The Science of Stress - What sabre tooth tigers and Social media have in common

Do you ever feel like you’re on a roller coaster? You want to slow down or get off but you have no idea how?

You may have noticed the getoutside hashtag bouncing around on social media - a message that, underneath the dazzling array of perfect pictures, is actually worth paying attention to! Spending time in nature once a day is incredibly therapeutic and will help you take control of that rollercoaster. 

Over my career I have looked after hundreds of people in the wilderness, and increasing numbers of both adults and children write on their medical forms that they have been diagnosed with stress and anxiety related issues. 

Initially I wondered whether this was due to doctors more freely diagnosing this but soon realised there genuinely has been a rise. But why should we be worrying or feeling stressed in our modern world where we have everything we need on tap?

Let’s take a look at the science behind stress. It’s a perfectly natural response, hard wired into humans and all animals. Imagine you’re about to cross the road. As you step out, you leap back as a car hurtles past. Your body moved itself out of harm’s way but you are left feeling shaky, breathless, slightly sweaty with a racing heart.

Let’s break it down.

As you go to cross the road you look for traffic, you listen for the sound of an engine. Your eyes and ears send a message to the amygdala, a tiny part of the brain used for emotional processing. The amygdala deems it safe to cross and you go to step out, still looking and listening. A car is now coming towards you. Your eyes and ears send a new set of images and sounds to the amygdala that there is danger! The amygdala sends its danger alert to the Hypothalamus, the command centre of the brain, which then sends a message to the body through the autonomic nervous system.

The autonomic nervous system is made up of two systems; one of which is responsible for the ‘fight or flight’ reflex. This reaction triggers the release of adrenalin into the blood stream which makes the heart beat faster, sends blood to muscles, raises the pulse rate and allows the lungs to take in more oxygen with each breath, which is sent to the brain, heightening the senses. Adrenalin triggers the release of blood sugar and fats from temporary storage within the body into the blood stream, sending an energy supply to all parts of the body. At this stage the body steps backwards to safety, but the effects are still felt, hence the breathlessness, racing heart and shakiness.

All this happens faster than we are consciously aware of and the car can have passed

before we realise what has happened. The eyes look again and now see no danger, you cross the road safely and carry on with your day. The amygdala and hypothalamus, happy there is no imminent danger, calls the other part of the nervous system into play, relaxing the system and recovering. If the danger was not over, the secondary component of the stress response

kicks in causing the hypothalamus to release hormones which travel to the pituitary gland, and triggers the release of another hormone which travels to the adrenal glands, prompting them to release cortisol. This means the body stays wired and on high alert. When the threat passes, cortisol levels fall.

The science becomes relevant if you’re feeling stressed and overwhelmed. The fight or flight reaction is an incredible survival mechanism, designed to help keep animals and our ancestors alive. However, the senses cannot distinguish between a real or perceived threat. Have you ever felt your heart start racing, or felt slightly breathless when you’re running late? 

Fight or flight cannot differentiate between the almost definite pain (or death) of being hit by a car versus running late. We know it’s not life or death if we’re late for a meeting but your body cannot tell the difference and it is reacting faster than we can consciously think. For our ancestors, this response would have been short lived to protect them from harm. In the modern world, we are surrounded by so many perceived threats that our system is constantly on overdrive and this is not sustainable. Like any engine or energy system, this will become overloaded or run out of energy at some point.