This month’s practice theme runs along a more conceptual framework. This March, we explore how you can integrate yoga into your life as a routine stress cycle disruptor. There is one thing that both ancient and modern sciences agree on, and that is the negative impact that chronic stress has on the immune system. The body has an inbuilt mechanism for dealing with stress. The HPA axis (hypothalamic-pituitary-adrenal axis) is our very own central stress response system. Designed to raise metabolic response as part of our evolutionary survival instinct when under attack, the HPA axis works well when both body and life are in balance. However chronic stress which causes your body to stay in constant flight or fight mode, can result in pathophysiological changes that suppress the immune system. Chronic stress can be described as a state where stress continues for a prolonged period of time, interfering with your ability to live a normal life, thus resulting in negative outcomes for your health, both mentally and physically. Let’s take a closer look at the multi-faceted aspects of stress.
Stress is multi-dimensional but beyond that it is also, practically speaking, subjectively felt and experienced. Stress can result from both emotional and physical threats. You can experience emotional stress from having a disagreement with a loved one and you can also feel stress because the ground you’re standing on is literally shaking because you’re in the middle of an earthquake. Objectively speaking, the latter scenario is life-threatening whilst the former is not. However as I earlier alluded, stress is also subjectively experienced. For some, having an argument with a loved one could amount to a life or death situation, particularly if the perceiver has a “catastrophic” psychology and imagines severe consequences might result from the argument. This is also where chronic stress can play a harmful role.
Stress activates the body’s HPA axis resulting in the release of hormones, one of which is cortisol. Cortisol also known as the stress hormone is released from the adrenal glands as a response to hormones originating from the hypothalamic and pituitary glands. Stress can actually be both beneficial and suppressive to the immune function. Acute stressors can enhance immune function whereas chronic stressors are suppressive leading to its over-activation.
Elevated levels of cortisol for extended periods of time however, ( as a result of the chronic stress cycle ) can produce a number of negative effects, one of which is altered cognition, perception and emotional reasoning. I cite a research report published in 2017 ( Brown, Raio & Neta ) in which a group of participants recruited from Nebraska-Lincoln University were asked to respond to facial expressions and to rate these as either happy or angry. The images comprised a set of 48 images – 24 being ambiguous, 12 angry and the remaining 12 happy. The testing revealed that the control group were more likely to rate ambiguous faces negatively after undergoing a stress test which coincided with higher cortisol levels in the bloodstream. The analysis indicated a positive correlation between stress group negative facial ratings and changes in cortisol levels. As I mentioned earlier, stress is subjectively experienced and the role chronic stress plays in the impairment of cognitive response can result in an unhealthy and ongoing cycle of negativity in which the physiological harms the psychological and vice versa.
The research interpretations sit well with neurological science and what we know about how different regions of brain function, in particular the amygdala with its high receptor density for glucocorticoids (cortisol). The amygdala is the part of the brain that contributes to emotional processing. It has a pivotal role in psychiatric disorders and is highly responsive to stressful events. An enlarged amygdala has been identified in some autistic children, and the larger this region of the brain, the more anxious and depressed a child is likely to be ( Zeliadt, N, 22 October 2019, reporting for Spectrum News on findings presented at the 2019 Society for Neuroscience Annual Meeting in Chicago ). The good news though is that the amygdala can also shrink with a little work. MRI scans show after an 8 week mindfulness practice that the amygdala appeared to shrink. And conversely as the amygdala shrank, the pre-frontal cortex, associated with higher order brain functions, such as awareness, concentration and decision making became thicker.
The cycle it seems travels in the direction of the cycle. Positivity begets positivity, whilst negative begets negativity. Hence, the need for stress cycle disruptors.
Chronic Stress and the Immune System
Just as the body has a stress response system, the body too has its own defence system. This defence system is a remarkable biological infrastructure which in its most complex hidden form encompasses a network of organs, cells and chemicals and in its simplest visible guise, other aspects of the human physiology including our skin and the little hair filters in our nostrils. These many different yet interlocking parts of the human biology somehow come together with the singular purpose of protecting the human body from its foreign invaders; in a healthy functioning immune system, that is. There are times when the immune system does not function as it should and when that is the case, the body becomes vulnerable to the attacks of its foreign invaders, viruses and pathogens.
One of the key suppressors of the immune system is chronic stress. Changes to lifestyle as a result of technological and scientific innovations have improved quality of life in many measurable ways. However these material improvements have also come at a cost and altered the nature of stress ( Liu Y, Wang Y, Jiang C, Inflammation: The Common Pathway of Stress – Related Diseases, 2017 ). Rather than short, episodic stress which the human biology was designed to deal with (e.g. running away from a tiger in the middle of a hunt for food), the modern lifestyle environment encourages insidious, low level yet continuous and compounding stress that can create a continual state of threatened homeostasis. The type of stress may not be life-threatening. It may also only be psychological or emotional, as opposed to physical. Yet these types of psychological stressors occur at a level high enough to induce the HPA axis to activate, over and over again for extended periods of time. Consider the “normal” stresses of modern daily living: the stress of finding a job, a first home, finding a girlfriend, making enough money to pay for a holiday, getting likes on social media and very simply, the continuous stress of existing and just being enough. Unless you live in a monastery, the cycle of stress that comes from the normal pressures of modern living is likely to continue and intensify rather than abate and the key to finding balance is in building into your routine stress cycle disruptors that can help bring balance back to the body.
Disrupting the Chronic Stress Cycle
More than ever, the discussion around how stress impacts the immune system is becoming more significant – psychological stressors are unlikely to abate and global pandemics are becoming a greater reality due to the ease of international travel. The most recent developments around Covid-19 virus is very much on point. How we handle a perceived threat is a function of our chronic stress load and how our bodies might handle a real viral threat is a function of how well our immune system is functioning and how well our immune system functions is affected by our stress mechanism. It’s a vicious cycle and a cycle that requires routine disruptors to help reset and bring the body back to balance.
Yoga in this regard is a powerful stress disruptor. Performed a few times a week, the practice has the capacity to produce short term benefits both physically and mentally for the practitioner. Continued over a number of years, yoga starts to have profound and longer term implications for the immune system. Our ability to handle stressful situations improve and if neurological science is correct, our ability to rationalise fact from fiction also improves through pre-frontal cortex strengthening; a real plus when we live in an environment where fiction is often hard to discern from fact due to the way in which information is transmitted through mixed media platforms and networks. In our classes this month, we will explore yoga’s potential as a chronic stress cycle disruptor. Yoga does many things and mean different things to almost everybody. Sometimes it builds bodies, other times a reprieve for emotional states. Yoga too can be a stressor, both positive and negative. What we want is to find a balance that will amount to a positive stressor through adjustments in movement tempo, breathing rates and postural choices.
All this March, exploring yoga as a chronic stress cycle disruptor and simultaneously strengthening the immune system through the spectrum of both Yin and Vinyasa classes.