The year is 6741.

Everyone is running, but there was no apocalypse nor disaster; nothing was happening. It seems like the human body has evolved to the point where if they stop moving, they die. Everyone here always kept eating {due to excessive movement} and keeps running, whoever stopped either dropped dead or gained a few too much pounds. Because if you stop, you either die instantly or gain weight.

You see no cars, because those are sitting down and driving; every massive futuristic building here are made of high steps of stairs, every elevator is large enough for people to walk around it, every hoverboard requires for you to keep walking, running or pull-ups for it to run.