Can you improve arm strength?

Just remembering back when we traded for Steve Walsh….the knock on him, and oh man was it true, was that his arm strength was pretty average/poor and I remember hoping that he could just find a way to become stronger and we’d have one really good QB. I think he ended up skipping those arm strengthening days at Saints camp. ;)
I don't know if this is true or not but I seem to remember someone saying that Danny Wuerrfel's football IQ was as high as Peyton Manning's, it was his arm strength that would keep him from being a good QB