Stress, body composition and all things cortisol

08th June * 3 min read

Cortisol? What is it and how is it linked to stress? Does stress play a part in your body composition or has this ever even cost you a thought? Believe it or not, cortisol and stress can play a big part in your body composition…

Firstly, let us start by explaining what cortisol actually is. Cortisol is a hormone found in our bodies and it is released when we experience stress, exercise and even when you wake up in the morning. This is also the hormone triggered for the ‘fight or flight’ response also. Under events of stress, adrenal responses in the body are triggered. This fight or flight response causes glycogen in the liver to be released and muscle tissue are activated for use as a quick energy source. This uptake of energy was highly efficient in caveman days, while under attack from a tiger for example. Cavemen simply used this surge of energy to either run away or fight. The modern man is wired in the same fashion; however the difference is stress sources that plague modern life generally do not require running away or fighting. 

So, what happens when you’re stressed and your cortisol is high? It causes the body to flood it with glucose to supply energy for the ‘fight or flight’ and stops insulin from storing the glucose. Cortisol will also have an effect on the width of your arteries and causes an increase in your heart rate. According to a 2005 article from the University of New Mexico, this stress response can lead to loss of muscle mass, increased fat storage and impulses to overeat.

When your body is stressed, cortisol chooses the type of energy that you need – be it fats, protein or carbohydrates and how much you need to evade with the stressor. When this stress continues over a long period of time, this can then begin to have a negative impact on your immune system and its function, weight and/or weight gain and also an increased risk of chronic disease.

Stress can be often thought of as an excuse to eat, food cravings and overeating actually have a factual basis behind its effects. When a tense, stressful situation is over, the release of cortisol results in an increase of appetite. Under chronic stress, these cravings can lead to unwanted weight gain due to high level of cortisol release in the body.

Freeing your life from stress may seem like an impossible task, but you can eliminate unwelcome tension by applying a few techniques to your day. Identifying stress triggers in your life is the first step. By finding the root of your tension, it is easier to gain clarity on how to overcome them. If work is a cause, take five to ten minutes out of your day to meditate or practice deep breathing techniques to bring your body to a calmer state. Additionally, make time in your schedule for exercise. A routine exercise plan will decrease the risk of depression and assist in a better night’s sleep, which is a key factor in reducing cortisol release and weight gain. Interestingly, we have experienced some clients changing the timing of their own client’s exercise times from morning to evening to lower their cortisol resulting in a drop in body fat percentages. 

If you found this article interesting and helpful, you may also enjoy our previous blog – ‘The importance of sleep for fat loss

At FHQ we hope you enjoyed this fitness blog. Any feedback will be greatly received. For more information on our blogs or our qualifications, please call us FREE on 0800 112 3431.

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