What action best describes spine extension?

Spine extension refers to the movement that occurs when the back straightens or arches backward, effectively lengthening the spine. This action involves the engagement of muscles along the posterior chain, such as the erector spinae, and helps to open up the chest and improve posture. In contrast to flexion, which involves bending forward and decreasing the spinal angle, spine extension increases that angle by lifting the torso backward. This movement is essential for maintaining proper alignment and can also help alleviate tension in the lower back when performed correctly. Understanding spine extension is crucial for designing effective fitness programs and ensuring the safety of participants during workouts.