https://www.nma.art/videolessons/drawing-the-male-back-in-sanguine/

In this video lesson, world-famous artist and instructor Glenn Vilppu shows you how to create a forceful yet sensitive drawing of a muscular male back using only the sanguine conté pencil. You will learn how to use anatomy, construction, and rendering to develop the forms of the figure and carry a movement throughout the drawing. You will also learn the entire sequential process of making the drawing from initial block-in to the final rendering.