What is a Muscle Test?

The Manual Muscle Test (MMT) was first described in the book Muscles, Testing, and Function in 1949 written by two physical therapists Kendall & Kendall.  MMT is an assessment of the body’s ability to maintain a contracted position against increasing applied pressure.  The muscle will either rate as facilitated (“strong”) if it can hold the position or inhibited (“weak”) if it breaks away.  Muscle testing is not unique to Applied Kinesiology.  It is a widely practiced diagnostic method used by medical doctors, physical therapists, and osteopaths.  Even the American Medical Association has accepted that the MMT is a reliable tool and advocates its use for the evaluation of disability impairments.  However, there is a difference in how a kinesiologist performs a MMT and how another professional performs a MMT, especially in terms of evaluation for disabilities.

Manual Muscle Testing is Functional Neurology.  This statement is based on the fact that it is the nervous system that sets the tone of the muscle and it is the nervous system that determines whether a muscle will test strong or weak.  A good example is showing how a muscle test will change depending on a patient’s standing posture. For an example of how the nervous system determines muscle testing findings please view video below about gait testing. The above example shows how a muscle can be strong one second and then when the body is placed in a certain position it will instantly change.  This has significant clinical ramifications.  During the evaluation process of a patient we are using history, posture, range of motion, palpation, and manual muscle testing to guide the appropriate treatment. The manual muscle test as a clinical tool has the following benefits:

  1. Patient complaints can have an objective basis. In addition to posture, range of motion, history, etc., the use of the MMT allows the practitioner to take a subjective complaint and apply some objectivity to it.  It gives the practitioner a road map to evaluate the patient’s complaint.
  2. Changes in the MMT can be observed instantly because we are evaluating the nervous system. The nervous system is one big electrical system.  Similar to when you turn on a light switch and you immediately see a room illuminate, when you activate the correct “neurological light switch” MMT changes will be observed instantaneously.
  3. The ability to maintain a treatment is measurable. After a treatment there should be a favorable muscle testing outcome, meaning muscles that tested weak should now be testing strong.  On the follow-up visit some of the muscle weaknesses may return and others may not.  The practitioner is able to tell where his treatment had a lasting effect.  In addition, the practitioner can determine if a similar treatment must be reapplied or if there is another factor influencing the muscle test.