Muscle Storm | Back Muscles Close Up ❄️🔥 . . Superficial Layer 1. Trapezius: This large muscle extends from the back of the skull to the middle of the back and helps in moving the shoulders and supporting the arms. Latissimus Dorsi: Located on the lower back, it aids in shoulder movement and helps with pulling actions. 2. Intermediate Layer Rhomboid Major and Minor: These muscles are located between the shoulder blades and help retract the scapula. Serratus Posterior Superior and Inferior: Thes