horse bolting problem

Question
hello sir, may i know why do horses bolt?? how to stop a horse from bolting??

Answer
Horses are prey animals. That is, they are eaten by predators. From the beginning, horses have had the "fight or flight" instinct to keep them from being eaten by other predators. At the first moment of a perceived danger, their instinct tells them to RUN. Run NOW and stop to look at what they were running from later when they are a safe distance away. If they feel trapped, then the "fight" instinct takes over. But the very first thought in their mind is to run away from danger. That is why a horse bolts. To run away from a perceived danger real or unreal.
The best way to stop bolting is to condition your horse through training to listen to you and obey your cues. If this is not possible, then a one-rein-stop is required. This takes a little  practice. You must be quick and smooth to do it. If you hesitate you will find your horse out of control and you on the ground.
With one hand, you smoothly pull ONE rein around to flex the horse's head to the side. This takes the horse off-balance and takes his leverage away. Once his head is flexed to the side, the horse will probably go in circles. Keep the head flexed to the side and the horse will do smaller and smaller circles until he comes to a stop. This is like an emergency brake on the horse. But as I stated before, the best way is to condition your horse through proper training to listen to you and to trust you.