Stress, Cortisol, Its Impact on the Body & Management

Living in a faster paced world and modern day pressures has meant that stress is an inevitable part of our everyday life. According to the Mental Health Foundation, an average of 37.1% of women and 29.9% of men in the UK report high levels of anxiety in 2022/23 (4). Anxiety can lead to stress and affect the sympatho-adreno-medullary (or SAM) system which is our body's coping mechanism in stressful situations. In addition, anxiety can cause mental, emotional, behavioural and health problems (8).

This post will delve into the physiological affects of chronic stress on the body, how the mind responds to stress anatomically and what can be done to help improve the wellbeing of our mind in times of perceived stressful situations. 

Cortisol
Cortisol is a glucocorticoid hormone produced by the adrenal glands located at the top of the kidneys and is important for numerous physiological processes (Figure 1). It governs our circadian rhythm (or 24 hour clock), activates the complex hypothalamic–pituitary–adrenal (HPA) axis, our body's natural response to stress, and maintains the body's homeostasis (3).

Cortisol is the body’s primary stress hormone and can be linked to weight gain due to its ability to trigger metabolic changes to promote fat storage thus hinder weight loss, increase our appetite, reduce metabolism, promote muscle breakdown and alter our fat storage (3). Thus, disruptions in cortisol regulation due to chronic stress can cause chronic related disease and ageing and can have profound implications for multiple bodily systems (3).

The Role of Cortisol
Overall, cortisol is a vital catabolic hormone produced by the adrenal cortex of the kidneys. It is released in a diurnal fashion i.e. it is released throughout the day, with blood levels peaking in the morning to facilitate arousal and steadily declines thereafter. During the day, cortisol maintains blood glucose and suppresses non-vital organ systems to provide energy to actively function the brain and neuromuscular system (1). Cortisol is also a potent anti-inflammatory hormone as it prevents widespread tissue and nerve damage associated with inflammation (1).

The SAM system allows the hypothalamus in the brain to activate the sympathetic branch of the ANS which then signals the adrenal medulla to secrete adrenaline and noradrenaline (figure 2). This allows the body to get ready for either a fight or flight response, can lead to sweating, hyperventilation, increased pulse rate and blood pressure (8). 

The hypothalamic–pituitary–adrenal (HPA) axis controls the body's response to stress and regulates the release of glucocorticoid (GCs) (Figure 2.) (7). The down side of the HPA axis is that it can become increasingly desensitised over a period of time as prolonged cortisol release causes chronic stress to exert ill effects on the body.

Red Flags & Referral:
During consultations and prior to initiating treatment, physical therapists are trained to identify 'red flags' which warrant referral symptoms of non musculoskeletal origin and identify symptoms that cannot be treated via physical therapy (e.g., visceral pain, saddle anaesthesia or night pain) (1). Thus highlighting the importance of the case history stage as it provides therapists time to comprehend whether or not a patient is suitable for treatment. 

Yellow Flags:
Identifying 'yellow flags' help warn clinicians a probability that treatment might be complicated by psychological variables such as fear, anxiety, catastrophising behaviours and that a prognosis might fair. With a UK population struggling with an increased problem of anxiety in everyday life, physical therapists are becoming increasingly proficient in the identification and treatment of yellow flags (1). According to a report focused on wellbeing by the Office National Statistics (ONS), it has been reported that one in 17 people in the UK have low life satisfaction and almost a quarter have high levels of anxiety (5). 

The Sympathetic Nervous System (SNS) & Parasympathetic Nervous System (PSNS)
1. The Sympathetic Nervous System is a network of nerves that helps your body activate a “fight-or-flight” response and increases with heightened stressed, a feeling of danger or during physical activity. The SNS promotes catabolic tissue breakdown and the metabolism of fat which mobilises glucose energy for energy and promotes arousal, alertness, motivation and goal directed behaviour (1).

2. The Parasympathetic Nervous System (PSNS) - What Therapists Try To Encourage! This system helps promote HEALING, repair, immunity and the anabolic growth required for restored energy reserves. Needless to say, a delicate balance between sympathetic and parasympathetic activity is critical for long-term physical and psychological wellbeing (1).

