Anatomy & Physiology muscle movements

The Origin

the proximal/medial attachment point of a muscle that remains stationary during contraction.

The insertion

the distal/lateral attachment point of a muscle that moves during contraction.

a Flexor

a muscle that decreases the angle between two body parts, typically bending a joint.

an Extensor

a muscle that increases the angle between two body parts, typically straightening a joint.

an Abductor

a muscle that moves a limb away from the midline of the body. (T posing)

an Adductor

a muscle that moves a limb toward the midline of the body. (pencil pose)

Rotation

the movement of a body part around its axis, such as turning the head or twisting the trunk.

Internal Rotation

the rotation of a limb or body part toward the midline of the body, commonly seen in shoulder and hip movements.

External Rotation

the rotation of a limb or body part away from the midline of the body, often involved in shoulder and hip movements.

Circumduction

a circular movement of a limb that involves a combination of flexion, extension, abduction, and adduction, commonly seen in shoulder and hip joints. (complete 360 movement)

Inversion

the movement of a joint toward the midline of the body, often seen in ankle and shoulder movements.

Eversion

the movement of a joint away from the midline of the body, primarily observed in the ankle and shoulder.

plantarflexion

the movement of the foot downward at the ankle joint, such as when standing on tiptoes or pointing the toes.

Dorsiflexion

the movement of the foot upward at the ankle joint, as seen when lifting the toes off the ground.

Pronation

the rotation of the forearm or foot, turning the palm down or the sole inward.

Supination

the rotation of the forearm or foot, turning the palm up or the sole outward.

Endomysium

the delicate connective tissue sheath that surrounds individual muscle fibers/cells, providing support and helping to maintain the structure of the muscle.

Perimysium

the coarser fibrous membrane that surrounds bundles of muscle fascicles, providing support and structure to the muscle.

Epimysium

the outermost tough connective tissue layer surrounding an entire muscle, providing protection and support. when it gets really think it is called a tendon and connects muscles to bones.

Muscle fiber (cell)

a cylindrical cell that makes up skeletal muscle, responsible for contraction and force generation.

Fascicle

a bundle of muscle fibers surrounded by perimysium, contributing to the overall structure and function of skeletal muscle.

muscle

a tissue composed of fibers that can contract to produce movement.

Bone

a rigid organ that forms the skeleton, providing structure, support, and protection for the body's organs.

ligament

a fibrous connective tissue that connects bones to other bones at joints, providing stability and support.

tendon

a flexible band of fibrous connective tissue that attaches muscles to bones, enabling movement.

Fixator

a muscle that stabilizes a joint or body part during movement, allowing other muscles to perform their actions effectively, does not move.

Prime mover

the main muscle responsible for a specific movement, also known as an agonist.

Synergist

a muscle that assists a prime mover in performing a movement, helping to enhance its effectiveness.

agonist

another term for prime mover, the muscle that initiates a specific movement.

antagonist

a muscle that opposes the action of a prime mover, helping to control movement and maintain balance.