Chocobo sprint ability? or... Chocobo Racing?
http://imageshack.us/a/img717/474/jp201302152.jpg
It is entirely possible that this is a race between the two people on chocoback and the effect happening in front of the rider on the left is a checkpoint.
Maybe it sits there stationary and players must run through it?
(Think old school arcade racing games)
But what can explain the running cactuar?
Maybe he is racing too?
Just a thought. It might not be the sprint ability.
Edit:
Found the video that shows the current sprint animation:
http://youtu.be/-3joG4TVBKU?t=2m54s
It looks nothing like the above image.
If indeed this is the chocobo sprint ability, why use a new animation?
Food for thought.