There is a lot of discussion around seat and leg position in riding horses – the role of each, what one is trying to achieve etc. To strip away all of the detail what we are trying to do is sit on our horses back as lightly and relaxed as possible, to go with their movement whilst remaining in balance and not pulling them of one way or the other. If I were to sit on your shoulders and lean one way or another I would pull you around and possibly make you loose balance. This is what we are doing on a horse.
The aim therefore is to sit as lightly as possible using our legs, and stirrups to help us to stay on top of the horse, while using our core as our main stabiliser. Our own balance and stability keeps us there – we should not be gripping with our thighs and knees and hanging on to the reigns.
When we hang on to the reigns we are literally jabbing the horse in the mouth with the bit, which is at worst “cruel” and at best “not very comfortable”. This causes the horse to lift his head in the air sink his back and prevents him using his core and driving from the back end. I would hasten to go so far and pointing out that this can be a major contributor to soreness in horses backs.
Our trunk should be able to support itself. If we hold a weighted bar vertically it does not take much effort to keep it there – if we lean it even every so slightly we will have to grip onto it harder to hold it from falling down. This is the same as us leaning our body forwards from our hip joint (leg to pelvis) we will feel a substantial increase in core load as we do this – providing we remain straight and do not fold in the middle – as in the jump position in riding and to a certain extent going around a corner.
The second pointer is not to be gripping with our knees and thighs to hold on. If we look at various teachings we need to be at one with the horse, without being heavy. We need to be sitting around him and going with him without inhibiting his movement and “blocking” him. If we push into the stirrups we will lift our bum off the saddle and have a tense leg. Tension in our legs is hard and not comfortable for the horse, and one of the signals to slow a horse down is to “hold” or “block” them. To slow out movement and they will follow. With time the horse will become responsive to simply the movement of the pelvis as a sign to speed up and slow down.
We cannot be light on our seat if we are not balanced and clinging on. A good visualisation is that of our legs being like a clothes peg down each side of the horse and our body straight up. The area of strength is at the top of the arch, where the string goes through – our bum. So we stabilise from our bum. As the horse turns or we wobble we should be using out bum – our gluteus muscles to hold our torso above out centre, rather than centrifuging off to the outside of the bend. I think a good thought is to be pushing from the feet into the head – so lengthening the body and becoming lighter all the way through – not pushing up from the feet and lifting the seat off the saddle, but sitting taller and lighter. As if standing.
The key is in strengthening this core control so that we can hold our balance and be independently balanced on our horse. Only then can we use our hands and arms and our legs freely to guide and aid the horse with symmetrical actions.