No matter what your horses breed or conformation keeping your horse uphill in dressage is paramount. The faster you go the more your horses inclination is to take more weight on the front end. Think of when you were a kid and would see a big hill and want to roll down it. Once you start to roll down the hill gravity ensures that you will get a rush as you go faster and faster!
From all my experience training and riding horses a big factor in having success, especially at the canter is understanding how to get the horse to balance more weight on the hind legs. One way to help your canter be more uphill, is to imagine that you are cantering your horse up a hill in the field. Here I am working on an uphill canter with one of my young horses.
