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.