Stress is great. It makes us faster, stronger, more agile and our brains have better recall and flexibility. That's why people are willing to put themselves in stressful work situations or engage in extreme sports.
The problem is that uncontrolled, stress can leave us frozen to the spot and unable to think – something all too familiar for people having to speak in public or students sitting in the exam hall.
Stress developed because it gives an evolutionary advantage.
For early humans, and with predators everywhere, food could be scarce and diseases prevalent. By understanding what is happening inside our bodies and why, we can learn to control stress and use it our advantage.
Your body, when stressed
When you're feeling stressed, it's a sign that your body is going into emergency mode. The turbo button is pressed, the engine of your body has roared into overdrive and you become superhuman.
This means becoming ultra vigilant, able to react quickly and increase memory recall, and to remember every aspect of what you are seeing, hearing and feeling. It is this increased attention to detail that gives us the feeling of time standing still, during a car crash for instance.
This results in an increase in breathing, blood pressure and heart rate, to help pump blood and oxygen around the body more effectively.
At the same time the liver breaks down more glycogen, a high energy storage substance similar to the starch in plants. It is made in the body by combining glucose (sugar) molecules – and breaking it down again produces the glucose that our bodies actually use for energy.
Blood is moved from other areas of your body to support the muscles – which show increased strength and endurance. Your immune system switches up a gear and your blood prepares itself to clot – in case you're injured.
Your brain also starts working much better – fed by the glucose and oxygen being pumped around your body.
What about burnout?
Like a powerful engine, when we're stressed we burn hot, but if we do it for too long, we burn out.
In the short term, physiological changes, including increased blood pressure, higher levels of glucose in our blood and decreased appetite, are important adaptations, which normally cause little damage to the body.
Our bodies do their best to only use these stress adaptations when they are most needed – maximising the benefit and minimising the potential for damage. But despite this, the body tends towards stress, given its potential advantage in our survival.
Breathing to control stress
One of the simplest things you can do to relieve stress is to breathe – something we all know how to do. The presence of breathing techniques in both traditional meditation techniques and modern relaxation methods reflects the importance of taking deep breaths.
The immediate impact of doing this can be seen in the reduced production of one of the stress hormones, noradrenaline. Levels of cortisol, another stress hormone, will also start to reduce.
Research by scientists in the Howard Hughes Medical Institute, at Stanford University, have now identified that these changes are linked to a group of nerves in our brains called the "pre-Bötzinger complex", which regulates our breathing.
The scientists found that changes in the expression of certain genes in these nerves – which are physically connected to critical areas in the brain associated with relaxation, attention, excitement and panic – can calm an individual.
The clear implication being that changes in breathing directly affect stress levels.
Modern meditation techniques are epitomised in the concept of mindfulness, which brings together these breathing techniques and the idea of "living in the moment", putting concerns for the past and future into context.
Psychologically, this helps to reduce the level of anticipation associated with unnecessary forward planning and concerns, while physically reducing important stress hormones.
By learning simple coping strategies, understanding what makes us stressed, keeping stress at manageable levels through breathing techniques, and taking regular breaks from it, we can begin to learn to use stress to our advantage, rather than letting it control us.