It thinks

Scene: RJ is throwing Bauer's ball across the dining room and I am on the treadmill. Also located in the dining room.

Me: Did you see that?

RJ: See what?

Me: Did you see the speed of the treadmill spike?

Right after I said this the treadmill picks up speed again for 2-3 seconds and then settles back to it's programmed speed.

Me: See? There is something wrong with it. It looks like it's between 2.3 and 3 mph that it randomly speeds up.

RJ: Maybe it thinks you should work a little harder.

Me: You can leave now!