read on to find out about the signs of a weak or strong vagus nerve and how make this nerve as healthy as possible to keep us happy and resilient in the face of life’s stresses.
How do we know if the vagus nerve is strong and why does it matter?
The strength of the vagus nerve is known as ‘vagal tone’. There is naturally a slight increase of heart rate each time you inhale and a slight decrease of heart rate when you exhale. The variation between the two is a marker of vagal tone – the larger the difference the stronger the vagus nerve. There are also some key indicators of mental, emotional and physical health that go hand in hand with high or low vagal tone.
High vagal tone is associated with:
- Mental health and emotional resilience – the ability to recover quickly from shocks and acute stress
- Cardiac and respiratory health
- Strong immune system
- Good memory
- Capacity to build friendships
In contrast, low vagal tone is associated with:
- Depression, anxiety and post-traumatic stress disorder
- Autoimmune diseases, chronic pain and inflammatory illnesses
- Stroke and heart attacks
In modern life, where many of us experience a persistent level of stress and overwhelm, the ‘fight or flight’ response can become the default mode of being, while the calming parasympathetic nervous system takes a back seat. This persistent state of ‘fight or flight’ can be both a symptom and a cause of low vagal tone, and makes people susceptible to physical and mental health problems.
How to increase vagal tone for wellbeing and resilience
In the field of medicine, electrical devices are starting to be used to stimulate vagus nerve activity to treat conditions such as depression, chronic pain, epilepsy and inflammatory illnesses like rheumatoid arthritis. But there are several things we can all do to strengthen the vagus nerve naturally over time, by regularly encouraging its activity. You won’t be surprised to hear that yoga practices have a significant role to play here.
- Breath: the slow diaphragmatic breathing you’ve probably practiced in your yoga class stimulates the vagus nerve, as does the ujjayi breath (‘ocean breath’) which slightly constricts the back of the throat, lion breath which activates the facial muscles we use for smiling, and coherence breathing where chimes regulate your breath so the inhale and exhale are 6 seconds apart.
- Meditation: Loving Kindness meditation (also known as Metta meditation) is found to lead to an increase in vagal tone.
- Voice: Chanting ‘Om’ activates the vagus nerve and is more effective at doing so than chanting other sounds. Being among calm, engaging, soothing voices (like your yoga teacher’s voice perhaps) also activates the vagus nerve.
- Face: Splashing the face with cold water; relaxing with an eye pillow over the eyes to create very gentle pressure; smiling; yawning; and gargling all increase vagus nerve activity.
- Social connection: Interacting with others in a friendly, calm, and kind way activates the vagus nerve. Studies suggest there is an ‘upward spiral’ where positive social interactions stimulate vagus nerve activity and vice versa.
- Digestion: Cultivating healthy intestinal bacteria and eating nourishing food is another way of activating and strengthening the vagus nerve, and is thought to help people with anxiety or depression to regulate their emotions as a result.
It was a breakthrough moment for me when I first discovered that these practices not only help us feel calm in the moment (like taking deep breaths in a stressful situation), but that practising them consistently over time improves wellbeing in the long term through increasing vagal tone.
Yoga, stress and the vagus nerve
Yoga has always been about calming the mind (despite what you may have seen on social media!) and neuroscientific research is now beginning to explain what the ancient yogis knew intuitively to be true.
Breathing techniques (pranayama), chanting, meditation, compassion, and healthy eating all contribute to increasing vagal tone and are all aspects of Patanjali’s eight limbs of yoga. Research has also found that practising hatha yoga (asana/postures) is associated with increased vagal tone, and that other types of physical activity like walking don’t have the same effect. And stress-related disorders like depression, anxiety, epilepsy, post traumatic stress disorder and chronic pain (correlated with low vagal tone) have been shown to improve in response to yoga (with an associated increase in vagal tone and the neurotransmitters that improve mood).
Here are a few other ways yoga might help to increase vagal tone:
Mindfulness and re-training the nervous system: Yoga teaches us to be comfortable with discomfort, observing it rather than attaching to it. We place the body under some duress during our physical yoga practice but at the same time we breathe slowly and calmly, communicating via the vagus nerve to the brain that we are safe. Over time, this can discourage the nervous system from overreacting to stress and discomfort as if they were life-threatening situations, overriding the evolutionary stress response that triggers ‘fight or flight’ mode.
Moving with the breath: In yoga we tend to move with the breath in a way that reflects heart rate variability (the measure of vagal tone) – we activate on the inhale and soften on the exhale. In this way, we are making use of natural physiological patterns of activation and relaxation, while potentially also increasing vagal tone in the process.
Posture: Posture can influence how we feel emotionally, so the attention yoga places on healthy alignment in the body, keeps sending a message via the vagus nerve to the brain to say that all is safe. This is in contrast to the rounded position our bodies can take on through too much desk time – curling inwards is an evolutionary response to danger, which can keep the stress response active unnecessarily.
Ancient wisdom and modern neuroscience
Patanjali’s Yoga Sutras tell us “yoga is the cessation of the fluctuations of the mind”. The eight limbs of yoga help us to identify and release the thoughts and ideas we become attached to; to find calm self-acceptance and compassion for others; to realise that everything is one; and to realise that our true self resides in the stillness within us rather than in our external circumstances.
Whilst the ancient teachings of yoga present us with a spiritual practice towards enlightenment (Samadhi), neuroscientific research is showing us they are also powerful aspects of mental and physical health, emotional resilience, and happiness.
So remember each time you get on your yoga mat, you’re gradually strengthening your vagus nerve, bringing the calming side of your nervous system into balance with the activating side, and bridging the disconnect between body and mind that is a symptom of modern life. The practice of yoga is an investment in your wellbeing, helping you towards resilience and happiness. I find this knowledge to be a great motivating factor to help me be more consistent in my yoga practice, and I hope it helps you in some way too.
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Remember to check out the first post in this series on the vagus nerve if you haven’t already – it gives a good background to how the vagus nerve works.
This blog post is based on my elective research for my yoga teacher training in 2016.
In addition to the references below, the content is informed by training and information from the following teachers: Heather Mason; Mieke Kreeftenberg; and Charlotte Watts.
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