It also depends on what you mean by distorted? In FCP are you editing 4X3 or 16x9?
If you mean that it is either squished or stretched, double click on the clip in the timeline to open it in the viewer, go into the motion tab click on the distort disclosure triangle and check your aspect ratio. [lust move the slider back and forth to see if it makes the image look more like you expect].
If it does, it probably will no longer fit in the canvas correctly which means the sequence settings between FCP and Motion are different.