What ground exercises develop a horse's responsiveness to leg and seat aids before riding?

Several ground exercises directly simulate and prepare the horse for the leg and seat aids he will encounter under saddle, creating a physical and mental vocabulary that makes the transition to ridden work significantly smoother. The goal of these exercises is to teach the horse to move specific parts of his body away from specific pressure cues, so that when a rider applies similar pressure from the saddle, the horse already has a clear understanding of what is being asked. Yielding the hindquarters is perhaps the most important preparatory exercise. The handler stands near the horse's shoulder and applies rhythmic pressure with a hand or rope end on the horse's flank, asking him to cross his hind legs and step away laterally. This directly mirrors the action of a rider's inside leg driving the haunches away in a sidepass or leg yield. A horse that yields his hindquarters freely and softly on the ground will be far more responsive to the leg-yield aid under saddle than one that has never experienced this type of directional cue. Yielding the forehand — asking the horse to cross his front legs and step his shoulders away while the hindquarters remain relatively stationary — simulates the opening rein and indirect rein aids that ask a horse to move his front end in ridden work. This exercise is also the foundation of the spin in Western reining and the pirouette in dressage. Long lining introduces the horse to bilateral rein contact applied from behind — very similar to the contact a rider establishes through a rein and bit — and teaches the horse to steer, halt, and bend in response to rein pressure before anyone sits on his back. Horses that have been long lined have generally already learned to soften to bit pressure, respond to direct and indirect rein cues, and balance themselves through turns, which translates immediately to better responsiveness in the first ridden sessions. In combination, these exercises mean the horse arrives at his first ride already knowing much of what the rider will ask — making that first experience calmer, safer, and more productive for both horse and rider.