What a great topic. Just a bit of background of me. I ride racehorses, so I sure know the meaning of getting run off with very well. Its happened to me several times. Its part of the job!

The best thing you can do when a horse takes off is sit back, keep your hands low, sea saw the reins, and keep doing it until the horse stops.

The purpose of sitting back is to let the horse know that you want to stop, not go forward. It also allows you to use your body strength and not just your arm strength to aid in stopping the horse.

The purpose of keeping your hands low, is to encourage the horse to keep him head down. If you move your hands up high, he is able to get his head up and you have no contact with the bit.

The purpose of sea sawing the reins is to keep the horse from locking up on the bit and giving you no control.

You should be able to stop a runaway horse within a few stride if you do it right. If not, then your screwed until the horse wants to stop!