You want ideas from the master? Let me ask Sunrise and get back to you..
Actually it's a very very simple thing to teach. It just requires patience and a lot of carrots.
You horse WILL feel your movement on his back. You can't hide it from them! However you move.
If you're consistent with the way that you present your own flexion, he will learn to be too.
I recommend to get yourself really nicely centred and balanced first though, and sit tall as though a string is suspending you from the top of your head. Turn with your own chin level. It feels then to me that my inside is opening up a space for the horse to bend into and my outside supports that bend. My outside calf muscle will be brushing softly on the horses side, and my inner hanging away slightly. This could be different depending on your own idea of what appropriate cues are though.
I start by tuning up with lots of well known and liked tasks and treats first so my horse knows we're playing and is aware that I'm asking something. Then I sit central and quiet, until she relaxes and stands straight. Sometimes I reward a few times for this as an intermediate step if the horse is a bit hyper,
making sure I pass the treat directly under her chin. not around to the side. (I think this is a very important part of why Sunrise's flexions are good. When I'm riding her, I NEVER feed her with her head around to the side, unless it's for a task that included flexion. I always bend myself right down and feed her in ramener. This way I avoid reinforcing her for "twisted" flexions where she's tipping her nose up to me for the treat, which can happen if I'm in a hurry trying to get the treat to her. With horse straight and relaxed, I simply turn and wait!
She'll probably feel that something has changed and start to fidget around and experiment with what she can do to gain a reward. When she accidentally does the right thing, I C/R.! That simple!
Some horses may need a little more help to get the right answer. I often incorporate my "here's a task" verbal, which for us is a kissing sound. That tells the horse to start offering behaviours. If he's really not getting it and is losing interest, I may help him more by extending my hand as with an opening rein and clicking my fingers for attention, or even asking for "here" as in a finger target. If I do this though, it's really important for me to stay balanced so that my original "body" cue stays the same. If I lower my hand as in luring, it puts me off balance and I lose the cue I want to teach. I could swing the back of my hand round to touch my horse behind the saddle flap. This also draws their attention to the correct side, and is a nice way of reinforcing the riders correct body position. You see a lot of reinless demonstrations where the riders use this technique.
The trick, as with all CT, to getting fast results is to C/R for even the slightest move in the correct direction. If I can see one eye, I C/R. Then I lean down and feed the treat on that side. Soon, the horse will bend right around on anticipation of the treat. I get my hand as low as possible when I feed, to avoid the horse having to tip his nose up. If he's tipping up, I'll pass my hand further towards the front, back towards ramener position before releasing the treat.
I teach one side solidly, then the other, then start mixing them up.
Some difficulties.
-The horse bends the wrong way. I've found that once they've flexed the wrong way, they throw me completely off balance, and my position is all wrong for the bend I'm asking. It will feel to them as is they're right, because I'll be forced into following their bend. So I've learnt not to insist. Instead, I just relax completely, even hang my head down, and wait till they give up and stand straight, before asking again.
- The horse starts to pre-guess me. Same answer.
- The horse begins to walk. Stop her, go back to the spot, relax, and ask again.
Later, when they are really strong at the halt, and know that I don't want them to walk off, I start to add some energy to my outside leg, and this exercise turns into a walk piroette with lovely bend. Then, with the addition of teaching them to respond to a quarters over cue, I've found that I can turn it into a halfpass movement.
Volker, if you're already sitting on Mucki sometimes, you could start this exercise now because you don't have to ride him. Just sit there and feed him treats!
When you do start riding him, it'll be so easy!
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I have not sought the horse of bits, bridles, saddles and shackles,
But the horse of the wind, the horse of freedom, the horse of the dream. [Robert Vavra]