Ok, today I tried to circle Zeph today, and he's the friendliest horse I've ever seen, and he LOVES to be around people... but we can never get him to trot while on a line unless you run beside him. So I took a Carrot Stick and really beat the ground just to get him to walk out (in the saddle you don't need much to make him go but on the ground its really hard). When I finally hit the ground so hard, he reared and trotted out bucking, he stopped, to I hit the ground once again (to make he keep going not out of anger), he cantered out bucking wildley. I tried to turn him and go out the oposite direct, he reared once again, and continuosly bucked. I allowed his wiggles to get out, then he came back into meand I pet him before we cleaned up his hooves, and we put him back. Undersaddle, he rears up a little before going but he throws his head too. I doubt he was properly trained or never lunge trained. He is 8 years old 15.3 hands, gets 2 cups of Triple Crown Complete with supliments + fesque hay. We work with him daily (playing the 7 games and going on trail walks). How can we fix the rearing and bucking and head tossing?