Muscle Groups

Skeletal

Muscle that is attached to bone. Striated, contractions are voluntary.

Cardiac

Branching chains of cells; uninucleate, striations. Involunory contractions.

Smooth

Visceral. Single, fusiform, uninucleate; no striations. Involuntary contractions.

Origin

Muscle is attached to the immovable or less movable bone.

Insertion

Muscle is attached to the movable bone, and when the muscle contracts the insertion moves towards the origin.

Prime mover

Muscle that has the major responsibility for causing a particular movement

Antagonist

Muscles that oppose or reverse a movement

Flexion

Angle of two parts of a limb is decreased

Extension

Increasing the angle between two portions of a limb or parts of the body

Abduction

Movement of a limb away from the median line of the body.

Adduction

When a limb is moved from an outward position towards the median line.

Rotation

Partial revolving of a body part on that part long axis

Circumduction

Rotational movement of a limb in a ball and socket joint

Supination

Movement of the palm of the hand and the forearm upward by rotation

Pronation

The palm of the hand is moved from an upward facing position to a dowanrd facing position.

Isotonic

Muscle shortens and movement occurs

Isometric

Tension in the muscle increases, but the muscle does not contract

Atrophy

Decrease in the mass of the muscle

Hypertrophy

An increase in size of skeletal muscle through an increase in the size of its component cells.

Paralysis

Loss of muscle function for one or more muscles.

Spasm

Sudden, involuntary contraction of a muscle, a group of muscles

Naming

Direction of the muscle fibers, Relative size of the muscle, location of the muscle, number of origins, location of the muscle's origin and insertion, shape of the muscle, and action of the muscle all