The clinical utility of force/displacement analysis of muscle testing in applied kinesiology.

Manual muscle testing procedures are the subject of a force and displacement analysis. Equipment was fabricated, tested, and employed to gather force, displacement, and time data for examining muscle test parameters as practiced by applied kinesiology (A.K.) clinicians. Simple mathematical procedures are used to process the data in an effort to find potential patterns of force and displacement which would correspond to the testing of strong and weak muscles on healthy subjects. Particular attention is paid to the leading edge of the force pulses, as most clinicians report that they derive most of their assessment from the initial thrust imparted on the patient's limb. An analysis of the simple linear regression of the slope of the leading edge of a force pulse reveals that a high dx/dF is indicative of a weak muscle test result (as perceived by the tester), and a low dx/dF is indicative of a strong muscle test. Thresholds for dx/dF are determined to discriminate between inhibited and facilitated muscle test results. The data lay the groundwork for future studies that examine the objectivity of A.K. muscle testing.