In Plain English
The abs are the muscles running vertically down the front of your abdomen, extending from the ribcage to the pelvis. They flex your spine, help stabilize your torso during movement, and create the segmented “six-pack” appearance when sufficiently developed and lean.
Technical Definition
The abs refer primarily to the rectus abdominis, a paired muscle originating from the pubic crest and pubic symphysis before inserting onto the xiphoid process and the costal cartilages of ribs 5–7. Tendinous intersections divide the muscle into its characteristic segments. Its primary functions are spinal flexion, posterior pelvic tilt, and resisting spinal extension through isometric contraction while working alongside the rest of the abdominal wall to stabilize the trunk.















