It wasn't clear to me that running into a sign knocks you down, since it just cuts immediately to you being knocked down, and recovering from being knocked down was annoying since you immediately start running at full speed once you get up.
The gameplay itself is fun, and I think being able to speed up at your own will was nice. You could probably make it more interesting by varying the level layout and adding more obstacles, like maybe one that would require you to slow down to time its cycle properly.
Lastly, I think the dust particles lack polish, since they aren't pixelated.