I’ve mentioned the term ‘open hips’ previously as well as why hip mobility etc is all important, and a lot of folk may think this only applies if you’re a dressage rider. Not at all, it applies just as much to showjumpers/ cross country riders as well.
A jumping position is a fluid seat, one that changes as the horse's balance changes. It keeps the rider in a position over the horse's center of gravity, and for that reason your influence on the horse is far greater some may say then those on the flat. That ability to open your hips (the angle from your torso to the thighs) and constantly be able to adjust the angle between your thigh and torso is vital.
You can then give the horse the freedom he needs to jump an obstacle, lifting both the front and hind legs tight thus less chance of a rail down/ fall.
You can encourage the horses to bascule over the jump, this better technique means over time he can then jump higher.
As a rider you are providing the horse with the support needed to not interfere over the jump but maintain secure position on take off and landing to allow safe recovery, getaway and effectiveness in setting up for the next obstacle.
You place less stress through the horses front limbs on landing as your balance is in line with his. Reduction of injuries.
The riders jumping position:
The rider should not bring their hips too far forward, over the pommel, getting in front of the movement. If that happens, your weight changes and places you in a potentially dangerous position. This change in balance, then also increases stresses placed through the horses front limbs.
Your hip joints and pelvis are especially important, they are the connection from your upper body that must be adjustable, to the lower leg that is to be still and stable. The hips must therefore be flexible and allow for opening and closing of the angles. The riders balance must also allow for the hips to be moved backwards, not forward as we outlined in the previous point above.
During the landing phase, your horse moves away from your body because you're adjusting your balance, and allows your hip angle to open and you become more perpendicular to the ground. It is important that you, the rider, simply allow this movement to happen.
They should ride with a more open chest with shoulders back (not an overly rounded back), this position will stop the rider from collapsing forwards, thus center the weight from the upper body over the lower leg and contribute to a more secure position.
We must also consider a riders lower back area, and a rider who is strong enough to support in balance a two point position between fences or across country.
The effect of a riders head position must be taken into account, looking down causes the shoulders to lean and round forward. This can be placing them into becoming forward precarious position with the pelvis coming up away from the saddle into a forked position.
A rider who tilts their head to one side, will again change the lateral balance and place more weight onto that side, subtle it may be, but it still affects the horse
So as you can for riders who jump it's crucial to be aware of your position and its influence on the horse.