I have both a standing desk and a desk treadmill. Personally I think you have to be a bit of a masochist to use a standing desk alone for more than 15 minutes per hour. I have used anti fatigue mats, massage balls under my feet and objects to alternate resting legs on and it never clicked until I bought the treadmill.<p>My ideal is walking 1-2 mph while working. Doesn't distract me from work and by the end of the day I find I've walked 5+ miles mindlessly.