The chains themselves do not hurt the horse. Their purpose is to get the horse to step UP and OUT. They feel them and then will lift their legs in an attempt to step out of them. Some react as expected(see above) and others don't. If I put them on my trail ASB, he wouldn't think a thing about them. Granted, he is not gifted with any sort of high motion which is why he is a trail horse. With my breed, if they don't have it, you can't make them have it. Luckily, we are pretty good at breeding for it. Now, put a pair of light chains on my show colt who was born with great motion and the right attitude, and he reacts accordingly, stepping up an out. Since we don't and can't use these in the shows, it shows that they are simply practice devices, used to encourage a certain way of moving. It is for the sensation of something there that encourages lift.
To prove a point, one of my friends took her horse out, and tied a strand of fishing line loose like a bracelet around the pastern. He moved like you had put chains on him. It was just to prove that it was not pain which causes lift in conjunction with something around the ankles, it is merely the sensation of something there that the horse feels the need to step out of.
Horses do get used to them, and if over used, will have zero effect on a horses motion. Posted via Mobile Device