The easiest fix would be to put all posts that contain "muscle" without "muscle memory" (since numerous questions use that phrase legitimately) through the Low Quality Posts review queue.
I realize that's not optimal, since LQP isn't really designed for flagging/identifying spam. An alternative would be to insert it as a task for First Posts at the top for quickest handling, since the vast majority of spam, in my experience, is its user's first and only post.
Maybe it would be nice if there was a Triage queue here like there is on Stack Overflow? If there is a secret internal examination place, problematic terms like "muscle" could be a good keyword to send stuff into there.