...
παίρνω φόρα = to run up, to gain momentum
You're right, Theseus, καλύβι is a hut, but Καλύβια is a town and area in Mesogaia, East Attica.
However, it may very well be used here as the common word "καλύβια" to serve the rhyme with "φρύδια" (probably implying not the eyebrows but another...