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Why Inertial Exercise


Because without coordination there is no controlled motion.

Chris EverrIn motion, as in life, it’s not what you do, but rather how you do what you do.  How you do what you do is technique.  The techniques you employ in motion arise from your experience associated with that motion.  Experience revisited regularly becomes knowledge. You “just know” at what level you can do a task and at what level you can’t.  You don’t think about it; you “just know." In motion, knowledge is everything.


Motion knowledge comes from confidence of action.  If you “just know” your skill to perform a task is beyond your capability, your confidence to complete the task is low.  Unless circumstances are dire, you won’t even attempt the action.  Skill and confidence are directly related to action and vice versa.

Most human action consists of very complex robotics.  The condition of motor units, proprioceptors, fuel supplies, and connective tissue are continually monitored, recorded, and adjusted.  Each action taken is the result of a prepared and activated motor program that activates many motor units simultaneously at quite literally mind-boggling speed.  Speeds much faster than we can perform cognizant thought but not faster than we can monitor.  Each action is recorded and slightly modifies our experience of that action.  These motor programs are a database of comparisons to confirm the results of a motion.  The more experience we have with an action the more confidence we feel about that action.  Feelings are the memory of our confirmation of movement.


newtonIsaac Newton developed an idea that every action produced an opposite reaction.  He proposed that everything had mass and that everything had motion. He postulated that mass in motion continues in its relative motion unless a force acts upon it.  This property of mass to remain in motion he called “inertia”. Then he postulated that action required force, and that was what changed the motion of the inertial mass. When the motion of a mass was changed, he called the change in momentum produced by the force an “impulse”.  When we move, we continually change the momentum or our body with impulses.  We are taking action against inertia, and it is inertia that stimulates what we feel.  Hence, all of human motion is a form of inertial exercise.



energy expenditure chart

Consider the following chart:


This chart exhibits the hiking calorie expenditure for the average male carrying various loads in military knap sack configuration (Passmore, R.: Human Energy Expenditure, Physiological Reviews, 1955 vol.35, pp 801-875).  It is important to note that in the case of 0 to 70-pound loads when walking at 3.5 mph and less (standard hiking speed) the calorie expenditure is within 2 calories.  From 3 mph and slower the change in weight has little to do with the energy cost.  Apparently, the energy spent here is involved in horizontal motion (gravity free) and not vertical (gravity affected).  So, the work done here is involved with balance and propulsion.


Normally we don’t think much about balance and propulsion. Automatic motor programs control most of it.  But when we trip, we become very aware of where we are in space.  Our safe recovery depends on our ability to react to the new unexpected forces encountered


timing chart

A review of this chart demonstrates the timing of the various in-line processes involved with reaction process (Swink, J.R.: Intersensory comparisons o f reaction time using an electropulse tactile stimulus, Human Factors, 1966, vol. 8, no. 2, PP 143-145.).  Obviously, if we had to think about recovery, injury is a definite possibility without the presence of protective motor programs. 


As mentioned earlier, much of human motion is robotic.  The mechano-receptors of the human body are sensors for our inertial guidance system.  The body interprets the electrical signals from these mechanisms as position and motion.  It in turn responds with electrical signals to motor units which create some form of motion that again stimulate mechano-receptors in turn creating the afferent efferent neurological flow we call coordination


So, all of human motion is learning to control inertia.

Inertial Exercise is about training the body to create and control inertia.