Okay so let me first say that I am TERRIBLE at drawing back muscles, dear god. I had to do some studying myself before making these illustrations. Anyway, I must remind you that I am NOT the anatomy master here. This is just what I do to draw back muscles, looking up and using photo reference yourself is the best way to learn anatomy. I’m just translating the human body to my own art style. Once you learn anatomy, you can translate the human body to your own style.
Anyway, here:
and see, check it out. The shoulders are being pushed back, like I said when I showed you how to do arms.
It’s important to note how the shoulder-blades overlap the muscles, and vice versa, depending on if the arms are raised or not.
Oh, and here’s a pattern that’ll hopefully simplify the muscle layout a bit. Memorize that pattern, and back muscles’ll be easier.
Anyway, here’s a quick little thing, I hope I helped at least a little bit.it sure helped force me to learn back muscles a bit better.