Muscular System

1. Muscular System Learning Goals: Know major muscles and their functions Match exercises to muscles used understand movement terminology

2. Major Muscles of the Body • Good interactive site: http://www.exrx.net/ Refer to handout/anatomical diagram and chart for muscles you should know.

3. Movement Terms • Flexion – bending the joint to reduce the angle • Extension – straightening the joint (increasing the joint angle) • Abduction – movement away from the midline • Adduction – movement toward the midline • Supination – lateral rotation of forearm • Pronation – medial rotation of forearm • Plantarflexion – increasing angle b/n foot & leg • Dorsiflexion – decreasing angle b/n foot & leg • Elevation – raising up to a more superior position • Depression – pulling down/lowering to an inferior pos.

4. What Muscle Does It Work? • Complete chart…consider weight training and/or body weight exercises.

5. Use of Muscles • Agonist: the muscle that is primarily responsible for the movement (e.g. pec. Major in a push up) • Antagonist: the muscle opposing the prime mover (e.g. lat. Dorsi acts as an antagonist to pecs in push ups) • Synergist: assists the prime mover; helps stabilize the joint

6. Muscle Actions • Three main types: • Concentric contraction: shortening of muscle fibre • Eccentric contraction: lengthening of muscle fibre • Isometric contraction: contraction of muscle fibres occurs but there is no joint movement (e.g. wall sit or flexed arm hang)