Muscle testing is also known as applied kinesiology (AK) or manual muscle testing (MMT). It is an alternative medicine practice that claims to effectively diagnose structural, muscular, chemical, and mental ailments.

Applied kinesiology (AK) is not a part of the science of kinesiology, which is the study of the movement of the human body.

The basic idea behind AK is similar to one of Sir Isaac Newton’s Laws of Motion, which states, “for every action in nature, there is an equal and opposite reaction.”

AK applies this concept to the human body. This means that any internal issues you may be experiencing would be accompanied by related muscle weakness.

Following this thought process, you should be able to perform a muscle test to diagnose any underlying medical condition. Muscle testing conducted in AK differs from standard orthopedic muscle testing.

Here’s an example: You have a muscle test performed, and your bicep is deemed “weak.” A person performing the muscle test following conventional medicine might suggest working out your biceps more at the gym.

A person following AK principles may suggest that you have this weakness because of an underlying problem with your spleen.

According to several studies — including a 2001 study on the kinesiology muscle test — some standard orthopedic or chiropractic muscle tests may be helpful for specific muscle-related weaknesses, but muscle tests are useless for diagnosing medical conditions (such as organic disease or mental illness).

However, a 2023 study found that the applied kinesiology muscle test provided accurate results when used to measure sacroiliac dysfunction. The accuracy compared to other types of tests was found to be comparable, and further studies are recommended.

AK began with George Goodheart, Jr. in 1964 as a system of muscle testing and therapy.

Several years later, in a study conducted by Ray Hyman, a group of chiropractors wanted to demonstrate that they were able to tell the difference between subjects given good sugar (fructose) and bad sugar (glucose).

A drop of sugar water was placed on a test subject’s tongue. They then measured the strength of each test subject’s arms. The chiropractors anticipated being able to identify which subject had been given the bad sugar based on their muscles being weaker. However, after multiple failed attempts, they ended the test.

More recently, these concepts have been debunked and described as “not conforming to scientific fact” regarding medical conditions and their causes or treatments.

Who practices applied kinesiology?

In a survey conducted by the National Board of Chiropractic Examiners (NBCE) in 1998, 43% of chiropractic offices in the United States used AK.

Although the majority of practitioners in the survey were chiropractors, occupations also included nutritionists, naturopathic doctors, and massage and physical therapists.

Currently, the Nambudripad Allergy Elimination Technique (NAET) advocates for the use of AK in treating allergies and other sensitivities.

However, the results of a 2001 study using muscle tests as an allergy test for wasp venom state that it is no more helpful in diagnosing allergies than random guessing.

Although AK has recently shown promise as a technique for diagnosing musculoskeletal disorders, the medical community has mostly rejected the idea of AK as a diagnostic tool for conditions in other systems of the body.

Until new research finds different results, it is not advised to put trust in this technique when making important healthcare decisions.