What kind of back curvature is indicated by 'swayback'?

Swayback, which is also referred to as hyperlordosis, is characterized by an excessive inward curve of the lumbar spine, typically in the lower back region. This condition can lead to a protruding abdomen and a change in posture where the pelvis tilts forward. The lumbar curvature specifically refers to the curvature of the lower back, making it directly related to the phenomenon known as swayback.

In contrast, thoracic curvature pertains to the upper back, cervical curvature relates to the neck, and pelvic tilt involves the position of the pelvis rather than the curvature of the spine itself. Therefore, understanding the specific region of the spine affected by swayback confirms that the correct answer revolves around lumbar curvature.