| An example of the functional power of The IMP can be seen in the following research example:
A high tech neutrachemical corporation was seeking to measure the efficacy of its products with competition karate athletes. Because this study
 measured repetitious striking, an instrument capable of operating in the time frames of functional striking motion was needed. The measurement of the striking forces would need to be as non-evasive as possible. Test subjects would need to be free of obstructions in order to maximize fluid controlled strikes.
High acceleration activities such as striking or throwing frequently occur with joints moving at 500 degrees per second and higher with significant force generation occurring in less than 30 milliseconds. Accurately capturing the forces produced in the striking action required selecting instruments which could sample in the 2,000hz time frame. These sample rates would acquire over 90,000 samples per subject and therefore require computer software for analysis.
An Inertial Exercise Trainer, (figure 1) fitted with The IMP, was utilized to collect the many instantaneous forces produced by the test subjects. The Inertial Exercise Trainer uses the acceleration and deceleration of mass (weight) as its exclusive resistive medium. The system is designed so that during the exercise process a minimal amount of resistive friction exists in the instrument. Resistive loads caused by gravity are nonexistent within the system. Therefore, the muscles being exercised are concerned only with coordinated acceleration and deceleration of mass.
The instrument operates in the following way: When pulling on an extremely low stretch line, a travel platform accelerates down guide rails. At the center of the device the accelerated mass of the platform (plus any weight on the platform) possesses inertia and will continue to travel down the guide rails. Pulleys at the center of the device cause the pull line to reverse its line of travel. The pull line then exerts a force, the sum of the inertia of the platform, on the operator. The operator must then decelerate the mass. When this deceleration phase is completed the travel platform is, by the series elastic nature of muscle in tension, transitioned into another acceleration cycle. The inertial force produced is directly proportional to the acceleration imposed on the travel platform. Therefore all the forces produced are exclusively energy generated by the user.
Previous experience with the Inertial Exercise Trainer indicated users would maximize their force output capabilities while bringing on quick fatigue. Further, it has been demonstrated that users generate their highest forces, with inertial exercise, when utilizing phasic muscle contraction. Quick fatigue and rapid phasic muscle contraction are associated with anaerobic activity.
 A non-evasive method of collecting the forces produced by the subjects is accomplished by placing an analogue force link between the frame and a pulley within the natural line travel (figure 2 & 3) of the instrument. The voltage from the force link is converted to digital input for (figure 4) computer analysis. Analogue to digital conversion is sampled here at a 2,000 Hz rate and analyzed through the use of software from DATAQ instruments. Calibration of the test instruments find the measurement system accurate within .10 pounds at loads of 5 pounds and greater in sample times of 100 ms and less per event (strike). Data is then converted to a 1000 Hz sample rate for analysis.
The testing parameters specify three 15 second intense exercise bouts with resting periods of 30 seconds between each bout. The IMP records the force activity during the rest periods as well as during exercise. . It is considered extremely important to standardize the queuing for exercise of each subject. A computer automated audiovisual timing program was developed and incorporated as a standard control mechanism to be used with each subject. The program displays a visual message while simultaneously producing an auditory stimulus. A computer screen placed directly in front of the test subjects allows viewing of the commands. The timing program sequence is as follows:
A six-second Prepare for Exercise message introduced by the sound of chimes.
A four second Get Set warning accompanied by drum roll
A fifteen-second Go Go Go message introduced by the sound of a gun shooting.
A three-second Stop message introduced by the sound of a ricochet.
A seventeen second Rest message introduced by a clapping of hands sound.
A loop back to the six second Prepare for Exercise.
At the end of the third Go Go Go period the Stop sequence transitioned to a That’s All message introduced by the sound of clapping hands.
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