Rest And De-stress: The Vagus Nerve And Yoga

Your path to Wellbeing And Happiness
Access the Power of the Vagus Nerve Through Yoga

In today’s fast-paced world, acquiring tools to support your physical and mental wellbeing is an imperative. This is borne out by the world-wide popularity of mind-body systems such as yoga: an ancient discipline, offering you peace, tranquility and wellbeing supported by a large body of evidence demonstrating valuable physical and mental health benefits. A major component of yoga’s effects on your wellbeing in the action of the 10th cranial nerve, the Vagus

The Vagus is the main distributor of signals from the rest-and-digest parasympathetic nervous system (PNS), an inbuilt mechanism that helps you mitigate stress. Working though the Vagus, the PNS plays a vital role in supporting all your vital organs. Vagal activity lowers your blood pressure and heart rate, stimulates the movement and absorption of food in the gut, and generally supports the life processes needed for optimal health

Mentally, PNS activity has a positively calming effect, promoting relaxation, reducing stress, and lifting your mood

In this article, we will discuss the theory and practice behind yoga’s effects on the vagus nerve and your health, exploring the science and describing some specific exercises to maximize Vagal activation

Whether you’re new to yoga or a seasoned practitioner, understanding this powerful connection can help you harness the full potential of your practice to enjoy greater health and well-being

Stress And The Vagus Nerve

At its most basic, stress is your body’s way of dealing with life’s challenges, great or small. While our conscious experience of stress is largely mental-emotional, stress is associated with a series of powerful changes involving multiple organ systems

Under stress, the brain triggers the  general adaptation syndrome (GAS), a cascade of hormones culminating in the release cortisol from the adrenals to help you deal effectively with stress

The GAS is described in 3 stages:

1. Alarm: an initial response of fight-or-flight, with increased heart rate, blood pressure, and mental alertness. This is mediated through cortisol in tandem with the sympathetic nervous system (see below)
2. Resistance: where the body tries to counteract the potential damaging effects of the alarm stage, and return your vital parameters back to baseline. This action is mediated via the parasympathetic nervous system (see below) via the Vagus nerve
3. Exhaustion: where persistent stress finally depletes your body’s energy resources with negative consequences for your physical and mental health

The GAS is a stereotypical response, appearing the same whether you’re experiencing excitement or distress. More recent research, however, suggests mental attitudes such as positive thinking and optimism have a mitigating effect on the ill-effects of stress

Autonomic Nervous System

The GAS works in tandem with the autonomic nervous system (ANS), part of the nervous system involved in regulating all of your vital functions

The ANS is comprised of two complementary systems:

• the sympathetic nervous system (SNS) creating physiological arousal in response to stress, and
• the parasympathetic rest-and-digest nervous system (PSNS) returning your body to baseline to replenish your energy resources

Though their actions are often antagonistic, the two systems work synergistically to produce a level of excitation, or autonomic tone, appropriate to an ever changing physical and mental environment. Check the diagram below to see how the ANS affects the major body systems

Stress And Health

Triggered by stress, the sympathetic nervous system releases the hormone adrenaline and neurotrnasmitter noradrenaline to create the fight-and-flight response

The emergency dealt with, the resistance stage of the GAS kicks in mediated by the parasympathetic and Vagus to return your body to rest-and-digest

While acute stress is healthy and necessary, persistent stress depletes your body’s resources, leading to negative health outcomes

In the short term, chronic stress is associated with functional (psychosomatic) disorders such as abdominal bloating, indigestion, irritable bowel, and mood disorders including anxiety and depression

Longer term, stress is linked with some of the commonest diseases of our age, including clinical anxiety, major depressive disorder, obesity, hypertension and cardiovascular disease

Stress, Rest & The Vagus

Under resting conditions, the parasympathetic system acts via the Vagus to maintain a state of relaxed calm supporting healing, repair and the maintenance of healthy function

Known as the wanderer, due to its extensive distribution, the Vagus exits from the brain-stem to supply your vital organs. Activation of the vagus is associated with a reduction in heart rate and blood pressure, and a boost in digestive function

The Vagus is strongly anti-inflammatory, supporting immune activity to assist healing and repair

Stress, The Vagus Nerve And Yoga

Despite their physical effects, stress and rest are mental appraisals of any given situation as inherently safe or unsafe