One of the proposed mechanisms is that constant Glucocorticoid (GC) release caused via chronic stress can overtime blunt the hypothalamic–pituitary–adrenal (HPA) axis response. This can lead to HPA axis dysregulation and cortisol resistance. In chronic scenarios, the release of glucocorticoids can contribute to various neurological disorders including Alzheimer's disease (AD), Parkinson's disease and depression (7).

Chronic stress triggers prolonged HPA axis activation, resulting in elevated cortisol levels, which can lead to hippocampal (responsible for learning and memory) atrophy in the brain, synaptic dysfunction, and neuroinflammation which is recognised as a key pathological feature of AD. These alterations can impair cognitive function and may exacerbate amyloid-beta plaque formation which is the pathological hallmark of AD (7). Concurrently, persistent cortisol elevation affects the prefrontal cortex and limbic structures, contributing to depressive symptoms (7). The interplay between chronic stress, HPA axis dysregulation, and neuroinflammation (tissus within the brain or spinal cord) is important for understanding the comorbidity and presence of AD and depression.

According to Professor Steven Peters; the author of the 'Chimp Paradox', the mind can be divided into three parts; the Human, the Chimp, and the Computer. The Human is the logical and rational thinker; the Chimp is the emotional, impulsive being and the computer stores our beliefs and past experiences (6).

Just like the body, everybody's mind, how it thinks and copes or reacts to different situations is unique. Developing a deeper understanding of the mind, how our thought processes work and the options available to us for how to manage our thoughts can develop coping strategies that best suit us.

The Chimp Paradox is designed to try and help us to adopt a strategy that aims to slow our thought process and reactions down and think in a more calmer, logical manner. For instance,  a British politician says something that triggers you to feel irritated by saying e.g. we now must pay higher taxes or bills. According to the Chimp Paradox the information processed goes like the sequence below (6): 

1. The new (irritating) information is first processed to the amygdala - a fast acting defence mechanism that responds quickly and the chief emotional centre in the limbic system or your 'chimp'. The 'chimp' tends to overreact and makes us respond via impulse i.e. anger or outburst with irrational behaviour. 
2. The next centre of the brain your the information to be processed is the orbito-frontal cortex which is at the outer edge of the frontal lobe and tries to control impulses and uses moral judgement e.g. to not instantly swear or shout at the politician's remark. 
3. Next, provides us with another moral guide and a conscience of guilt - the uncinate fasciculus within the limbic system e.g. that swearing is perhaps not a good idea in this instance and try to think of a way that might resolve the problem. 
4. A part of the frontal lobe that works analytically and logical thought is the next stage with the use of the dorso-lateral pre-frontal cortex  (DLPFC) e.g. you might think another way of how to improve the economy than the politician's proposed increase of taxes or bills. 
5. The fifth stage allows us to be more considerate and empathise for others' feelings, this happens within the ventro-medial pre-frontal cortex - i.e. one may think about whether the politician has a point (or not) but explain why in a logical and controlled way, you might then EMPATHISE for other people being told the same information as you.  
6. Lastly, is the cingulate cortex within the limbic system which is the decision making process that is influenced via past experiences e.g. you might decide that the politician is wrong to increase taxes as past experience has taught you that this is not good for the economy.

This processing of information all happens within a split second, especially when processed to the amygdala and everyone's 'chimp' differs in strength. The stronger the 'chimp', the more work required to reason with it and prof Steve Peter's book provides different solutions with how to go about doing this.

The mind, how it processes thoughts and information should be thought as like a muscle with that it takes training, practise and patience to help develop a healthier way of thinking. The chimp paradox also explains how we all have a responsibility to manage our 'chimp' and good management can stop it from making us feel bad, do or say something that we might regret and prevent harm to others. Managing the Chimp is a skill, it takes time and practise to deal with emotions and impulses (6).

Failure & Setbacks
The Chimp Paradox explains that 'fear of failure' or setbacks need to be seen as challenges or an opportunity to further develop ourselves and improve the skill of problem-solving. When we fail at something, the chimp tends to see this as a catastrophic event and typically blows everything out of perspective which will have an impact on our self-esteem and self-worth. On the other hand, humans see failure as an opportunity to iprove skills, develop as a person and accept that sometimes we don’t win or always get everything right (6). 

