La martingale is the bridle or bridle that attach the strap to the noseband and it serves to prevent the cavalry from raising their heads more than necessary. In this way the rider does not lose contact with the mouthpiece.
It also serves to the reins always arrive from the same direction, no matter how much the rider raises his hands. It is used a lot in the jumping discipline. It can be used in combination with the strap or individually. The action it exercises is not modified.
Types for each horse or discipline
Fixed Martingale. This can be more restrictive and should not be too short. The strap is attached to the girth and between the front legs of the horse and through the neck strap, secured by a rubber stopper, linking at the noseband.
Sliding Martingale. It consists of a strap that slides along a loop in the neck strap from the cinch, and is divided into two branches that have a ring at their ends. These have to reach the withers or the throat of the horse. The reins go through these rings on both sides of the neck. To prevent a ring from catching the buckle in the bit and being dangerous, it is important that there are stops on the reins.
Irish Martingale. They are especially suitable for racehorses. It is very simple, it has two rings separated by a short piece of leather that holds the reins in place on both sides of the horse's neck.
Martingale Bib. Especially recommended for foals. On several occasions they are used in thoroughbred horses and breeds with large heads or neck flexion. It has two rings joined by a piece of leather, which prevents the ends of the rings from getting caught in the mouth or the teeth of the horse.