Stress, Our Friend

In the last post, I promised that I would provide a practical application to help you make sense out of the General Adaptation Syndrome. I'm going to begin with a little anatomy, and then tell the story about a man, a bear, and how stress can be our best friend.

Murray and Pizzorno, in their book The Encyclopedia of Natural Medicine, give us a little anatomy primer on what is responsible for the cascade of events known as the stress response. The authors tell us that an area in the brain known as the hypothalamus serves as the gateway between the nervous and the endocrine (hormonal) systems. When our bodies are subjected to stress the hypothalamus signals a gland known as the pituitary, to direct the adrenal glands (which sit on top of the kidneys) to release a hormone known as epinephrine (2012). Now let's see how this applies to the man and a bear.

 

 

 

 

Here we have a man by all accounts who is in deep, deep, trouble. So, how is his body going to help him get out of the precarious situation? This is where stress becomes our best friend. The man's brain recognizes that he is in a life-threatening situation and the hypothalamus is mobilized into action. The hypothalamus says to the pituitary gland "Oh, oh. You better tell the adrenals to let loose with some adrenaline otherwise this guy is going to be somebody's lunch!"

 

 

 

 

The pituitary gland then kicks the adrenals into action and epinephrine begins to flow into the bloodstream. His heart rate and force of contraction begin to increase and the blood is moved away from less vital organs such as the skin and the digestive system, and pushed up towards the heart and lungs (more vital to survival at this point). His breathing also begins to increase as a way of supplying more oxygen to the heart, brain, and "exercising" muscles (arms and legs).

Our friend here is only going to be able to keep up this pace so long before the muscles say "we need more help!" In order for muscles to move and function they need to be supplied with an energy source, and this is where the liver comes into play.  This vital organ stores excess glucose (sugar) until called for by the body. Glucose or simple sugar is the primary energy source used by working muscles.  During a stressful (bear-chasing) situation, the liver begins to flood the bloodstream with sugar that is quickly brought to the muscles by way of the increased heart rate and force of contraction.  The muscles are now happy because they can keep this man moving at a marathon pace to escape this predator.

Another byproduct of the stress response is that the digestive system is slowed down dramatically.  The process of digestion requires a tremendous amount of energy to complete its task.  However, during the flight response, the vital organs as I mentioned earlier borrow this energy from digestion in order to help the hunted escape the hunter.  I am sure you will agree with me that the man could care less at this point whether or not the hearty meal he ate about an hour ago gets properly digested. He will have plenty of time for that if he escapes the bear.

Not everyone in their lifetime will be chased by a wild animal. However, one may be faced with every day life- threatening situations. Over the years we have heard countless stories of a mother being able to lift a heavy object that has fallen on top of and trapped her child underneath, or a civilian having the strength to pull someone much bigger than himself from a burning car.   It is the stress reaction (our friend) that has enabled these heroic feats.  The heightened sense of awareness that allows us to quickly move out of the path of a speeding car is owed to the stress reaction.  In all of these cases the body responds in the same exact way as the man running away from the bear.

What has been described in today's post is known as the acute stress reaction which is very vital to our survival.  Take note of what happens to you the next time you walk around the corner and someone says "boo!" or suddenly have to slam on the brakes of your car in order to avoid an accident.  How does your body react?  Do you become more keenly aware of your surroundings?  Increased heart rate and breathing?  Let me know what you experience.  Oh, and here is one more activity that activates the acute stress response:

 

 

 

 

 

Exercise.     Until next time, stay happy, healthy, and avoid any angry bears.      Tim

 

 

Murray, M., and Pizzorno, J. (2012). The Encyclopedia of Natural Medicine (3rd ed.).  New York: Atria,  782.