I recently got a standing desk, and it also happens that my company's HR department has a program where they issue pedometers and we log our daily steps and if we hit a certain threshold (360,000 steps in 10 weeks) we can take a half day off. Well, I figured out that I can walk in place at my standing desk and get 15,000 steps a day and relax when I get home. Who needs a treadmill? Walking in place is just as good and doesn't force your upper body to move as much.