Got a staircase? Or maybe 14? I happen to work in an 8 story building, of which has a quiet, heated eight-floor staircase. Recently I took up running up the staircase instead of taking the elevator. Please make sure you're prepared for the extra stress on your knees, because I felt it almost immediatly after getting back into ergonomic office stance. So, do some hills, some stairs, and maybe don't wear pretty shoes to work.