Why is exercise good for stress

​Why is exercise good for stress?
 
Rather than talking and giving reasons why exercise is good for stress, I think a closer look into what actually happens to the body to cope with stress is really important; to humans stress has always been a part of our lives and going back to caveman time’s stressful situations would inevitably have occurred. Stressors in the modern world come in different forms than that of the cavemen but there certainly are plenty of stressors out there!
 
The body’s nervous system is responsible for sensing, interpreting and creating an action throughout the body. The nervous system will be the body’s first response to stress; a division of the nervous system is called the autonomic division. The autonomic nervous system is the controller of the organs and glands of the body and can be broken down to the sympathetic and parasympathetic division. This is really important to our understanding of stress; the sympathetic division is called the flight or fight response and will speed up the heart rate and prepare us for stress but on the other hand the parasympathetic division slows things down and is known as the rest and repair system.
 
Therefore it makes sense we need both systems to work but if the balance is out of equilibrium and we are spending a high percentage of time in the fight or flight system this will have adverse effects on our body, one of which is not allowing time for repair. So in essence for the body to be healthy spending more time in rest and repair state (parasympathetic) would be a very good thing to be aware of.
 
The nervous system is able to deliver high speed signals throughout our body but the endocrine system works in response to the nervous system and uses glands to excrete hormones; these are chemical messengers released to create a certain action or response.  When the body is in fight or flight mode, a hormone called Cortisol is released, this hormone provides many positive functions in the body but a high level may well be problematic and can lead to poor digestion, elevated heart rate and blood pressure and can slow down metabolism, making it difficult to lose weight.
 
So why does exercise help?! Exercise will not only cause an increase in sympathetic activity during exercising but will also cause the parasympathetic system to take over after exercising, causing it to produce a calming effect and therefore reversing the effects of fight or flight. Hormones such as dopamine, endorphins and serotonin levels are also increased which are all ‘feel good’ motivating, happy hormones!