Transitions are the ultimate exercise for training the horse to better balance and collection. By nature, the horse is balanced toward the forehand, so if you sit on your horse and let him move on long reins, 60 percent of his total weight is on the forehand. That’s his natural balance, and there is nothing wrong with that. However, if you go forward to trot or canter, the horse goes more on the forehand, and we want to avoid that.
Transitions, half halts and other dressage exercises train the horse to change his balance in motion, bit by bit, from being 60 percent on the forehand to a 50/50 balance, and finally to a balance where more weight is carried on his hindquarters than on his forehand. This is the principle of improving balance and developing collection–the purpose of dressage.
In the transition from canter to trot, the principle of preparation, waiting and final execution of the transition is exactly the same as in the trot-walk transition. The initial shortening of the canter stride–best done on a circle in training–prepares the horse for the transition to trot. Then you do not allow your horse to do the transition. You ask him to stay honest in the hand, and he must wait for your final aid so you can make those in-between steps into a gymnastic exercise that will improve his collected canter.
I make these transitions smooth by thinking about the speed of each gait. If your normal canter is seven miles per hour, and your normal trot is five miles per hour, then you want to slow down the canter speed to five miles per hour, which is a form of collection, before asking for the trot. Then the transition will be smooth because the horse is going exactly the same speed as the new gait.
If the horse breaks to trot too early, it means that he is not accepting the aids for slowing down the canter. Perhaps the shorter strides are too hard for him. If so, the waiting moment in the transition shouldn’t last too long. Be pleased with steps that are only slightly shorter and then accept a trot that is a little bit bigger than you want. In this case, you don’t do what is ideal. You do what is possible for your horse. If on the other hand you think he is able to slow down the canter, then you need to get after your horse a little bit and insist on your collected canter.