California Riding Magazine • May, 2008

Go Bitless!
The BitlessBridle -
Dr. Robert Cook’s quiet revolution

by Rebecca Sparenberg

Since the Bronze Age, the purpose of the bit has remained relatively the same - a piece of metal in the mouth, thought to control a horse’s pace, flexion and direction. According to veterinarian Robert Cook, what has changed is the number of bits being used at any one time and their severity, which has greatly increased. He says technology has made it possible, with leverage, to apply fiercer force not only to the bars of the mouth but also, by means of a thumbscrew (curb and chain), to the whole of the lower jaw and the roof of the mouth. This can also be used in accordance with painful pressure applied across the bridge of the nose and even to the poll. In the last 10 years, Robert has been trying to reverse this trend with his “quiet revolution” - the BitlessBridle.

Unlike hackamores and other traditional bitless bridles, all of which Robert says are pain-based, the BitlessBridle works on an entirely different, two-loop concept. Based on a figure-of-eight, crossunder design, it is a pain-free rein-aid. “The horse’s mouth is one of the most sensitive parts of its anatomy,” explains Robert. “Bits hurt horses and frighten them. Fear is expressed by one or more of the five Fs - fright, flight, fight, freeze and facial neuralgia (head shaking).”

Robert was introduced to the crossunder concept by Allan Buck of Ramona in 1997. Since then, he has traced the history of its development to Ink Grimsley, a bulldogger from Spink, CO affectionately known as, Ink of Spink, in the 1950s. A bulldogger is someone who owns a string of horses which they rent out to rodeo riders for cutting practice. Ink was worried about the mouths of the horses he rented out being cut and bruised by rough cowpokes. He developed an earlier version of the BitlessBridle—which ensured the safety of his horses’ mouths by eliminating the bit.

Since then, Robert has further developed this painless and safer rein-aid, and introduced it to the public. Drawing on 50 years of research into diseases of the horse’s head, he explains why the bit is a bad idea. “I kick myself for not having recognized this years ago,” says Robert. “Most english style riders all assumed a bit was necessary. I certainly did until I tried the crossunder bridle. The dramatic improvement in a horse’s behavior obliged me to ask myself the question, ‘What does a bit really do to a horse?’”

How Does the BitlessBridle Work?

It follows the principle that where the head goes, the horse follows. Brief pressure on one rein pushes painlessly, but persuasively on the opposite half of the head, allowing the rider to steer. Robert says horses respond better to being nudged painlessly with the BitlessBridle than being pulled painfully by a bit, and improved steering is one of the first of many benefits that riders notice.

To stop or slow a horse, brief pressure on both reins or alternate pressure on each rein hugs the whole of the head, creating a sensation that is interpreted by the horse as a polite request to stop. According to his website,, there are two major reasons why the “brakes” on the BitlessBridle are more reliable than those provided by a bit. First, bits or traditional bitless bridles cause pain and this triggers flight. Secondly, a horse can disarm a bit by grabbing it between the cheek teeth or trapping it under the tongue. Doing either blocks the bit’s signals.

Since graduating from the Royal Veterinary College of London in 1952, Robert has spent most of his career as a clinician, teacher and researcher in clinical departments at schools of veterinary medicine in the United Kingdom and United States. Currently, he is Professor of Surgery Emeritus at Tufts University in Massachusetts. He believes that the work he has done to investigate the bit method of communication in the horse and to validate the BitlessBridle is doing more to help horses and riders than anything he has done previously. In his book, Metal in the Mouth: The Abusive Effects of Bitted Bridles, he talks about the 100 negative behavior reactions the bit causes, some of them highly dangerous, like bolting, bucking and rearing. “Bit pain makes a horse ‘deaf’ to signals, uncooperative and unhappy. Painless signaling fosters a true partnership and facilitates the harmony that is every rider’s goal.”

In the past Robert says that there weren’t really any good alternatives to the bit available. “All the traditional bitless bridles have their limitations. Some are better for stopping than steering, while others are better for steering than stopping. Now we have an efficient, safer and humane option. There are no welfare, safety or performance contra-indications for use of the BitlessBridle. The only limitations are those currently mandated by the FEI and national federations. Rule change proposals from riders and drivers are urgently needed.”

For more information, to order the BitlessBridle or to read free articles by Dr. Robert Cook visit or call toll free, 866-235-0938.