Anatomy and Physiology - Skeletal Muscle Fibers

Types of Body Movement

ORIGIN

The point of attachemt to the immovable or less movable bone

INSERTION

Point of attachement to the moveable bone

PRIME MOVERS

The muscle that has the majority of the responsibility for causing a particular motion.

ANTAGONIST

Muscles that oppose or reverse movement

SYNERGISTS

Help prime movers by producing the same movement or by reducing undesirable movement by stabilizing them

FIXATORS

Specialized synergists. They hold a bone still or stabilize the Origin of a prime mover so the tention can be used to move the Insertion bone.

5 GOLDEN RULES

1. With a few exceptions, all skeletal muscles cross at least one joint.

2. Typically, the bulk of a skeletal muscle lies proximal to the joint crossed.

3. All skeletal muscles have at least 2 attachments, the Origin and the Insertion.

4. Skeletal muscles can only pull; they never push

5. During contraction, a skeletal muscle insertion moves toward the Origin.

 

Dorsiflexion and Plantar Flexion

a. Flexion b. Extension c. Hyperextension

Abduction, Adduction, Circumduction

Inversion, Eversion

Opposition

Supination, Pronation