ISSA Unit 4

Flexion

A decrease in the angle between two body segments.

Isometric Contraction

A muscle activation in which the muscle fires but there is no movement at the joint and no change in length of the muscle.

Eccentric Contraction

A type of muscle activation that increases tension on a muscle as it lengthens.

Concentric Contraction

A type of muscle activation that increases tension on a muscle as it shortens.

Pronation

Assuming a facedown position. Of the hand, turning the palm backward or downward. of the foot, lowering the inner side of the foot so as to flatten the arch. The opposite of supination.

Prime Mover (agonist)

Denoting a muscle in a state of contraction, with reference to its opposing muscle, or antagonist.

Abduction

Movement of a body part away from the midline.

Adduction

Movement of a body part toward the midline.

Circumduction

Movement of a part, e.g., an extremity, in a circular direction.

Frontal (coronal) plane

Separates the body into anterior and posterior parts.

Antagonist

Something opposing or resisting the action of another.

Neutralizer

When a muscle contracts to counteract an undesirable action of another muscle.

True Synergy

When a muscle contracts to stop the secondary action of another muscle.

Co-Contraction

When both the agonist and antagonist undergo contraction.

Helping Synergy

When two muscles contract together to create one movement.

Midline

An imaginary longitudinal line that travels down the center of the body,

Extension

An increase in the angle between two body segments, or the return from flexion.

Supination

Assuming a horizontal position facing upward. In the case of the hang, is also means turning the palm to face forward. The opposite of pronation.

Rotation

Circular movement of a body segment about a long axis.

Hyperextension

Extension of a limb or part beyond the normal limit.

Plantarflexion

Extension of the ankle, pointing of the foot and toes.

Assistant Mover

Muscle that plays a secondary role to the prime mover involved.

Stabilizer

Muscle that steadies or holds a body part in place.

Sagittal (anteroposterior) Plane

Separates the body into right and left sections.

Transverse (horizontal) Plane

Separates the body into superior and inferior sections.

Stabilization

The act of being stable or balanced.

Kinesiology

The science or study of movement, and the active and passive structures involved.

Biomechanics

The study of the mechanical aspects of physical movement, such as torque, drag, and posture, that is used to enhance athletic technique.

Inversion

Turning inward, as of the sole of the foot.

Eversion

Turning outward, as of the sole of the foot.

Dorsiflexion

Turning upward of the foot or toes or of the hand or fingers.