story identification - What book - boy travels from home city and gets distended by gravity?

I read a very special book a few years back. We follow a boy who lives in a world where, if one moves far enough in a direction, that person gets distended and changed in size.

The boy works on laying tracks for the train, on which his city is. The city has to continually keep moving or it also will get squashed.

It's like a world like if one end is pinched and then dragged out like a piece of rubber string or bubble gum.

The book is not older than 10 years I think.

Hope I was clear enough...

Answer

That sounds like Inverted World by Christopher Priest, although it's forty years old.

To quote from the linked Wikipedia article:

Helward lives in a city called "Earth", which is slowly being winched along at an average speed of 0.1 miles per day (0.16 km per day) on four railroad tracks northward toward an ever-moving, mysterious "optimum".

Upon reaching adulthood at the age of "650 miles", Helward leaves the crèche in which he has been raised and becomes an apprentice Future Surveyor. His guild surveys the land ahead, choosing the best route.

When Helward is assigned to escort three women back south to their village, he is astonished by what he learns about the alien nature of the world. As they go further south, the women's bodies become shorter and wider, and they begin to speak faster and in a higher pitch.