The Autonomic Nervous System: The body's accelerator and brake
What is the nervous system?
The nervous system is like the computer network of our body.
It is made up of over 100 billion...yes BILLION nerve cells that send and receive signals throughout the body.[i]
Two Types of Nervous Systems
There are two types of nervous systems in the body.
Photo by yodiyim/iStock / Getty Images
There are the nerves that controls we have control over. Like moving our heads, arms legs etc. This system is called the voluntary (somatic) nervous system.
The second type is the involuntary (vegetative or automatic/autonomous) nervous system (ANS). As you can imagine, this system is responsive for the things that we can’t control. There are things you can’t control, you ask?! These are the things that tend to keep us alive but we fortunately do not have to control. Like the beating of our heart, the digestion of food etc.
The Accelerator and the Brake
This ANS also has two subsystems that oppose each other.
The Accelerator - Look out, it’s a LION!
The first is our sympathetic nervous system (SNS).
This is our accelerator. Our GO GO GO!!!...system. Aka our ‘fight or flight’ system.
Picture walking across the African plains and seeing a lion in the distance.
First step…swear (F*#K!).
Next step…fight or flight.
You could either fight the lion or get the hell out of there quick smart (flight)!
Imagine what would help you to do those things.
You’d want to have energy in our muscles to fight or runway.
Sounds like a good plan, right?
To do this, your SNS reacts to a threat by increasing your heart rate, widening your airways, releasing stored energy and increasing the strength in the muscles.[ii]
What don’t you need? To digest the food you just ate. SO your digestion slows and other less important bodily processes are also slowed.
The Brake - Time to relax
The second is our parasympathetic nervous system (PNS).
This is our brake. Or our ‘rest and digest’ system.
This is what our body does when it doesn’t think we need to fight or run away from a lion.
Why do I care?
Well, in today’s modern Savanah, our nervous system does not seem to know the difference between everyday stress and the lion.
So that work deadline, that overdue bill and that fight with our partner all register as a lion and our SNS prepares to fight or run away.
The difference is, when we used to react to a lion, it was short lived. We either succeeded in fighting the lion or running away, or we…well…didn’t. Either, it was all over in a relatively short amount of time.
However, now-a-days, the threat can be almost constant and the SNS is triggering the fight or flight response for very long periods of time causing us harm including digestive problems, anxiety, sleep problems, memory and concentration issues, depression and many other issues.[iii]
Essentially, we are running around with the accelerator stuck on.
Hence the term, frayed nerves, I guess. No wonder we are exhausted!
What can I do?
Meditation has been found to decrease the SNS (let go of the accelerator) and increase the PNS (apply the brakes) resulting in decreased heart rate, blood pressure, stress hormones and muscle tension.[iv]
Yoga has also been found to reduce the SNS (let go of the accelerator), reducing stress hormones.[v]
Exercise has also been found to increase the PNS (apply the brakes).[vi]
Conclusion
The autonomous nervous system is the part of our body’s computer network that we can’t consciously control. The SNS is our accelerator and was originally responsible for reacting to threats such as lions. These threats were often temporary and the reaction to fight or flight was only needed for short amounts of time. However, the nervous system treats today’s modern threats of stress the same way leaving us with our accelerator left jammed on. This can cause many health issues such as sleep problems, memory issues, anxiety and depression. Exercise, yoga and meditation have all been found to reduce stress by releasing the accelerator and applying the brakes.
Apply the brakes through exercise, yoga and meditation at Recharge.
[i] https://www.healthline.com/health/fun-facts-about-the-nervous-system#1
[ii] https://www.medicalnewstoday.com/articles/327450#factors-that-affect-how-it-works
[iii] https://www.heart.org/en/healthy-living/healthy-lifestyle/stress-management/lower-stress-how-does-stress-affect-the-body
[iv] Benson, 2000; Calson et al., 2007; de la Feunte, Franco & Salavator, 2010; Lazar et al., 2005; Zeidan, Johnson, Gordon & Goolasian; all cited in: Hölzel, B. K., Lazar, S. W., Gard, T., Schuman-Olivier, Z., Vago, D. R., & Ott, U. (2011). How does mindfulness meditation work? Proposing mechanisms of action from a conceptual and neural perspective. Perspectives on psychological science, 6(6), 537-559.
[v] Ross, A., & Thomas, S. (2010). The health benefits of yoga and exercise: a review of comparison studies. The journal of alternative and complementary medicine, 16(1), 3-12.
[vi] Hackney, A. C. (2006). Stress and the neuroendocrine system: the role of exercise as a stressor and modifier of stress. Expert review of endocrinology & metabolism, 1(6), 783-792.
