Stress – The silent killer

This article is designed to give you a better understanding of how your body deals with and responds to stress.

The body is governed by our Autonomic Nervous System, this is our automatic, subconcious system which is working throughout the day, often without us really being aware of it.

This includes things like our heart muscle contracting to pump blood round the body as well as breathing, reproduction, fight or flight and rest or recovery responses. The basics of life that have pretty much stayed the same for hundreds of years!

The Autonomic Nervous system is divided into two parts: the ‘Parasympathetic’ and ‘Sympathetic’ nervous system.

PNS is responsible for our rest and recovery systems. This is activated when we are in a relaxed state and in relation to fitness it is the system that is absolutely crucial to be activated between training sessions to enable our body to recover and to ensure we don’t become overloaded with stressors.

The physiological effects of this are significant: a reduced heart rate, relaxation of musculature, maintenance work (the body starts to look after itself), reduction in systemic inflammation, increase in digestion of energy and also storage of energy. There is also an increase in release of sex hormones (testosterone/oestrogen) and hormone release throughout the day starts to fall in line with our circadian rhythm (another ancient bodily system essential for health).

SNS is our fight or flight system. This comes into play during a stressor and is historically  crucial to survival. Our bodies still behave in the same way now as they did then!

It was triggered as we hunted and killed animals, or defended ourselves/loved ones in dangerous situations and the physiological effects it had helped us to do this more effectively. It is not designed to be ‘on’ at all times and is only activated in times of emergency…..supposedly!

The physiological effects of this are increased heart rate and breathing rate, release of cortisol, reduced pain perception, increase in systemic tension, and a reduction of the repair processes.

Essentially, any non essential processes are put on hold – so staving off that cold, digesting that meal you just ate, immune system activity and sex drive are all put on hold.

Remember this is an ancient system and if you are fighting for your life or hunting that prey to stop your family starving and to ensure survival, you don’t have the energy/resources to be diverted to these other processes…..especially as you may never live to need to digest the food, have the sex or suffer the cold!! So, the body is smart and puts them on hold.

All of the above is dictated by the stressors that we as humans experience. These are what activate the SNS response. Without any stressors, we would be in a permanent state of rest/recovery and have a pretty chilled life! However, like all animals on this planet, stressors are a part of our life. So what is a stressor? We can divide them into three main groups:

Acute Physical Stress

 Life or death situation. You are a zebra and a lion is hunting you and you have to run – quick! Your house is on fire and you have to rescue your kids from inside. You have been confronted by a man with a knife in a dark alley – you need to fight hard or run quick!!

Chronic Physical Stress

You own a smallholding in central africa and famine strikes – 8 months of low food/water. Or, WW3 breaks out and we are forced into prolonged physical and mental stress as all that you know is broken down around you. Or, a hurricane strikes and all local amenities are destroyed and you are cut off from help for seven days.

Psychological/Social Crisis – Events generated by modern society in the main. Divorce, social media, body image, mortgage repayments, job losses, financial pressures, off the rails teenagers, drug/alcohol misuse, relationships, traffic jams etc.

If we look at these you can see that, as humans, most of us very rarely encounter the top two types of stress, this is just how we are designed to live. Extreme stress coming along very rarely. Even someone like a police officer or soldier only experiences extreme stress very rarely unless they are very unlucky (be aware that people in these professions may also have their perception of stress altered slightly). This is the same for most animals on this planet and it is how nature intended us to live.

However, for us as humans, we have created a world FULL of social and psychological stressors as listed above. These create exactly the same emotions and wild responses internally as fighting for our life in the wild would create. There are two main problems with this:

1 – We have no physical outlet for most of our modern stressors! Our body is ramped up to run or fight when we experience the stress of losing our job.

2 – These stressors are coming at us all from all directions, all the time!! This is when they become chronic and this is what leads to poor health and illness.

As the body is constantly dealing with these stressors that we experience (which are mostly in our minds) it is constantly putting off immune function, digestion, sex drive etc etc.

This is leading to and has been linked extensively to mid section fat gain, diabetes, heart disease, depression, suppressed immune function, decreased sex drive and disrupted menstrual cycles. All pretty serious issues…!

The problem is that we are in a stress filled world and it can be extremely difficult to remove these stressors without moving away to become a hermit! So how do we mitigate these problems?

Well there are a few things we can do. The main thing is to ensure that your PNS is activated as often as possible. Many of us have forgotten how to get ourselves out of fight or flight mode and back into rest and recovery mode! We need to incorporate activities that drive PNS activation.

Be mindful of the fact that exercise is also a stressor. It’s just that generally it is a good stressor, so don’t call training a ‘de stress’ tool as it isn’t. It will keep you healthier and help to use that stress response as we are designed too, but it does not count as a de stress tool! The reason you feel good after training is that you know it is the right thing to do and also endorphins are released during exercise…which is why it can become a tad addictive to!

Activating PNS:

1 – Light aerobic exercise. This could be a walk in the sun or on a fresh winter morning with loved ones. Or just an easy 30-40 minute cycle ride. This is NOT a tough met con or class!!

2 – Stretching. Spending some focused time doing some stretching or foam rolling will help to activate the PNS, as long as you are keeping it fairly gentle and not going into horrendously painful positions!

3 – Breathing. Spend some focused time (I like post training and pre bed) to do some breathing drills. Start with 3×10 breaths. Try 2-3s inhale and 6-8s exhale. Focus on letting your body relax with each breath, mentally relaxing your muscles and trying to be mindful of not dwelling on stressful life circumstances.

4 – Cold showers……seriously! These have worked a treat for me before bed and in the morning. They just take a while to get used too, slowly drop the temperature over a week or so until it is cold enough that it takes your breath away a bit.

Try to start incorporating some of these actions in to your day to day life and also being more mindful of getting stressed about the smaller thing in life. I have become a lot more ‘aware’ of what stresses me. Some I can control, some I can’t! I just try to control what I can and let more stuff ‘go’…..sometimes!!

The above is mostly aimed at helping you improve your health. However, if you are chasing improved performance within a given sport then you are most likely training very hard and in doing so, driving your SNS activation….a lot. Be sure to incorporate these ideas into your lifestyle to help your body adapt to the stress you are providing it with training.

Athletes that just follow the strategy of more training harder and harder and more and more will eventually see a decline in performance and in health. This is why elite athletes will have a good balance between tough training and ‘easy’ sessions. Both are absolutely essential for improving performance. The balance between providing enough of a stressor for your body to adapt to and enough PNS activation for your to facilitate that adaptation is where the magic to improved performance lies.

During competition, some athletes may find that SNS activation becomes overwhelming and nerves/anxiety lead to a drop in performance. Some of the above PNS activation could be implemented in competition settings to help with this.

Hopefully, this article has provided some basic knowledge around the subject of how our Autonomic Nervous System works and how it has an effect on our health and performance!




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