Moreover, during stress your body responses are similar whether you’re encountering an external challenge, recalling a past event, or anticipating a future scenario

While in some cases involving past trauma psychotherapeutic support can be invaluable, under normal conditions yoga can help you shift the brain bias in the direction of rest

Studies show that mindful practices such as yoga, tai ‘chi, Pilates, and others have a powerfully relaxing effect, decreasing key markers for physiological stress

The Vagus As Mind-Body Link:
The Gut Brain Axis

We’ve already seen how the GAS together with the autonomic nervous system links your mental state with your body physiology

The Vagus distributes parasympathetic signals to the organs, but the Vagus contains nerve fibres serving different functions, including the control of the voluntary muscles of speech and importantly, sensory fibres from areas of the skin AND the internal organs. In fact as much as 80% of the Vagus is sensory 

The Vagus is the principle pathway connecting the internal organs with the brain. This is well illustrated in a bilateral relationship between the digestive tract and nervous systems known as the gut-brain axis

A particularly fruitful area of study has been the discovery of the chemicals mediators produced by the microbiata, the colony of micro-organisms living in your gut. Of special interest is the mood-enhancing signalling chemical serotonin: though traditionally considered a brain neurotransmitter, as much as 95% is produced by bacteria in the gut !

Thus, gut bacteria communicate with your brain, just as your mood can influence your gut health through in a two-way feedback loop mediated by the Vagus

Does Yoga Stimulate The Vagus Nerve?

Direct stimulation of the vagus kicks off with the development of a technique to send an electric current to the nerve for the management of certain treatment-resistant conditions

Currently licensed solely for the treatment of epilepsy and depression, the wellness community have embraced Vagal stimulation, claiming to do so by means of pressure, massage, exercises and even cold applications. But can yoga really stimulate Vagus nerve?

Vagal activity is usually measured through the phenomenon of heart-rate-variability (HRV). Calculated as the difference in heart rate during inhalation and exhalation, HRV is considered by many, though not all, a measure of Vagal tone

• In a 2016 comprehensive review of the literature A. Tyagi and Marc M Cohen found that despite their poor methodology:

the reviewed studies suggest that yoga can affect cardiac autonomic regulation with increased HRV and vagal dominance during yoga practices. Regular yoga practitioners were also found to have increased vagal tone at rest compared to non-yoga practitioners

• More recently a 2023 systematic review by Rani Jose et al concludes that:

Physical exercise, breathing exercise, diet, music, and mind-body interventions such as yoga and meditation were identified as the factors enhancing HRV or predictors of HRV

If the evidence for yoga stimulating the Vagus needs further elucidation, yoga’s ability to reduce stress markers is firmly established

Yoga Benefits Mediated By The Vagus

Treated as a holistic system incorporating postures, breath-work and mindful focus, yoga has been shown to reduce physiological arousal to improve the major risk factors for cardiovascular disease, including a lowering of blood pressure and improvements in the cholesterol profile, shifting the balance towards good cholesterol while reducing the total levels of circulating fats

A systematic review by Cramer et al (2014) on risk factors for cardiovascular disease considers yoga to be an effective:

ancillary intervention for the general population and for patients with increased risk of cardiovascular disease

A systematic review by S Alra et al (2022) on yogic interventions compared with usual care and non-pharmacological treatment in patients diagnosed with cardiac disease found:

strong evidence of effectiveness of yogic interventions on lipid profile, blood pressure, and psychosocial outcomes in patients with diagnosed cardiac diseases

Yoga is also associated with improvements in digestive health and associated mood-related symptoms in a number of disturbances, including irritable bowel (IBS) and inflammatory bowel disease (IBD)

A 2024 systematic review (E R Thakur et al) looking at the effects of yoga on digestive disorders, including IBS, IBD, chronic pancreatitis and gastrointestinal cancer, concludes that:

yoga appears to be safe and has potential to improve functioning across a spectrum of gastrointestinal diseases

The therapeutic effects of yoga on anxiety, depression and other aspects of emotional and cognitive health are equally compelling

Systematically reviewing 25 studies, M C Pascoe et al (2015) conclude:

yoga practice leads to better regulation of the sympathetic nervous system and hypothalamic-pituitary-adrenal system, as well as a decrease in depressive and anxious symptoms in a range of populations

