Seriously folks. People in the horse world need to stop being so god damn stupid and selfish, and to think of their horse for once. I'm sick of people jumping young horses, just because they want to jump, and they have no patience, so they just get on with it and jump their young horses. JUST RIDE ANOTHER GOD DAMN HORSE. For Christ's sake. Honestly people. Just because you see another idiot jumping their 3 year old, doesn't mean it's right, or that you should do it too. Horses aren't physically or mentally ready to jump until they are AT LEAST 5 years old. Some lighter horses, even older. Stop being selfish and training your horse to jump early just because you want to jump now. Go take lessons at a local barn who has horses that you can jump, or borrow a friend's horse. What's the problem with waiting two years until your horse is of age to jump? They're still going to jump the same when they are 5 instead of 3, so I don't see what the problem in waiting is. The only thing your doing by jumping your horse at 3 or 4 is pretty much guaranteeing early lameness and leg problems, along with setting the horse up to burn out at an early age and get sour to jumping. Seriously people, just wait. For your horse's sake.