Just Breathe: The stress-relieving effects of Sudarshan Kriya Yogic Breathing

The feeling is the same for all of us - whether you recognize the symptoms as your hands shake at the start of a speech or when you lay painfully awake thinking about tomorrow’s exam trying to sleep. We all recognize the symptoms of stress, but few understand the bodies underlying mechanisms in dealing with it. Just under the surface of our anxiety is an elaborate and delicate system working itself out.

Stress has its benefits. Its evolutionary roots were selected to keep our ancestors alive. While the stress humans experience today is less severe than what our ancestors put up with, it can still enact equally as taxing a response to our bodies. Perhaps even more so. The same nerve and chemical stimulation that a forager would have escaping for their life, we enable stuck in traffic, late for work.

It seems fairly safe to assume that people today experience less life-threatening, but far more psychosocial stress. So what happens when we’re so continually stressed out our bodies can’t jump our of ‘adrenalate’ mode (commonly expressed as ‘fight or flight’)? Stress easily reaches chronic levels that have harmful, deleterious consequences, ranging anywhere between fatigue and muscle loss to heart disease and diabetes.

But before that sentences alone stresses you out, let me present the good news. Slow breathing techniques, characteristic of yogic breathing, can physiologically reverse the effects of stress by activating the Parasympathetic Nervous System (PNS), also known as the ‘vegetative’ or ‘rest and rebuild’ state. So while stress can have serious consequences to your health, you may be happy to hear you have the final say in managing it.

Before I jump into the findings of Brown and Gerbarg, documenting the effects of Sudarshan Kriya yoga, let me brush up on a bit of biology. The malaffects found caused by chronic stress are hormonal in nature, though it all leads back to what is triggered by our nervous system, through its voluntary and involuntary aspects.

There are two major divisions of the involuntary/autonomic side of that system: the Sympathetic Nervous system (SNS) or ‘fight or flight’ overdrive mode, and the Parasympathetic Nervous system (PNS) or the ‘rest and rebuild’ healing mode. Ideally these two factions have a give and take relationship, trading off the workload when environment is appropriate for one over the other. So as parasympathetic tone goes up, sympathetic tone goes down.

However, its possible for one to try to trump the other for mechanistic control. This can be most damaging when it’s the SNS fighting for attention. And I do mean fighting. The tendency of the SNS is to allocate all possible sources of energy to maximize motor use, leaving less for maintenance and functioning. This means, the SNS is not utilizing energy to repair tissues (i.e. muscle, brain, ect.), metabolize nutrients or fortify the immune system. It is meant to activate quickly and end quickly.

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However, it is not uncommon in our modern lives to let psychosocial stress take the wheel and control the allocation of energy resources. This can exacerbate pre-conditions and lead to many diseases and illnesses, among them: depression, chronic pain, heart diseases and disorders, immunity disorders, impaired cognition, pre-aging, diabetes and more. Luckily, Brown and Gerbarg have proposed a viable alternative to letting stress run your life (2005).

The best part is, this technique can be used by anyone, anywhere and, aside from learning the technicalities involved in the practice, all you have to do is breathe! For 8,000+ years the yogic masters have claimed that the art of yoga is an exercise in strengthening the connection between the mind and the body. Science is finding more and new ways that our mind affects our brain, which affects our whole body and well-being and visa versa. Many of these pathways are related to the stress-response.

Brown and Gerbarg measured the neurophysiological changes in the body when using mind-body interventions, outlined by Sudarshan Kriya yoga (SKY) techniques, including different rates of breathing, breath-holding, posture, air resistance upon others (2005). If you’re interested, these breathing methods are more detailed and/or efficiently taught by instructors at the Art of Living academy; a link to their site can be found here.

The study focused on stimulation of the autonomic nervous system functions, measured by heart rate variability, cardiac vagal tone, chemoreflex sensitivity (O2 and CO2 levels in blood), baroreflex (blood pressure), and central nervous system excitation (Brown & Gerbarg, 2005). Recent research has even focused on cardiac vagal tone (the PNS is primarily associated with the vagus nerve) as a marker of emotional regulation, psychologic adaptation, emotional reactivity/expression, and empathic response and attachment (Brown & Gerbarg, 2005).

