Yep, I assume that you are referring to the stuff that used a spiral steel strip that was about 1/2' wide and about a flexible as a tree branch, correct? Today's stuff is a walk in the park compared to that.
Not to mention, they were probably using hand drills (brace and bit) when they were wiring houses with that cable. No wonder everyone walked around looking like Popeye the Sailor in the late 30's! After hand-drilling a house and dragging that cable around all day, I imagine that there was no need for additional exercise.