The Body’s Fight or Flight Response

The body responds to threat using a response called fight-or-flight. This is also known as the acute stress response. This terminology describes the body’s physiological reaction to something that is extremely physically or mentally frightening. The response occurs due to the body’s natural hormones that are released to prepare your body to stay and fight whatever is in front of you, or run away to somewhere safe. This is a natural human and animal instinct that has been around since our ancient ancestors had to choose between fighting or fleeing the danger they faced. This is the body’s physiological and psychological response to stress. 

It was American physiologist, Walter Cannon, who first coined the term “fight or flight” when he realised that certain reactions took place inside the body when a person was faced with a threatening situation. These reactions helped mobilise all the resources needed to deal with the imminent danger. 

The Fight or Flight Response Explained:

When the body is faced with acute stress it causes a sudden release of hormones which activate the body’s sympathetic nervous system. The nervous system then stimulates the adrenal glands which release catecholamines. Catecholamines are comprised of both adrenaline and noradrenaline. This release tells the body to speed up its heart and breathing rate as well as blood pressure. Once the threat is no longer there, it will normally take the body up to 60 minutes to return to its pre-arousal state. If you think back to the last time you experienced something thrilling or frightening, I’m sure you were aware of how your heart and breathing rate sped up and that your whole body was tense, ready to take action. 

This fight or flight response can happen when you are faced with some sort of physical danger, such as a vicious dog growling and barking at you, or what you may understand as a psychological threat, like having to take an important exam or stand up and speak publicly. 

Physical Signs of the Fight or Flight Response and their Function: 

Increased heart and breathing rate: This happens so that you can provide the extra energy and oxygen to your body needed to fuel an immediate response to the threat. 

Dilated pupils: Your pupils dilate so that you are able to receive more light into your eyes. This gives you the ability to see your surroundings better which is necessary as you need to be hyper observant and vigilant during times of danger. 

Your skin becomes pale or flushed: As your body prepares you to either fight or flee the blood leaves the surface of your body and goes into the important large muscles needed to take action. This can leave you looking paler than usual. The blood also rushes to the head and brain, so you could also alternate between both looking flushed when this happens and pale as it drains into the muscles. During times of stress, your body’s ability to clot its blood also increases. This is in case you are wounded from the threat and will prevent you from losing excess blood. 

Shaking: When faced with an imminent threat, or under stress, your body becomes primed and it tenses up – ready to act. When your muscles are so tense they may start to shake or tremble. 

Why it is needed:

The fight or flight response is critical for our survival. It prepares the body to act in the face of an immediate threat. However, this response can also be triggered when the threat is imaginary or historical. 

The stress that your body is put under in a scary situation can be useful as it makes it more likely that you will be able to cope with the threat. Psychological stress can actually help you perform better in certain situations where you are required to do well, such as at work or school. In the event that you do actually run into immediate and life threatening danger, the fight or flight response is there to give you the best chance of surviving. 

Because the response is automatic, it is not always accurate. You may find you respond this way even when there is no real, visible threat. It is what Benjamin Fry refers to when he talks about “the invisible lion” in his book of the same name. It is possible that our fight or flight response has been previously triggered in the face of a very real threat, but then if not discharged properly, it remains somewhat dormant in us until triggered again in the present, less threatening context, releasing the same reaction it necessitated in the first instance. 

One way to help you cope with situations like the invisible lion is to understand the body’s natural fight or flight response. When you notice that this reaction is kicking in and you are becoming tense, you can teach yourself ways to calm you down.