Speed Up Your Slow Horse
One of the hardest things, is that as you ride your horse, the more you mess with the bit, the more you restrict movement. You're restricting movement every time you pick up the rein. If I have a horse that doesn't want to move and I pick up that bit, restricting his movement, then it's going to take more drive from me to keep this horse wanting to move. It actually makes it harder for me to keep the horse moving through it, but he's actually learning it better.
Here's what to do when your horse "won't go."
You can fix the lazy horse as you ride through any exercise. The first thing that makes a horse responsive or lighter is having a clear cue from you, the rider. A cue is something that you ask the horse and can get the horse to do. That means a cue to stop will be picking up the reins. That would be a cue to stop. A pre-cue is something you do before the cue. A pre-cue is "ho." If I ride forward and I say "ho," and he doesn't stop, I'm going to say "ho" and pick up the reins to say "That meant stop." So pretty soon, when I ride forward and I say "ho" the horse stops. So a pre-cue is something you do before a cue that makes a horse lighter and more responsive. It's the same thing with your legs. What do you do before you use your legs? You sit forward, pick up the reins, kiss to them. But what's the first that you do before you squeeze or kick your horse? You take your legs out. You take your legs out, then you bring them together. So practice that. Practice taking your legs off and if he doesn't move, then tell the horse "Hey, that meant move" with a kick. And when you bring them together, be prepared to kick until something happens. So practice that and pretty soon, when you take your legs away from the horse's side, that'll mean "move forward." So I'm not using my legs to keep kicking my horse. Practice this and remember, when you bring them together, bring them together hard enough to get a change of leg speed. If you kick him and you just kick him to keep him going, then it's only going to get worse.