Asking For The Rein-Back
To perform the rein-back, the rider applies both leg aids and a resisting hand. The leg asks the horse to move, but the hand prevents the horse from going forward, so it instead releases that energy in a step back. As soon as the horse begins to step back, the aids are released. The rein-back should be performed in a straight line, with the rider's legs used softly behind the girth to keep the hindquarters straight.
The upper body of the rider stays upright, leaning neither forward nor back. Leaning back is especially bad, as it drives the seat bones of the rider into the horse, causing the animal to hollow its back.
It is sometimes useful to transfer the weight of the seat onto the thighs when asking for the rein back, so that the horse may easily round up through its back and engage its hind end.
When the rider wishes the horse to stop moving back, the rider sits deeper into his seat, adds more leg, and lightens his contact with the horse's mouth.
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