The Mental Health Foundation provide a good list and steps for helping  us to lift our mood (4):

• Talk: talking to friends or peers whom you can TRUST can help the feeling of being less alone. Talking can help you feel comforted, gain a different perspective and that your thoughts can be shared and discussed.
• Diet: Reduce or cut down the intake of a diet high in sugar or salt and plan meals ahead for a structured, wellbalanced diet. 
• Physical Activity and Boost Endorphins: Endorphins are natural hormones produced that help us to feel good. Become committed to an activity that you enjoy and CAN regularly do; regularly attending classes or an activity with others is a great way to meet new people e.g. tennis, aerobics, walking groups, book clubs, arts and crafts clubs, volunteer for a charity.
• Get Out Into Nature: A GREEN environment can help reset the mind, improve our concentration, feel happier, help spiritual wellbeing and make us realise that there is a 'bigger world' outside of our own. 
• Avoid cigarettes and alcohol: They can feel good initially, but make make things worse in the long run, especially if in a low mood - try to avoid these things if mentally in a low mood. 
• Educate Yourself - You Are Your Own Best Therapist - There is a lot of help out there: Meditation, Go on YoTube and listen to hundreds upon thousands of therapists for mental health and depression including Paul McKenna or Gabor Mate for FREE! LEARN ideologies such as Reiki, chakras, yoga and pilates, reading or audio books such as the Chimp Paradox.
• Write a Diary: Write down when you last felt low or irritated. How long did it last? How did you make yourself feel better? Could you think in a different way next time for if a similar trigger reoccurs? Could you have reacted differently? What could you do differently as a reaction next time? Were you tired, overworked or lacked sleep before hearing the trigger? Sometimes it is better to not react initially, collect your thoughts first and then come back with a response that is not based on an impulse? 
• You Are Not Alone: Everyone goes through ups and downs and has to find ways to help manage their 'chimp'/ mind or  mental wellbeing in all situations. What makes one person different to another is HOW they deal or react to a situation that they are presented with. Mind management is a long term skill to be constantly trained and learned - you are very much NOT alone. 
• Talking Therapies/ Therapies: Talking therapy or counselling, cognitive behavioural therapy (CBT), hypnotherapy, Neuro-Linguistic Programming Therapy (NLP) - there are conferences that can be attended for free.

Subramanium et al., (2019) found 16 studies supporting the conclusion that massage therapy can be an effective treatment to reduce anxiety. They found that massage can help relieve a person from discomfort and provide physical and psychological benefits (8). 

1. Hannibal, K. E., Bishop, M. D. (2014) Chronic Stress, Cortisol Dysfunction, and Pain: A Psychoneuroendocrine Rationale for Stress Management in Pain Rehabilitation, Physical Therapy, Perspective, 94;12: 1-10. 


2. Knezevic, E., Nenic, K., Milanovic, V., Knezev, N. N. (2023) The Role of Cortisol in Chronic Stress, Neurodegenerative Diseases, and Psychological Disorders, MDPI, Cells, 12; 2726: 1-18. 

3. Maurya, N. K. (2024) The Cortisol Connection: Weight Gain and Stress Hormones: Review Article, Archives of Pharmacy and Pharmaceutical Sciences, HSPI - the Open Access Publisher, 2639-992x: 9-13.


4.Mind, Mental Health Foundation (2023) Office of National Statistics, NHS, WHO, Children's Commissioner for England; https://www.mentalhealth.org.uk/explore-mental-health/statistics/anxiety-statistics [Online] Last visited 20/03/2025. 


5. ONS (2024) Measuring progress, well-being and beyond GDP in the UK: May 2024 - Exploring quality of life in the UK, drawing on the latest economic, environmental and social statistics. This quarter we focus on the quality of life of individuals, file:///Users/joey/Downloads/Measuring%20progress,%20well-being%20and%20beyond%20GDP%20in%20the%20UK%20May%202024.pdf [Online] Last visited 15/03/2025]. 


6.Peters, S. (2012) The Chimp Paradox [1st Ed.], Vermilion; London. 


7. Sharan, P., Vellapandian, C. (2024) Hypothalamic-Pituitary-Adrenal (HPA) Axis: Unveiling the Potential Mechanisms Involved in Stress-Induced Alzheimer’s Disease and Depression, Cureus, 16; 8: 1-11. 

8. Subramaniam, S., Latip, H. F. M., Aziz, M. S. A. (2019) Massage Therapy for Anxiety Reduction: A Systematic Review, Sryahwa, Journal of Sports and Games, 1;  2:13-17.