haha my Flash does the same thing to the pasture but the lady before trained him to slow and he gets worked up outside the arena, as she never road him outside. Adn I walked him down the road with just a halter and lead and it seemed to help I will jump on and make him walk every once and a while he eats. And he seemed much better, I do loung work with him twice a day when its not REALLY hot out like its been and I ride once a day. And really get after him when he tries to get away with things. Make things hard where he wants to be and easy where you want him.
I did this in the pasture when he wanted to go to the others in the pasture next door. I trottted and did circles near them and walked and did troting in larger circles away from them and he would walk away from them in the end if I asked and after some walking I got off and put him with them.