What is the name of a fast horse trot?

Answer 1

If you are riding a "fast horse trot" it could be a lengthened or an extended trot.

That is referring to the actual length of stride a horse is making at that trot.

"Collection" is the exact opposite, basically, of a fast trot.

Answer 2

Well, your QUESTION is asking for the fastest HORSE,which was Secratariet. Although, the fastest SPEED of a horse is a gallop