Which action is referred to as spine extension?

Spine extension refers to the action of increasing the angle between the vertebrae of the spinal column, which typically occurs when a person bends backward from the waist. This movement is important for maintaining proper posture, improving flexibility, and engaging the muscles of the back. When bending backward, the spine moves into an extended position, which helps to counteract the effects of activities that involve leaning forward or sitting for prolonged periods.

In contrast, bending forward from the waist involves spinal flexion, which decreases the angle between the vertebrae and brings the torso closer to the legs. Rotating the spine involves twisting motions, which do not fall under the definition of extension. Bending beyond normal limits typically refers to hyperextension or excessive extension, which can lead to injury if not performed correctly. Therefore, the action of bending backward from the waist directly represents spine extension as it aligns with the anatomical definition of the movement.