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Comparison of Other Exercise Concepts vs Impulse Inertial Exercise


Obviously, when you compare one exercise device or concept to another, you are comparing apples to oranges. Many of these devices have the same “feel”, relative one to another, when the actual effects on the body produced by these devices are sometimes quite different. Understanding the feel of one type of exercise device, as its performance relates to another, may help the reader to understand the innate benefits derived from these devices.


What is felt, when using Inertial Exercise, is not necessarily what is actually attained.   The following oscilloscopic analysis of exercise with force transducer measurement may help to demonstrate.  Both force and accelerometry were measured simultaneously.  Force to demonstrate the way tension on the subject is imposed and accelerometry to show the pattern of control the subject imposes on the tension.

thera band chart

A subject was asked to perform three exercises, the first with Elastic Tubing (3/4 Theraband blue). The subject performed at what he considered a comfortable slow rate similar to what a patient might experience.


Body mechanics are external rotation of the shoulder, shoulder in neutral elbow at 90 degrees and about 45 degrees of external rotation. 


This force waveform is totally dependent on the elasticity of the tube. Some force is always applied.  Maximum force per repetition is about 6.5 pounds. Each repetition is about 1.748 seconds with maximal force done in about 884ms.  Note the erratic pattern of the accleleronetry.



tonic iet wave form

After the Elastic Tubing exercise, the subject was asked to perform Inertial Exercise using the tonic technique with 17.5 pounds on the sled.  He was asked to apply approximately the same force and feel as was applied to the Elastic Tubing.


This force waveform is dependent on the acceleration rate of the weight on the sled (mass).    Maximum force per repetition is also about 6.5 pounds. Each repetition is about 1.66 seconds with maximal force done in about 828ms.  So the timing is almost identical to the elastic tubing.  But, the shape of the force curve and accelerometry are entirely different than the tonic example.  Apparently, more is going on in the control of the acceleration and deceleration than the subject can feel.  This is functional co-ordination.  Note the smooth control of the accelerometry and its rhythmic relationship to the forces generated.

The third exercise was performed with Inertial Exercise using the phasic technique with 17.5 pounds on the sled.  Again, the subject was asked to apply approximately the same force “feel” as with the previously performed exercises.  The results were not what the subject expected.

phasic inertial exercise


This force waveform is dependent on the control of the reflex catch mechanism versus the attack velocity of the sled weigh (mass) from the previous repetitionForce per repetition is about 18 pounds with each repetition at about 360ms.  However, maximal force is done in about 56ms.  A time frame that is possibly less than conscious thought can control.   The subject was attempting to produce the feel of about 6 pounds of force or what he experienced with the tonic exercise.  In fact, almost three times that force was produced. Note the smooth control of the accelerometry and its rhythmic relationship to the forces generated.




wall pulley wave formCompare the waveforms of phasic Inertial Exercise with this example of the same motion performed on a wall pulley weight stack machine.


 The force is governed by the intensity of the exercise versus the effects of gravity on the 10-pound weight.  However, once the force exceeds 10 pounds the weight begins to accelerate vertically. Force per repetition is about 14 pounds with each repetition at about 1.45 seconds.  However, maximal force is done in about 280ms. Here also, there is a rhythmic relationship between accelerometry and the forces produced. 


Rubber tubing and weight stack equipment have a similar goal in that they are generally used for developing strength.  The accelerometry of each device indicates greater motor program control with the weight stack than the elastic tubing.  The wave analysis of the Inertial Exercise examples demonstrates similar or superior forces than those exhibited in the elastic band or pulley system.  These forces were created in much less time with less apparent control variance. 


The greater forces are a result of functional coordination as is the lower control variance.  Functional control requires the development of motor programs that maximize the efficiency of motor units performing a task.  This requires anticipatory timing.  Training anticipatory timing is what Inertial Exercise is all about.

Real Time Events

In the real world, many of the forces we generate (when we are in control of our motion) are so natural and occur so fast that we don’t appreciate their significance.  The following are samples of measurements of activities we do every day.  The significant number is the time it takes to generate the force.  In the real world, if we are unable to generate this kind of force in this time frame, no work will be done.


5 pound grocery bag

15lb grocery bag


At the left is picking up a plastic 5-pound grocery bag off of the floor. It's 38 ms from zero to peak force.


And at the right is picking up a 15-pound plastic grocery bag from the floor.  It's 86 ms to peak force in this example.





refrig door magnet

glass door

Look left and see what happens when you open the refrigerator door and the magnet seal strip finally let’s go.  The strip lets go here in 28-ms.


Ever had a heavy swinging glass door unexpectedly shut on you?  From the time contact is made with the door to control of the door is 58 ms.

In the case of the refrigerator door and the 5-pound grocery sack the peak force was created faster than neural processing is possible.  With the glass door and the 15-pound grocery sack, the timing was faster than reflex motor response was possible.  As each of these events and others occur in our lives, we respond with various times.  The important thing is that we have confidence to respond.  This confidence is due to our innate knowledge of how we are able to proprioceptively respond to actions in our realm of space.  Your level of performance is based on your confidence in your ability to respond reflexively.  Building motor programs, which confirm, in the body, an ability to react to forces and actions faster that conscious thought, is building confidence.  Maximizing the body’s awareness of its electro-mechanical capabilities is the goal of Inertial Exercise. 

After all, our bodies were made to control inertia, not to be its slave.