Another systematic review headed by J Martinez-Calderón (2022) looking at yoga for anxiety and depression conclude that:

yoga-based interventions may help to improve mental health in adults diagnosed with anxiety or depressive disorders

Yoga Postures For Vagal Stimulation

Despite the many claims, discreet benefits from specific yoga asanas is not supported by the science, which favours a more holistic of mind-body practice with mindfulness it its core

Yoga may stimulate the Vagus at the level of the neck, chest and abdomen through breath, pressure and other stimuli

Commonly recommended exercises to stimulate the Vagus include

• Kapala Bhati (Shining Skull) and Bhastrika (Bellows) breathing
• Chest opening back-bends such as the Cobra (Bhujangasana), Camel (Ustrasana) and Bow (Dhanurasana)
• Inversions such as shoulder (Salamba Sarvangasana) and head stand (Shirshasana)
• Any and all of the 3 locks (Bandhas) may stimulate the Vagus

Again, despite claims by adherent of different schools, the relative benefits of different styles and methods of yoga over others remain unknown. I’ve heard it said that restorative or yin yoga is a good choice for increasing Vagal tone. It’s certainly not a bad choice. But assuming outcomes based on mechanisms is unreliable at best, and misleading at worst

The results of any intervention can only be known by studying outcomes. And practiced as a holistic system integrating postures, breath-work and mindful focus, yoga as a whole has been linked to no end of health benefits.

Choose a style of yoga that resonates with your qualities and that you enjoy. Move fast, or go slow. But always pay attention: yoga is none other than meditation

Check out my regular weekly class: Yoga For Vagus Nerve Activation

Meanwhile here’s a little something to tide you over and hopefully whet your appetite. The video below guides you through a simple body scan in preparation for a deeper relaxation practice known as nidra. Check my yoga nidra post

Yoga Breathing And The Vagus Nerve

Considered the principal manifestation of the vital force (prana) within the body, breath is at the centre of all yoga practice. Breath is a vital mind-body link, it’s condition revealing your mental state, as much as your mental state reflects the pattern of your breathing

Breath regulation is a powerful stimulator of Vagal parasympathetic activity, bringing about positive and lasting changes to your wellbeing

The subject of breathwork is very great. The physiology of breathing and overbreathing and its connection with the autonomic states of anxiety and calm is a fascinating topic which will be dealt with in a forthcoming article

Yoga breathwork, or pranayama, translates as restraint of the the vital air, with prana as the subtle energy, or life-force manifesting in the body as breath, and in the mind as thinking and feeling

When prana moves the body is active and the mind thinks and feels. When prana is still the mind is clear and calm and the body rests

Underlying the countless classical classical and modern takes on breathwork, the underlying principle of pranayama holds: breathe less. Calm, quiet breathing is associated with parasympathetic activity, soothing the mind and relaxing the body

Practical: Breathing For Vagus Nerve Activation

Practical

Sit comfortably, or lie on your back

Breathing in and out through your nose notice where you feel the breath: in the various parts of the nose and throat; is your chest breathing? Is your belly moving with your breath? Does your breath reach your lower ribs? At the from. the sides, or the back? Use your hands to help you, if you like

Is there a place in the torso where you don’t feel the breath at all? Mentally soften this area, and see if you can feel it respond to the breath. Don’t try to direct the breath in any way. Just soften areas of tightness and observe. Nothing may change. That’s OK

Now as you let the breath go, exhale quietly and slowly through your nose. Let the exhalation tail off and finish completely. Now wait a moment. Does the breath restart immediately, or is your body comfortable pausing before inhaling?

When the breath comes accept it. Notice where in your body yo can feel the inhalation, followed by the exhalation

Practice breathing this way, initially for a minute or two, building up to 5 minutes as you gain familiarity and experience

Conclusion: 

The evidence shows that health-giving secret of yoga is not to be found in performing this or that set of asanas or breathing exercises, but by reducing excessive physical and mental activity through mindful awareness

Find a style that you enjoy, that you feel motivated to practice regularly. Work with a teacher who understands your needs and supports your goals. Or practice in splendid isolation in your own safe place. Move fast, or go slow. But always pay attention: meditation is the soul yoga

Above all, enjoy, enjoy, enjoy