First off, the relationship between breathing and emotion are bidirectional. Breathing is one of the few bodily mechanics under both voluntary and involuntary control through complex feedback mechanisms involving autonomic visceral networks, parts of the brain stem, limbic system, cortical areas and the neuroendocrine system. Breathing that is highly connected to the autonomic nervous system is also highly influential on emotion and mood (Brown & Gerbarg, 2005).

Sudarshan Kriya yoga involves four different components in breathing techniques. Again, if you wish to know more, visit there website to get a more detailed account of the techniques. I’ll refrain from describing them since I’m not a qualified instructor and many nuances are involved that is best explained in person and through practice.

Slow yogic breathing decreases chemoreflex sensitivity (mediated by the vagus nerve), improves cardiovascular and respiratory function and increases arterial baroreflex sensitivity (Brown & Gerbarg, 2005). In other words, this slow breathing decreases the involuntary respiratory responses to small changes in O2 and CO2 levels in the blood, improves circulation and breathing function and increases the vascular system’s sensitivity to changes in blood pressure.

Reducing the chemoreflex sensitivity allows the body to tolerate higher levels of carbon dioxide (which is generated during exercise). In fact, the chemoreflex sensitive affects of yogic breathing practices mimic those found in elite athletes, specifically in that the body is able to sustain higher levels of carbon dioxide, while better utilizing oxygen levels.

Adaptation of pulmonary stretch receptors to deep breathing and chemoreceptors to chronic high levels of carbon dioxide retention increases vagal nerve stimulation to the brain causing physically and emotionally calm effects (Brown & Gerbarg, 2005). And continued yogic breathing practice decreases heart rate, increases vagal tone and increases aerobic capacity, all of which are influenced more so by introducing yogic postures and poses (Brown & Gerbarg, 2005).

Resistant or pressure breathing which is a component of SKY, caused by a slight contraction of the laryngeal muscles, stimulates the somatosensory vagal afferent nerves leading to the brain, increasing vagal tone, in so increasing the PNS (Brown & Gerbarg, 2005). Furthermore, regular slow breathing normalizes baroreflex sensitivity, which is compromised with aging, cardiac disease and hypertension, all of which are exacerbated and even caused by stress (Brown & Gerbarg, 2005). Slow yogic breathing not only lessens the response to stress – it actually reverses it!

The SNS and PNS are constantly dispatching signals to the body with every breath. Normal heart rate increases during inspiration and decreases during expiration. This interplay, however, is influenced by sympathetic and vagal/parasympathetic input and by respiratory rate and volume (Brown & Gerbarg, 2005). Simply enough, exercising the vagal/parasympathetic tone improves (often by decreasing) normal heart rate.

Furthermore, as polyvagal theory purposes, vagal activity is linked to attention, emotion and communication (Brown & Gerbarg, 2005). Slow yoga breathing, stimulating the PNS along with its varied effects mentioned previously, activates the hypothalamic vigilance area and induces a calm but alert state, recharges energy reserves and prepares the body for future stressors. This is the natural state of the nervous system experienced by our evolutionary ancestors – calm, alert and maintained during the majority of experience and heightened by stress to maximum energy output when occasionally needed.

This slow and deep yoga breathing can mechanistically switch off the Sympathetic Nervous system and shift to the Parasympathetic Nervous system via vagal stimulation from vagal somatosensory afferents in the glottis, pharynx, lungs and abdomen (Brown & Gerbarg, 2005). Even without long-term practice, these techniques have shown to improve all the areas mentioned previously and only grow stronger with time.

Often when telling the brain what to do - like “go to sleep” –  enacts the opposite response. So in times of stress, when your mental capacities aren’t doing you anymore good, but you simply find it impossible to escape your thoughts, just breathe…

Reference:

Brown, R. P. &, Gerbarg, P. L. (2005). Sudarshan Kriya Yogic Breathing in the Treatment

            of Stress, Anxiety, and Depression: Part I—Neurophysiologic Model. The

            Journal of Alternative and Complementary Medicine, 11(2), 189- 201.

            doi:10.1089/acm.2005.11.189.