The autonomic nervous system regulates the functions of our body as situations so require. Recovery and healing systems are the most active during sleep. After lunch it is important to digest the food and use the nutrients efficiently. When faced with imminent threat, the immune system and food processing are not important. These functions are turned off to conserve all possible energy for the use of muscles, which are needed in the fight-or-flight response.
By and large, the autonomic nervous system works unconsciously. It is responsible for many vital functions such as blood pressure, temperature regulation, digestion, and function of the adrenal cortex. It works through the neural network that controls the heart and other organs. The autonomic nervous system keeps us alive without us knowingly doing anything about it.
The autonomic nervous system consists of two complementary parts, the sympathetic and parasympathetic. When active, the parasympathetic nervous system slows down our heartbeat, enhancing digestion and healing. It strives to calm the body down and keep the vital functions stable.
The sympathetic part is responsible for preparing our body for action, with the axons (nerve fibers) of the system being able to innervate tissues in almost every organ. The sympathetic nervous system becomes active in stressful situations and during hard physical strain.
Both parts of the autonomic nervous systems normally work in good cooperation, but as a seesaw. When the other becomes active, the other slows down. For instance, in acute stress reaction the sympathetic nervous system works at full speed, in an instant. The parasympathetic part ceases to operate and, for example, digestion almost comes to a halt. The sympathetic and parasympathetic systems have evolved to enable accurate and fast regulation of our internal mechanisms, regardless of the situation.
The fight-or-flight response is a way for us to cope in a threatening, rapidly escalating situation. In the time of cavemen, situations requiring response were normally quickly over and fights did not last for weeks or months. For us today, things can be completely different: The stress reaction might be a permanent state, and the parasympathetic nervous system does not have the chance to return our body to rest.
In long term stress the cortisol levels in our body are continuously high
Chronic stress keeps the hypothalamic-pituitary-adrenal axis active. It is like an idling motor, pumping stress hormones, such as cortisol, to our system.
Cortisol helps us to confront the threat, but it simultaneously shuts down the immune system. From the evolutionary point of view, this makes sense: If a crocodile attacks, we can shut down all the functions in the body that are not essential for fleeing or fighting. The immune defense of our body is weakened when we are continuously stressed, and this might lead to a series of infections. Stress factors also play a role in the development of autoimmune diseases, heart and blood vessel diseases, and cancer. Continuous boosts of adrenaline can harm blood vessels, raise blood pressure and increase the risk of cardiovascular diseases.
Worrying and fear increase our mental load and can put further strain on the sympathetic nervous system; physical symptoms persist, recovery via beneficial rest and sleep does not happen.
Heavy cognitive and emotional load during recovery from an illness might be as bad for our body as physical exercise. Our body would choose to put the work aside when being ill.
Chronic Stress affects memory, concentration and appetite
In a state of chronic stress, the brain thinks that a physical fight is about to start at any time. Cortisol, in turn, tells our body to have much energy available. It then enhances appetite and storing of extra energy, with might lead to weight gain.
Cortisol is also released to the hippocampus, the part of our brain which is central for memorizing and learning. A stressed-out person has difficulties in learning and regulating their emotions. There are also often problems associated with concentration and memory.
Chronic stress cannot go on forever without its repercussions. Burnout is the consequence of chronic stress causing severe disturbance to our vital physical and mental mechanisms. A simultaneous collapse of our psychological, neural, metabolic and immune systems might be so all-encompassing that a complete recovery is very slow or even impossible.
The best cure for burnout is prevention. It can be difficult to accept the graveness of the situation. People tend to compare themselves and their work rhythms to others, set the bar too high and pretend that everything is fine. Just moments before the disintegration takes place, everything might appear quite normal for the people around.
Talk to your friends and family, colleagues, your superior or a health care professional if you feel that the load is too high. Usually the first cautionary signs are linked to changes in your sleep patterns.
The brain, sleep and stress
When our lives are in balance, we recover from acute stress reactions and even longer burdensome periods of strain. We all experience major turning points in our lives: a newcomer to the family, moving house, a study or work project that is exceptionally demanding. We overcome these changes and challenges when the quality and amount of recovery is sufficient enough.
Sleep is our most important means of recovery and an indicator of balance. Weeks and months of disturbed sleep is a sign of stress, and sleep deprivation further weakens our resilience to adapt to the challenges we have to deal with.
The brain needs sleep. During sleep our bodies repair and restore in ways we’re not aware of. It is almost like we need a nightly reboot to feel physically and mentally well.
There is no health without sleep. The importance of proper recovery becomes clear after experiencing periods of sleeping poorly. At worst life is reduced to mere coping. Unfortunately, this is reality for so many of us, so much so that we have begun to think it is normal not to sleep enough. But this couldn’t be further from the truth.
When we sleep well most nights and feel refreshed in the morning, our body and mind are better prepared to perform well. We are in balance.
The complete set of 5 articles explains the Moodmetric measurement, science behind and the applications:
- Part 1: Fight or flight response
- Part 2: Chronic stress – The brain concludes that we are continuously in danger
- Part 3: Tools for long term and continuous stress measurement
- Part 4: The Moodmetric ring stress measurement and understanding the data
- Part 5: The Moodmetric measurement in preventive occupational health