The primary biochemical mechanism that facilitates fight-or-flight involves activation of the h-p-a axis – the link between the hypothalamus and the pituitary gland at the base of the brain, and the two adrenal glands above our kidneys. However, we’re not necessarily running or fighting for our lives – fight-or-flight is simply a consequence of the activation of the sympathetic nervous system, and it will happen even when we’ve been in waking sleep and someone calls our name. In this case the physiological effect will be very small and hardly noticeable, but what has happened is that the level of adrenaline in our system has increased to facilitate our waking up and orienting to the call.
At the other extreme, when we’re suddenly jolted by a loud bang the level of adrenaline increases dramatically.In these situations we can feel the effect on our heart – it starts to pound!This is all entirely appropriate. Adrenaline is not a ‘stress hormone’, just a hormone doing exactly what it is designed to do: facilitating a rapid response to demand.In the Challenge of Change Resilience Training we call the demand to perform pressure, and pressure is intermittent – it’s very rare to have constant sustained pressure. These bursts of demand are sometimes erroneously called ‘acute stress’, but they have nothing to do with stress – even if the demand is intense, it is still pressure.What transforms it into stress is rumination: in-between the peaks of pressure there is always the opportunity to return to rest, but continuing to ruminate about emotional upsets bridges the gap by maintaining the fight-or-flight response.
Our bodies operate on what’s called a homeostatic principle – it will intelligently return to rest as soon as possible after demand if we don’t interfere by ruminating. It does this in two ways. Think about pushing a car in neutral gear along a flat road. The movement of the car is like the burst of pressure, and you can just wait for it to gradually slow down and stop, or you can make it slow down quicker by applying the brake. This is just an analogy, but our bodies have two analogous processes in place so that it can come back to rest as quickly as possible.
The energy and movement from the push is the equivalent of the sympathetic activation system, with the increase in adrenaline. When the demand (the push!) stops, provided you don’t ruminate the adrenaline will be metabolized, heart rate slows and we gradually come to rest. The brake in the analogy is a parallel nerve system called the parasympathetic. The parasympathetic system is sometimes called the ‘rest and digest’ system, because in fight or flight our digestive process is slowed to conserve energy for action. Like the sympathetic system the parasympathetic is extremely complex, and we need to keep it as simple as possible by focusing on just one key nerve called the vagus. The vagus nerve has multiple functions, but here’s a simple demonstration of the one we’re interested in and can use in a practical way.
Place the index and middle finger of your left hand on your right inside wrist, and move them around gently until you can feel your pulse. Now take a deep in-breath, followed by a long out-breath. Do this a couple of times. Did you notice how your pulse (in other words, your heart-rate) increases as you breathe in, then slows down as you breathe out? That’s called heart-rate variability, and it is a healthy process of cardiac regulation.
Now do the same thing but instead of deep breaths just take shallow ones. There’s almost no change in your pulse. When we get anxious or upset we often don’t notice how our breathing changes to short and shallow, which is probably the reason for the old adage of stopping and taking a deep breath before you do something.
When you breathe in your diaphragm flattens and your ribs lift, which increases your chest cavity and your lungs expand to fill it.The vagus nerve passes through your diaphragm and is stimulated by these changes in your breathing.This is reflected in healthy heart-rate variability, and is sometimes referred to as ‘vagal tone’.You can’t actually ‘tone’ your nerves – this isn’t a nerve-gym! – but in practice, healthy vagal tone means regular heart-rate variability. Overall, the effect of stimulating the vagus nerve by breathing deeply and regularly is that variability is regulated and cardiac activity slows back to normal more quickly than just waiting for the excess adrenaline to metabolise.This is the equivalent of applying the brake.
So, you can make this a practice. When you find you’ve been ruminating about some emotional upset (i.e., stressed), you must already have woken up. Take control of attention, get into the loft and let the negative emotion go, then add to that a return to deep, regular breathing. Don’t gasp or strain – breathing is a very natural process, so just breathe in a deep and relaxed way.
An important caveat: the first step in the CoC programme is to wake and stay awake as long as possible. This means keeping control of attention as long as possible, and controlling attention is the key to the breathing exercise as well. So, really give your attention to each in and out breath. Notice for example the cool sensation in your nose as you breathe in and the warm sensation as you breathe out. The breathing exercise will be compromised if you continue to allow your attention to be snatched away into rumination – what we all know from practising the four steps is that rumination tends to be quite persistent! The negative thoughts will most likely keep returning, but with consistent practice of taking the four Challenge of Change steps that will happen less and less.