If you're enough floors up: descending in an elevator then immediately ascending by the stairs works wonders for the sedentary body, and the mind. I also do this sometimes when hacking through lunch to trick my mind's context, then reverse the journey to start the afternoon.
I assume the benefit is partly the fact you're taking a break for an extended period of time away from the computer, so why wouldn't you just walk down the stairs and get the elevator up?
