To understand the damage caused by draw reins you need a clear picture of the hollowing reflex. The hollowing reflex is the nervous reaction that makes horses hollow. It causes muscle tension along most of their top line from ears to tail. It is a reflex reaction triggered by almost any perception of pain or discomfort. It starts at the poll where it is difficult to observe. It ends in the tail.
Passive, draw reins hold the bit against the tongue at the bars level or above. Active, they press the bit against the tongue. In the worst cases they press the bit against the bars. They always cause pain or discomfort that triggers the hollowing reflex. Used lightly they tend to immobilize the tongue. Subsequently, all the muscles around the back of the skull become tense and the horse hollows.
The immobilization of the tongue is not readily visible. It happens because the bit presses against the thick of tongue. To relate to the feeling remember times when someone checked your throat with a tongue depressor. To feel what happens use the handle of a spoon to press behind the middle of your tongue and immobilize it. Hold it down for a short time eventually your salivation stops.
The tension in all the muscles around the back of the skull may be visible at the poll. As soon as the tension at the poll happens, you can observe the hollowing tension propagating along the top line. It is highly visible at the base of the neck and along the back. Once the hollowing reflex has been triggered, it is too late to stop it. Most often it becomes a reflex triggered by the lightest contact of the bit.
Often riders use draw reins to stop head tosssing. Horses tend to become hollow and end up tossing their head as a reaction to the perception of some pain or discomfort. Draw reins will force horses to flex at the poll in spite of the muscle tension. Doing so they also trigger the hollowing reflex. The hollowing reflex becomes a habit. Therefore they tend to perpetuate the habit they try to eliminate.
It is preferable to solve horse training and riding difficulties with correct therapeutic procedures and gymnastic exercises. Select only bits and reining devices that do not immobilize the tongue and do not trigger the hollowing reflex. For example, Baucher Snaffles, roller bits, and reining devices deflecting the bit toward the corners of the lips are much better options than draw reins or martingales. |