There could be several reasons why your horse stops and pops up. Here are some possibilities:
• The saddle may not fit properly; it could pinches at some point, and so the horse stops and pops up.
• The bit may not fit right.
• The shoes (if wearing any) may cause this behavior.
• It may even be a joint problem.
• It could be a behavioral issue that the horse has learned. The horse may have learned that by stopping and popping up in the air, he gets to stop doing what he has been asked to do or even gets unsaddled. This is a learned behavior, and the horse is taking advantage of you.
Seek a professional horse person who may be able to assist you in changing your horse's current behavior through training techniques as well as fitting your bit and bridle properly. You can also have a professional saddle fitter help determine if the saddle fits correctly.
If it is a learned behavior, you will need to ride the horse past this point, and teach him that just because he pops in the air, he still has to continue on and perform what you ask. This will take time. You will need to continue this same process again and again. The horse will have to learn that popping up in the air is unacceptable behavior. To reward the horse for acceptable behavior, stop the him and ask him to stand, but never do this after he has popped up in the air. If he pops up in the air, make him move again and perform some exercise.
