Rectus abdominis. A deep groove was cut under the white tights. The name is rectus abdominis. The rectus abdominis is located in the sheath of rectus abdominis on both sides of the midline of the anterior abdominal wall. It is a narrow muscle band with wide upper part and narrow lower part, which starts from pubic symphysis and pubic tubercle, and the muscle fibers stop in front of sternal xiphoid process and 5-7 costal cartilage.