Like so many people I adopted an off-track retired Standardbred (*pacer) horse and trained her, a mare, to do a near perfect saddle rack. Few realize that the smooth racking gait can be developed in just about every Standardbred once they are comfortable under saddle and able to keep moving in a straight line on quite lose reins. With consistent training the horse will learn to transition from the ordinary walk, to the running walk, right up into a very smooth single-foot rack. If pushed for additional speed the rack might change into a rougher side to side pace. The difference is easily noticed. This is where you raise the reins slightly, ask the horse to slow down and head down to fall back into the running walk or saddle rack.
Learn more about gait training for your Standardbred horse here.