When cantering I start twisting in the saddle what can I do about that?

Twisting in the saddle at the canter — rotating the upper body so that one shoulder moves forward and the other moves back, or the hips rotate so that one moves forward and the other drops behind — is one of the most common canter position problems and one that is particularly difficult to self-correct because the twist often feels like straightness to the rider experiencing it. The most common cause of twisting at the canter is an asymmetrical following response to the canter's movement. The canter produces a rocking forward-and-back swing through the horse's back that the rider's hips must follow asymmetrically — the inside hip drops and swings slightly forward and the outside hip follows slightly behind on each stride. A rider whose hips are not equally mobile on both sides will follow this movement more freely with one hip than the other, and that unequal following produces the rotation that presents as twisting. The hip that is tighter falls behind as the canter swings forward, the shoulder on the same side drops back to compensate, and the twist is established. The inside hip dropping excessively is the most common specific pattern. At the canter on the left rein, if the left hip drops too much or swings too far forward, the left shoulder compensates by coming forward and the right shoulder drops back, producing a twist to the left that is particularly visible from directly behind the horse. The correction begins with identifying which direction the twist goes and which hip or shoulder is the primary mover. Video from behind and from the front provides this information clearly. Once the specific pattern is clear, the correction is to consciously stabilize the primary mover — the hip or shoulder that is moving excessively — rather than trying to move the trailing one, because stabilizing the excessive movement on one side naturally allows the trailing side to catch up. Longe line work at the canter without stirrups is the most effective tool for addressing canter twisting because it removes the rider's ability to use the stirrups to compensate for the asymmetry. Placing both hands on the hips during longe line work allows the rider to feel directly whether the hips are moving symmetrically or whether one is moving more than the other with each canter stride — a tactile awareness that is difficult to develop any other way. Off-horse exercises that develop equal hip mobility address the physical root of the asymmetry that the canter reveals.