Movement

Movement (or motion) is the act of moving — a change of place or posture, or transference by any means from one situation to another. Humans move from place to place through coordinated movements and postures.

Human movement

The movement produced by the human body through the contraction of muscles and the bending of bone joints is called human movement. Human movement is controlled by the nervous system, and it therefore involves the coordinated use of muscles, ligaments, joints and bones working together.

How the body actually produces a movement

A movement does not happen because a single muscle acts alone. At almost every joint, one muscle (the agonist, or prime mover) contracts and shortens to create the movement, while an opposing muscle (the antagonist) relaxes and lengthens to allow it — for example, the biceps contracts as the agonist while the triceps relaxes as the antagonist during elbow flexion. This coordinated give-and-take, directed by the nervous system, is what makes a movement smooth rather than jerky.

Voluntary and involuntary movement

Not every human movement is consciously controlled. Voluntary movements — walking up to bowl, raising a racket to serve — are initiated and directed by conscious thought through the brain. Involuntary (reflex) movements — blinking when something approaches the eye, the knee-jerk reflex, the heartbeat — happen automatically, often through the spinal cord, without conscious effort. A sports skill usually begins as a slow, consciously-corrected, voluntary movement during early practice and becomes faster and more automatic with repeated training — which is exactly why repetition and drilling matter in coaching.

Movement versus locomotion

Movement is one of the things that distinguishes a living thing from a non-living thing. It is the change in the position of an object: in the body it happens when a living organism moves a body part, or a combination of parts, to bring about a change in position. When this change moves the whole organism from one place to another, we use the special term locomotion. So:

• Movement — a change in the position of a body part.
• Locomotion — a change in the position of the whole organism.

Why this matters to a physical educator …