Veronica is working her rear delts and upper back. This simple exercise is anything but simple when she does it. All the muscles you read about in Grays are visible in this clip, that is, her astonishing trapezius, the amazing prominent ledges of her posterior deltoids, and just below them the teres and teres major. When she moves the weight in and out, there is the superior serratus posterior standing out strong, and the twin triangles of the rhomboids bulge up prominently. Further down, you see her thick erector spinae and there are the thin slabs of the thoracolumbar fascia. Holding her arm... Show more