Muscle Movement

Origin – where muscle is attached to immovable or less movable bone Insertion – where muscle is attached to the bone that is being moved

Types of movement 1. Flexion – decreases angle of a joint (brings bones closer together) 2. Extension – increases angle of a joint (increases distance between bones)

Abduction – moving a limb away from the midline of the body Adduction – moving a limb towards the midline of the body

5. Rotation – movement of a bone around an axis

6. Circumduction – combination of flexion, extension, adduction and abduction seen in ball-and socket joints

Muscle Interactions 1. Prime mover – muscle mainly responsible for a movement 2. Antagonists – oppose or reverse a movement (do the opposite of the prime mover)

3. Synergists – help prime movers by either producing the same movement or reducing undesirable movements

4. Fixators – specialized synergists that stabilize the origin of the prime mover