Fight or Flight (Tips)

Fight or flight is most commonly known as the physiological reaction that we have whenever we identify any harmful presence or situation in our path.

Fight or flight is intended to keep us safe and on the lookout for any potential threats.

Walter Bradford Cannon, who was a famous American neurologist and physiologist, was the first one to identify the physiological and psychological components of the fight or flight response.

His theory stated that animals generally react to attacks or threats from other animals by reading signals from the sympathetic nervous system.  

Fight or flight is considered one of the earliest indicators of a condition called general adaptation syndrome, which is a way that we process stress reactions and responses as vertebrae and living organisms.

The fight or flight response manifests itself in a variety of physiological ways.

Some symptoms most commonly associated with fight or flight include: increased heart and lung activity, paling of the skin, feeling flush, slowing down or stopping the digestive process, contracting your sphincter, and the dilation of blood vessels and pupils.

Additional fight or flight symptoms are loss of hearing, constricted blood flow to certain body parts, relaxing of the genitourinary system, erectile dysfunction [in males] and a loss of peripheral vision.

These symptoms can be quite distressing to anyone who experiences them, even if it is the body’s way of making sure that we stay safe in a very threatening situation.

All of these symptoms essentially serve a greater function in helping us defend ourselves physically and mentally. 

Function of physiological changes:

The physiological reactions that happen in the fight or flight response are meant to give the human body as much strength as possible so it can respond quickly in a threatening situation.

Some ways in which the body accomplishes this is by increasing our blood flow, changing our blood clotting function and increasing our muscle tension.

Although these physiological functions keep us safest in the face of grave danger, it is also possible that our fight or flight system can be activated when there is real threat [only a perceived threat] that faces us. 

Emotional components:

Fight or flight not only manifests itself with a physiological response, but it also plays an important role in regulating our emotions in the face of danger.

This response allows us to control our emotions and react quickly and accurately to whatever threatening situation crosses our path.

The main purpose of being able to regulate our emotions is ultimately to prevent ourselves from becoming overwhelmed by stress and being able to control our emotions when we are being tested by a threat.

During a fight or flight response, the intensity of our emotions also signals to us how much danger we are in or are about to face.

Yet it’s important to remember that if our emotions run too high, we might experience heightened levels of depression, anxiety and aggression.

These will undoubtedly have an impact on how we live our lives and how we respond to stressors.

Along with emotional changes, fight or flight will also manifest itself in our endocrine and nervous systems; the former will secrete certain stress hormones and the latter will send signals to other parts of our body to protect ourselves.

Purpose of the Fight or Flight Response:

When we are born, we are not instructed on how to react to certain situations. A lot of what we know is based on the experiences that we live through and what we learn from those experiences.

If we knew everything about the way our body responds to stress from the start, then we would probably have an easier time figuring out why we respond the way we do in dangerous situations and would likely feel a lot less stress.

However, since human behavior is unique in that it changes over time, especially in new environments and with new developments, we are also going to develop new thoughts that may not have existed in earlier times.

Part of human evolution means that we forget some of our evolutionary roots and we keep developing as much as possible to allow space for psychological growth. 

Although a lot has changed over time, the fight or flight response is still considered a driving force in the way that humans behave.

Its name alone demonstrates exactly how we react under stressful conditions.

As humans, if we know and understand what and why the fight or flight response exists, then we can more closely observe our behavior when we are feeling angry, stressed out, or threatened. 

When we start to feel stressed out, one of the earliest physiological indicators is that we can feel our heart rate increase.

Some people might start to feel pressure in their chest or feel like there is a heavy object pressing down on their chest cavity.

When you are stressed out, you become more sensitive to the stimuli, surroundings and changes that exist in your environment.

The stress signals to the body that it is time to do one of two things: fight, or flight. 

Our nervous system is heavily involved in the fight or flight response. Our sympathetic nervous system prepares the body to react and fight against the attack or to run away from it entirely.

When the threat passes, or is removed from the situation when you flee or defeat it, it will take up to an hour for the sympathetic nervous system to return to its baseline operating level.

Understanding how long our body takes to respond and recover is very important in understanding how fight or flight influences how we behave. 

If our minds and bodies adapt to our physiological changes, then the threats that approach us appear a little less shocking or surprising.

In earlier centuries, around prehistoric times, people had to make very fast decisions because if a person spent a lot of time thinking about how they were going to respond to a situation, then they might have been attacked by another person or eaten by a wild animal.

This response system allowed people, then and now, to make very fast judgment calls on how to keep themselves safe.

In some cases, this response is the very thing that may save your life.

One source of the fight or flight response is a phobia to something or a situation.

The response is often observed in people who are afraid of heights. If someone were to go to the top of a very tall building, then their heart rate and their respiration rate would likely increase significantly.

The same might happen to someone who is terribly afraid of crowds and finds themselves in the middle of a crowd of a thousand people. 

The fight or flight response is often observed in animals as well. For instance, imagine that a zebra is grazing in a field and suddenly a lion comes darting toward it, preparing to attack.

The zebra will experience a stress response that will show it the best way to escape from the predator.

The escape route will need to be fast and effective in order to keep itself safe from the predator and it must be supported by the entire physiological and nervous system.  

Another animal behavior example of fight or flight response can be observed in a fight between a cat and a dog.

The cat will likely experience an increase in its heart rate and its pupils will be dilated. The fight flight response deals with uncertainties, threats and attacks that it does not face on a daily basis.

Both animals and humans alike experience fight or flight as a safety vehicle, and understanding how that vehicle operates is key to knowing how we’re going to react in threatening or stressful situations.

The physiological and nervous systems work together to make sure that when faced with an external threat, we can react as quickly as possible to choose the path of defense or escape that is most suitable for the given situation. 

Fight or Flight FAQs:

How long does the fight or flight response typically last?

People experience symptoms of fight or flight over varying periods of time.

Some people will experience symptoms for minutes whereas others may experience symptoms for up to or over an hour.

From a physiological standpoint, the sympathetic nervous system will take about one hour to return to its baseline after being activated in a fight or flight response.

Can I stop the fight or flight response?

The fight or flight response is something that we have no control over.

However, we can be aware of the symptoms that accompany a fight or flight response so that we feel less stressed out in the face of a dangerous situation.

There is no way to stop the fight or flight response from happening, but we can be prepared by understanding how it works and how it serves us. 


Interested in Learning More? Check out these books on fight or flight:

Your Survival Instinct Is Killing You: Retrain Your Brain to Conquer Fear and Build Resilience

Fight or Flight: Negotiating Crisis on The Front Line

Beyond Flight or Fight: A Compassionate Guide for Working with Fearful Dogs


Duval ER, Javanbakht A, Liberzon I. Neural circuits in anxiety and stress disorders: a focused review.Ther Clin Risk Manag. 2015;11:115-26. doi:10.2147/TCRM.S48528

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