Why is she doing this?

[Keket]

Coquette has learned passage. No, we don't know how, because most days, getting her on the bit in trot can be a challenge.

But every now and then, only during rising trot, she'll -really- tuck underneath herself and lift her feet off the ground with this moment of suspension at the top. It only lasts a few strides, but why is she doing this? To my knowledge, I'm not doing anything differently when she does this, and if I was, my RI would spot it.

[Skyhuntress]

Some horses that passage under saddle without being asked to do so because they are feeling really pressured and/or nervous.

The other thing that sometimes happens is that the rider really has a death grip on the horse's mouth, and without much leg, the extra energy has no where to go.

But just out of curiosity, are you sure she's not trying to extend a bit and you keep on checking her with your reins?

[Keket]

Some horses that passage under saddle without being asked to do so because they are feeling really pressured and/or nervous.

The other thing that sometimes happens is that the rider really has a death grip on the horse's mouth, and without much leg, the extra energy has no where to go.

But just out of curiosity, are you sure she's not trying to extend a bit and you keep on checking her with your reins?

Hm, no, not nervous. She's a very laid back horse and I'm a fairly laid back rider. And when she does get nervous it's very obvious as her head shoots up and her eyes get big and she's all over the place. And I wouldn't think it's my reins because I ride her on little to no contact (she's a Western horse first and an English horse second and isn't fond of contact).

[puzzles]

perhaops as she begins passage she becomes too collected, or changes her position because she finds it dificult to carry you and perform this excersise in the way you want her to, therefore she may be addapting in order to perform the movement.
make sure she maintains impulsion, without too much 'whoa', and especially if she is fairly young/progressing fast, spend time on the lunge and completing plenty of regular hillwork to build up her strength and posture.
will your RI also have a look at her? often the opinion of another expert will help too.
good luck
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