Building a treadmill desk

[scaeagles]

I might suggest going with a clear desktop - acrylic or some thick plastic or something - so that you can see the controls. Then reaching under shouldn't be as much of a problem as you can see the controls without bending over.

How thick is the bottom of the cupholders? I'm sure your desk will be a bit heavier than the typical water bottle so you may need to reinforce them in some fashion.