Jumping position

The jumping position is a position used by equestrians when jumping over an obstacle. It usually involves what is known as the "forward seat" or "2 point" because the rider's legs provide two points over which the rider's weight is balanced on the horse. It was first developed by Captain Federico Caprilli. This involves the rider centered over his or her feet, with the stirrup leathers perpendicular to the ground. Continuing a line upwards from the stirrup leathers, the head and shoulders fall in front of the line, as do the knees, the hips fall behind it.

A correct jumping seat serves two purposes:

The jumping seat is not meant to be held by the rider, but rather it is a fluid seat that changes as the horse's balance changes. It keeps the rider in a position over the horse's center of gravity.

It is important to note that the horse, not the rider, is responsible for opening and closing the rider's angles (notably, the hip and knee). As the horse takes off, it raises its upper body off the ground and comes closer to the rider. This makes the rider's hip angle (between the thigh and chest) close. Over the fence, the rider keeps the angles closed. As the horse lands, it moves away from the rider's body, which allows the hip angle to open and the rider to become more perpendicular to the ground. Also, if the horse takes a jump wrong in some manner, due to rider error or other, the rider may be thrown around a little bit and may sometimes get 'left behind', where the rider's center of balance is behind that of the horse's. This can also throw the horse off balance and lead to other problems such as knocking down a rail.

The lower leg is the anchor of the rider's position, and contributes a great deal to his security. Poor lower leg position makes a rider more likely to lose balance over fences, and therefore increases the chance that he may fall. It also tends to decrease the ability of the rider to communicate clearly with his or her horse.

The leg should hang down the horse's side, making even contact along its whole length (inner thigh, knee, and calf), and should not change position when the upper body moves. The rider's weight is dropped along the back of the leg and into the heel through a flexible ankle, so that the heel is lower than the toes. The toes are generally turned out slightly, to a degree greater than in the flatwork-only English riding disciplines such as dressage or saddle seat. This places the back of the calf against the horse, instead of the whole inner calf as in dressage, which decreases the refinement in communication between horse and rider, but anchors the rider and increases security. Toes should turn no more than 45 degrees out.

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Wikipedia