Chapter 6 The Muscular System 83 Copyright Goodheart-Willcox Co., Inc. May not be reproduced or posted to a publicly accessible website. Name ________________________________________________________________ Date ________________________ Class ________________ Activity 6.2 LABORATORY INVESTIGATION Agonist vs. Antagonist Muscles Objectives At the completion of this activity, you will be able to: • Explain the difference between agonist and antagonist muscles. • Identify agonist and antagonist muscles in major body movements. Materials personal protective equipment light dumbbells or free weights (optional) Pre-Lab Review 1. Review the major muscle groups outlined in your textbook. 2. Define the following terms: A. agonist _ _______________________________________________________________________________________________________________________ _______________________________________________________________________________________________________________________ ______________________________________________________________________________________________________________________ B. antagonist _ _______________________________________________________________________________________________________________________ _______________________________________________________________________________________________________________________ ______________________________________________________________________________________________________________________ Procedure Working with a partner, perform the following basic movements, as shown in the illustrations. While completing each action, feel for which muscle is producing a concentric contraction. Which muscle serves as the antagonist for each movement? 1. biceps curl (elbow flexion): light dumbbell or small classroom object (Figure 6.2A) A. concentric muscle contraction _ ___________________________________________________________________ __________________________________________________________________ B. antagonist muscle _ ___________________________________________________________________ __________________________________________________________________ Figure 6.2A Saskia D. Richter, author