are specially trained in advanced dressage horses: the Piaffe and the Passage. The Piaffe is essentially created by asking the horse to trot in place, with very little forward motion. The Passage (rhymes with "massage") is an exaggerated slow motion trot. Both require tremendous collection, careful training and considerable physical conditioning for a horse to perform. Riding technique Depending on the horse and its speed, a trot can be difficult for a rider to sit because the body of the horse actually drops slightly between beats and bounces up again when the next set of legs strike the ground. Each time another diagonal pair of legs hits the ground, the rider can be jolted upwards out of the saddle and meet the horse with some force on the way back down. Therefore, at most speeds above a jog, especially in English riding disciplines, most riders post to the trot, rising up and down in rhythm with the horse to avoid being jolted. Posting is easy on the horse's back, and once mastered is also easy on the rider. To not be jostled out of the saddle and to not harm the horse by bouncing on its back, riders must learn specific skills in order to sit the trot. Most riders learn to sit a slow jog trot without bouncing. A skilled rider can ride a powerfully extended trot without bouncing, but to do so requires well-conditioned back and abdominal muscles, and to do so for long periods is tiring for even experienced riders. A fast, uncollected, racing trot, such as that of the harness racing horse, is virtually impossible to sit. Because the trot is such a safe and efficient gait for a horse, learning to ride the trot correctly is an important component in almost all equestrian disciplines, particularly for equitation riders. "Gaited" or "ambling" horses, which have smooth 4-beat intermediate gaits that replace or supplement the trot, are popular with riders who prefer for various reasons not to have to ride at a trot. There are three ways the trot may be ridden: Sitting: The rider's seat remains in the saddle the whole time while following the motion of the horse and without bouncing. This is required for show ring western riding and preferred in dressage, especially at the upper levels. Sitting the trot gives the rider optimum control, because he or she can use the seat and