I would do a lot of work with draw reins it helped my young appendix a lot on the flat
My friends horse used to do this as well. You should keep your inside leg on and support her with your outside rain. Make sure your not falling in as well because it will be even harder for her to correct herself.
My mare used to do this. More outside rein will help her stay balanced through the circle. My coach always says straightness and balance first... then bend
Lateral work. Turn on the forehand. My horse does this to the left. I always am focused on testing where he is on his responsiveness to my left leg by warming up with turns on the forehand, leg yield, I basically ride him in shoulder-fore all the time to the left, and use of proper shoulder-in as well as haunches in. Lateral work, lateral work, lateral work!
Use your inside leg to hold her shoulder up
I had this same problem with a pony I used to ride! What really helped me was constantly changing lead and doing lots of circles. My pony struggled more in canter so I always made sure we warmed up for quite long before we cantered that really helped. Lateral work is also great! Maybe get your trainer to make sure you keep your leg on and don't drop your rein:) good luck!
My OTTB did the same thing so what I did was a very small circle to the left and put my left leg on so his left hind with cross over his right but then catching it and putting your right leg on and having the right shoulder cross over the left. and opposite direction to keep them balanced. It makes you need to have control over the whole body. Another thing is you need to keep your right hand higher and because my boy would bulge so much my leg wasn't strong enough and he was still learning how to move off the leg I would carry a dressage whip and when he bulges put my leg on, keeping my hand high, and press the whip to his shoulder. Not hit just press to signal the shoulder to move over. Eventually he learned and he doesn't bulge but it just takes persistence and patience. Hope that helped :)
My OTTB did the same thing so we workeds on lots of shoulder out hanch in and shoulder in hunch out
Definitely not lame, I think maybe because she raced left it's different for her to bend right
I think your horse might be a bit lame. If she bobs her head in the circle then she is definitely lame or has something wrong with her foot/leg
Thanks guys, saddle has been fitted to her and her transitions are great. I tried serpentinesans and squared and found it helped!!
Try lunging her on the pisoah training system . It teaches them how to balance and carry themselves correctly
Transitions, Transitions and more transitions
Spirals on a circle going inside and back out. Do them slowly at a walk, trot and eventually a canter.
Focus on using your legs to balance the horse and keep them from falling to the inside, step on the outside stirrup, just step do not lean. Hold your reins together and level, not dropping one or the other. Mind your upper body to keep it straight and not dropping your hips/shoulders to the inside of the spiral.
softening drills, stretching warm ups and cool downs are probably something that could help. Even though it appears you are more into English riding, there are a lot of western riding techniques that could probably help your horse. Good luck!
Stretching them out after a work out might help it does wonders for my thoroughbred gelding along with riding exercises.
It might be some kind of stiffness and lack of balance on that specific rein - Ride a square and lateral work to engage her shoulders and make her pick it up.
Just to be sure, I would check saddle fit. It could be that she's avoiding discomfort from a right bend.
Serpentine loops and 10m and 20m circles
Put 4 poles on the ground in a + formation. Slow trot a circle, trying to stay in the middle of each pole and ask the horse to pick up their shoulder. This is what one person suggested I did with my lease horse and it worked great. It helped reinforce that she had to listen to me when I asked her to pick up her shoulder so when we started cantering again she followed my cues to lift her shoulder. I hope this makes sense and/or helps! :)