Join Date: Oct 2007
Location: Alberta, Canada
• Horses: 0
First off, is she sore anywhere? Whenever someone tells me that their horse is swapping leads in back and bucking, I automatically think that the horse is exhibiting signs of pain. It's hard work to cross-fire like that, much harder than just cantering on the correct lead all around. First thing that comes to mind is out in the lumbar spine, out in the pelvis, or even looking at OCD (HalfPass just went through this same thing.)
It may be a training issue, but it might be something physical; I would strongly suggest you get a vet out to make sure she isn't sore, and triple check your saddle fit. Once you've cleared those two potential problems/causes, then I'm more than happy to give training advice.
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