Muscle · Shoulders

Middle trapezius

Pars transversa musculi trapezii

The middle trapezius is the horizontal band of the trapezius, running from the spinous processes at the base of the neck straight out to the shoulder blade. Its job is simple and important: it draws the shoulder blade back toward the spine and holds it there while the arm works. When it is not doing that, the shoulder blade drifts forward and the arm loses the stable base it needs to move from — which is why scapular retraction appears in almost every posture and shoulder programme. In Momentum's system it belongs to the scapular stabilisers, a group that chart lists as inhibited rather than tight: a muscle to switch on and load, not one to chase with pressure.