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  • Writer's pictureJessica Lankmann, RP

Our Fight-or-Flight Response Explained

The fight-or-flight response is a significant component of anxiety that if not given enough importance can easily be misunderstood.

In my previous blog posts, I have spoken a lot about how anxiety occurs at the level of our thinking. I have walked you through how to create a worry period and how to distinguish between helpful and unhelpful thought patterns. However, I would be doing you all a disservice by just focusing on the thought part of anxiety.

When we start to feel anxious, stressed or panicked, not only do our minds go into overdrive, but so do our bodies. It has been my experience that sometimes the physical side of anxiety can be more overwhelming than the psychological side. So this blog post is dedicated to explaining, not only what physical changes occur when we are anxious, but why. The WHY being the important part. I will also walk you through a breathing exercise that can be helpful in decreasing your physical anxiety response.

When we perceive something as threatening or frightening our body is programmed to immediately respond by undergoing an accumulation of physiological (physical) changes. This can happen because of a physical threat, for example, someone acting aggressively towards you, or a mental threat such as preparing to speak publicly. These physiological changes are known as the fight-or-flight response.

two birds flying and fighting over food

What Is The Fight-Or-Flight Response And How Is It Helpful?

The fight-or-flight response is a series of physiological changes that occur in the body. These changes happen in response to a threat that activates our sympathetic nervous system. Essentially the sympathetic nervous system is responsible for all the physical changes that occur when we get anxious, such as increased heart rate, sweating, and shallow breathing. Once this system is turned on, our body begins the process of getting prepared to either run away or fight a potential threat. It helps to make us faster and stronger to assure our survival.

During the fight-or-flight response, our body starts to work extra hard to make sure we can respond appropriately to the situation at hand. When the threat is a physical one, we tend to not give it much thought and don’t really notice it. For example, if I am getting chased by a bear, the last thing I am worried about is my increased heart rate or overactive sweat glands.

BUT, when the threat is psychological in nature our attention is drawn to these physical changes, which are unpleasant. For example, if I am getting ready for a job interview, my increased heart rate or overactive sweat glands become the centre of my attention.

Our modern world has changed so much over the years that most of the threats we come across are no longer physical in nature, but rather psychological. What this means is the fight-or-flight system is no longer needed as much as it used to be. It’s kind of outdated.

Oftentimes, people begin to hyper-focus on the physiological changes that come along with the fight-or-flight response. Because there is no physical threat, the brain struggles to make sense of these changes. This will result in the brain actively searching for a threat where one might not even exist and this results in increased anxiety.

Physical Changes Of Fight-or-Flight Explained

woman looking at a glass with the word "change" in the background

Now let’s dig in and look at all the changes that happen in the body when you are anxious, stressed, or feeling panicked. The key is to remember that the fight-or-flight response is meant to protect you, not harm you. So, let's dive in a little deeper and have a look at exactly why all these physical changes happen.

  • Breathing becomes quicker and shallower

When anxiety hits, one of the earliest changes that people notice is that their breathing changes. Breathing tends to become quicker and shallower. Why, you may ask. Quicker breathing allows your lungs to take in more oxygen. Oxygen is so very important because it gives your muscles power and strength.

  • Increased heart rate

Another early change which occurs when we are stressed is that our heart rate increases. Your heart receives the oxygenated blood and disperses it to the different muscles in your body. When your heart rate increases during the fight-or-flight response, your heart is working overtime to make sure the blood gets to important muscles in your body, such as your thighs and biceps. This helps you to be faster and stronger.

  • Dizziness or lightheadedness

Dizziness and/or lightheadedness are the result of the extra oxygen that has accumulated in your body. If you don’t use the oxygen by either running away or fighting, it throws things off.

  • Tingling or numbness in fingers and toes

Tingling or numbness in your extremities is the result of your blood flow being redirected to more important body parts. Simply put, in a life or death situation, your toes and fingers will be of minimal use.

  • Vision changes

Another change that happens during the fight-or-flight response is that your pupils dilate. This occurs in order to help you focus on the threat. You may notice that you develop tunnel vision and that objects which are not straight ahead of you, may appear blurred. The reason for this is that if you have a bear right in front of you, you want to focus on its every move.

  • Hearing becomes more acute

In order to compensate for the changes to vision, hearing will become more sensitive. The goal is to help you determine if another threat might be approaching you from one of your sides or behind.

  • Dry mouth and bladder issues

If you are being chased by a bear, the last thing your body needs is to expend energy on digesting your lunch. So another change that happens when we are faced with a threat is that energy is reallocated to more important systems in our body. Your digestive system is not necessary for survival and so less energy is directed there. This will result in stomach upset, frequent urination, nausea, and a dry mouth.

  • Muscle tension

The whole goal of the fight-or-flight response is to make you faster and stronger. So your muscles respond by tensing up. This is your body getting ready to spring into action.

  • Sweating

All the changes noted above take a lot of energy and increase your body’s temperature. In order to stay cool and prevent overheating, we sweat. This is how we regulate our temperature.

  • Thoughts racing

Last but not least, one of the final changes which occurs during the fight-or-flight response is that our mind goes into overdrive. This helps us to evaluate the threat and make quick decisions to help assure our safety. It can be hard to focus on anything else. We can start ruminating and overthinking things.

Deep Breathing With A Twist

Now that you know why these physical changes happen and that their primary goal is to keep you safe, as promised, here is a strategy to help slow this response down.

One of the quickest and easiest ways to decrease anxiety is to engage in deep breathing. Deep breathing is easy and effective. It can be done anywhere and you don’t need anything fancy to do it. The best part… others will not even realize you are doing it.

Sit up straight. Put a hand on your stomach and a hand on your chest. Take a deep breath in - the hand on your stomach should move. This is a sign that you have engaged your diaphragm, one of the muscles responsible for breathing. Now take another shorter breath - the hand on your chest should now move. This is a sign that you have used your chest muscles, another muscle group responsible for breathing. Now hold for 2 to 3 seconds and breathe out. Repeat this process for 2 to 5 minutes. Easy peasy!!

5-minutes breathing technique consisting of 4 steps

You may be wondering why you need to take two breaths in for every breath out. The answer is simple - we do not breathe like this naturally. Therefore, it will take a conscious effort on your part and you will be going against your natural instinct. This will help you to focus on the breath, which can be grounding. It will also keep you distracted, because you will consciously have to think about breathing.

Closing Words

The physical changes of the fight-or-flight response are adaptive and helpful from a survival standpoint. They all have a specific purpose and role in keeping you safe. My biggest recommendation is for you to try and normalize what is happening in the body when you are anxious, stressed, or feeling panicked.

During moments of anxiety, stress or panic remind yourself of the purpose of the physical changes: “They are here to keep me safe and they will not harm me.” Sometimes our fight-or-flight system is triggered by psychological stress, as opposed to a physical threat, and we cannot simply run or fight our way out of this situation.

Call our clinic today at 613-877-4148 to connect with a trained professional, who can help you navigate the healing and recovery process.

Jessica Lankmann bio on Limestone Clinic

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