Chapter 6 The Muscular System 87 Copyright Goodheart-Willcox Co., Inc. May not be reproduced or posted to a publicly accessible website. Name ________________________________________________________________ Date ________________________ Class ________________ Activity 6.3 LABORATORY INVESTIGATION Manual Muscle Testing Objectives At the completion of this activity, you will be able to: • Explain the importance of manual muscle testing. • Describe concentric, eccentric, and isometric contractions. • Perform four basic manual muscle tests. Materials personal protective equipment straight-backed chair or table Background Manual muscle tests (MMTs) utilize isometric contractions to test the strength of specific muscles. It is important to remember that the purpose of MMTs is not to cause fatigue or pain, but to elicit a contraction and check the ability of a muscle to contract. When completing MMTs, the clinician is producing a force to elicit a contraction, but there should be no active movement of the joint being tested. Pre-Lab Review 1. Review the major muscle groups outlined in your textbook. 2. Compare and contrast the three forms of muscle contraction: concentric, eccentric, and isometric. What do they have in common? What is different? _ __________________________________________________________________________________________________________________ __________________________________________________________________________________________________________________ __________________________________________________________________________________________________________________ __________________________________________________________________________________________________________________ __________________________________________________________________________________________________________________ _________________________________________________________________________________________________________________ Procedure Work with a partner to perform each of the manual muscle tests in this activity. Before beginning, decide which partner will first play the clinician and which will be the patient. (When all the tests are complete, you will switch roles.) Note: All steps are directed to the clinician. CLINICIAN TIP You should always verbally explain what you are about to do before completing any procedure on a patient. Practice that now with your partner by saying something such as, “I’m going to press on your leg.” Leave a slight pause after your statement in case the patient has objections to the procedure.