[pmontra]

The runner will feel a pull to the left, as if the track had a slope in that direction. I wonder if that could give motion sickness to somebody. Probably people sent to the Moon will be selected against that because of the journey to and from the Moon but I really have no idea about that.

Another problem, as pointed out by someone else in the comments, is that the floor is not flat but points upward and the feet and ankles might feel that. Furthermore it's another possible source of motion sickess (flat but not flat.)