The document summarizes various muscles of the trunk, including: - Intercostal and diaphragm muscles that are important for respiration and breathing. - Three layered muscles of the abdominal wall that form a strong protective covering over the abdominal cavity. - Back muscles that allow movement and stabilize the trunk, including erector spinae and interspinalis groups. - Pelvic floor muscles like levator ani and coccygeus that form a hammock-like floor across the pelvis. - Shoulder muscles that attach the upper extremity and allow movement, including pectoralis major, deltoid, serratus anterior, trapezius and levator scapulae