Resisted Tests

By Ben Benjamin, PhD

Question: A resisted test primarily tests which anatomical structures?

Answer: Muscles and tendons.

A resisted test places maximum stress on the muscle-tendon unit(s) primarily responsible for performing a particular movement or action.

Resisted medial rotation at 90 degrees. A resisted test is an excellent assessment tool for locating and identifying an injury. It is essentially an isometric exercise, generally performed in the mid-range of the muscle's action. This positioning enables the muscle to perform at maximum strength. When a resisted test is performed, the body part you are testing remains stationary. If the test is positive, the muscle-tendon unit will be painful while engaged in the resisted action.

For instance, resisted medial rotation of the upper arm will reveal if the subscapularis muscle-tendon unit is injured.

Resisted medial rotation with the muscle in a stretched position. As with all active and resisted movements, performing resisted medial rotation involves many other muscles, but only in a minor way. A good resisted test focuses the major portion of the stress on the structure being tested.

If the test result is negative and the practitioner still suspects that this structure is injured, an adjustment in the test can be made to stress the structure more intensely. By including the additional step of stretching the structure before applying resistance, most or all of the fibers are forced to come into play during the test.

For instance, if resisted medial rotation is negative with the elbow at the person's side and the forearm held out in front of the body, the humerus should be laterally rotated such that the hand and forearm open laterally. This stretches the subscapularis, increasing stress on the muscle during the test. This added testing element often clarifies which structure is injured.