The back muscles are arranged in several layers so they are divided into the superficial and deep which in turn are arranged in two layers. Here are only back muscles which define a relief in your back workout for mass.
Trapezius – flat, wide muscle, takes the position of the surface at the back of the neck and upper back. It important muscle in your best back workout for mass. Trapezius muscle is triangular in shape, the base facing the vertebral column, and the top – to the scapula acromion; trapezius muscles of both sides together have the shape of a trapezoid. The tendon muscle bundles are short and only in the lower cervical and upper thoracic vertebrae, reaching great lengths to form diamond shaped tendon pad. Bunches of muscle converge radially toward the blade.
Primary function: cutting all bundles, muscle brings the shoulder blade to the vertebral column; cutting the upper beams, raises blade and lower – lowers it. When fixing the vanes both trapezius muscles pull the head back, and with a unilateral reduction of muscle tilts the head in the proper direction.
Latissimus dorsi – occupies the entire lower part of the back, approaching its upper part at the lower end of the trapezius muscle. It originates from the spinous processes of the last four (or sometimes five and six), thoracic and all lumbar and sacral vertebrae, as well as on the back of the iliac crest, and finally, four teeth on the lower four ribs. These teeth are alternated with the back teeth of the external oblique abdominal muscles.
From the beginning of their places of the latissimus dorsi muscle fibers go upwards and laterally in a convergent direction and attached to the crest of a small tubercle of the humerus (crista tuberculi minoris humeri). Be careful during all the back workout routine for mass.
Primary function: shoulder leads to the body and upper limb pulls back to the midline, turning it inward (pronation). With reinforced upper extremity closer to her body or is involved in the displacement of the lower ribs up with the breathing motion, thus being the auxiliary respiratory muscles.
Rhomboid muscles lies beneath the trapezoid shape having a rhombic plate. It starts from the spinous processes of the two lower cervical and upper four thoracic vertebrae and is attached to the medial edge of the scapula.
The main function in mass building back workout: while reducing the rhomboid muscles pulls the shoulder blade toward the spine and up. Fixes the medial border of the scapula to the chest.