This image shows our gelding Regal schooling undersaddle. In this photograph I am riding Regal in an indoor arena with dressage tack and a blue saddle pad. This horse is schooling training level dressage, working at a trot with his head on the bit and his back arched. Schooling the trot in a correct frame, with his back arched, not only looks nice but also helps keep horses sound longer in life. Think of a suspension bridge, suspension bridges are always built arching up, bridges are never build arched downward. This is because the upward arch is a stronger structure than a downward arch. A horse that is ridden with an inverted hollow back, especially by larger riders, more frequently develop back problems later in life and can even develop swayback conditions when the ligaments supporting the back breakdown. By riding a horse in this type of frame, with their back arched up and stepping correctly under themselves, a horse can comfortably carry more weight, longer, easier, with less or no long term damage to their backs. It's a misconception that heavier riders are more difficult to carry for a horse, a rider who knows how to get a horse to carry them correctly and balanced will always be easier to carry than a smaller inexperienced rider.