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The effect of bit-induced pain in the horse on the feelings of riders about riding (2022)

Original article


Robert Cook[1] and Matthew Kibler[2]

(Address for correspondence:



Background: This is the second part of a questionnaire-based study. The first part (Cook and Kibler 2018) showed that removing the bit from 66 bitted horses reduced 69 behavioral indices of pain from a population total of 1575 indices when bitted to 208 when bit-free; a reduction of 87%.

An additional ten questions were answered by 45 of the 66 riders who reported how their personal feelings about riding changed when they rode bit-free. The rider data now complement the horse data.

Objectives: The hypothesis tested was that riders would have fewer negative perceptions about riding when their bit-free horse was not experiencing bit-induced pain.

Study design: A retrospective questionnaire study, of a self-selected population of recreational riders, to document the negative affective experiences of both horse and rider when riding with and without a bit.

Methods: See Cook and Kibler (2018)


  • When using a bit, 45 riders reported having a total of 200 negative feelings about riding.
  • When bit-free, they reported 18, a reduction of 91%.
  • Rider’s feelings were negatively influenced by their horse’s aversion to a bit

Main limitations: 

  1. The inherent limitations of all questionnaire studies.
  2. The 45-horse population in this study is a subset of the 66-horse population in the companion study, so the totals for each population are not matching sets though each, independently, is the first data set of its kind.


Removal of the bit significantly reduced the prevalence of bit-induced aberrant behaviour in the horse and the level of concern in the rider, thereby increasing safety, improving performance and allowing riders to achieve that sense of harmony with their horse that is the goal of horsemanship.  Based on welfare and safety grounds for both horse and rider, it is recommended that rules requiring mandatory-use of the bit for equestrian sport be repealed to allow riders the choice of competing bit-free.


Key words: horse, bit, behavior, welfare, safety



It has been shown that horses can sense a rider’s fear. But to what extent do riders sense a horse’s fear? Behavioral data have shown how 66 horses responded to rider’s signals when ridden with and without a bit (Cook and Kibler, 2018). Apart from a previous study of four horses (Cook and Mills 2008), this remains the only other batch of such data to be compiled. To date, no data have been published on how the rider feels about riding with and without a bit, i.e., on what the horse is signaling to the rider. The objective of the present article is to analyze this additional evidence from the parent study. An open letter to the British Horse Society commented on the need for change (Glendell 2014). It included the observation that “The presumption that horses should be bitted and shod with metal shoes persists, without any scientific justification.” Use of the bit has been questioned for ~20 years (Cook 1999, 2011, 2014, 2016a, b, 2019a, b, 2020, 2021, Cook and Strasser 2003). Independent evaluations of the aversive welfare impact of bit use have reached similar conclusions (Glendell 2014, Mellor and Beausoleil 2017; Mellor 2020, Tuomola et al 2019). In the meantime, additional designs of pain-free bitless equipment have been explored and recommended (Hanson and Cook 2015, Hanson 2019). Robinson and Bye (2021) concluded that forces exerted by the noseband of a bitless bridle on a horse’s nasal plane could be detrimental but did not measure and compare these with the forces of a bit in a horse’s mouth. A compilation of the evidence to date comparing bitted and bit-free horsemanship has been published (Cook 2021). The prediction is that when bit-free competition is allowed, this will reveal the cause of a number of common equine diseases that are currently classified as ‘unknown’, i.e., idiopathic.


A questionnaire-based study of the behaviour of 66-horses (Cook and Kibler 2018) included a second part consisting of ten questions that explored the personal feelings of the riders about riding when their horse was bitted and again when bit-free (Table 1). Of the 66 riders who answered the earlier questions about their horse’s behaviour, 45 answered questions about their own feelings. Completed questionnaires were returned over a period of 10 years between 2002 and 2012. The methodology and demographics of the population were described in Cook and Kibler (2018). All respondents to the 10 questions about rider feelings were female.

Statistics for the difference of proportions was carried out on each of the ten questions about riders’ negative feelings while riding with and without a bit. The null hypothesis was that there would be no difference in the number of negative feelings when a horse was bit-free compared to the number when bitted. The alternative hypothesis was that there would be a difference.


Collectively, to all ten questions, riders reported a significant reduction in the number of negative feelings about riding when their horse was bit-free (Table 1 and Figure 1).  The null hypothesis was refuted.





Number of “YES” answers when BITTED

Number of

“YES” answers when


Z Statistic for two proportion significance test



A loss of that sense of harmony between horse and rider that is so critical to all good horsemanship



z = 7.07

p < 0.0001


Development of a sense of frustration with apparent inability to master the art of equitation



z = 6.27

p < 0.0001


Riding ceases to give the rider (or the horse) pleasure



z = 5.55

p < 0.0001


Self-evaluation of riding skills as ‘poor’ when, in fact, horsemen should be blaming their ‘tools’ (i.e., the bit or bits)



z = 5.81

p < 0.0001


A burgeoning annoyance bordering on anger with the horse



z = 4.56

p < 0.0001


An increasing reluctance to exercise the horse on a regular basis and the generation of displacement activities (excuses)



z = 4.06

p < 0.0001


Loss of confidence, fear of riding, and a decision to give up riding altogether



z = 3.50

p = 0.001


Decision to sell or breed from a horse that appears to have incurable problems and to buy another for riding



z = 2.90

p = 0.004


Economic embarrassment from doomed attempts to treat problems by means other than by removal of their cause, the only logical treatment



z = 2.68

p = 0.007


Personal injury (anything from fractured collar bones to near death experiences)



z = 1.97

p = 0.049


Table 1: Showing the Z statistic and p-value for each of the ten questions on how riders’ feelings changed following removal of the bit. All values were significant at the alpha level of α = 0.05



To recap, based on 69 questions about horses’ behaviour, 66 riders in a variety of disciplines documented their horses’ negative experiences when ridden with and without a bit (Cook and Kibler 2018). What were consequently recognized as sixty-nine bit-induced pain indices were reduced from a combined total of 1575 when bitted to 208 when bit-free; a reduction of 87%.

Now, based on 10 questions (Table 1) about 45 riders’ negative perceptions about riding, there was a decrease in the combined total of 200 such perceptions when bitted to 18 when bit-free, a reduction of 91%. 

The study suggests that the effects of the bit on the horse may be one reason why some riders quit riding. Anecdotally, the experiences that motivate horseback-riding as a sport are variously described in terms of euphoria, exhilaration, excitement, wonder and amazement. All of these may be true for some riders, some of the time. But there is another side to the story that includes dismay, frustration, disappointment, inadequacy, fear, annoyance, anger, injury, expense, resignation and a decision to give-up riding altogether. Collectively, the three most common feelings of riders when riding bitted were a lack of harmony with their horse, a sense of inadequacy as a rider, and failure to derive pleasure from riding (Table 1).  

A rider’s negative feelings about riding could serve as an early warning of the increased likelihood of an accident occurring in subsequent rides (Cook, 2016a). If riders were to develop the habit of keeping a post-ride logbook of problems encountered during a ride, this could prompt them to seek the cause and find a solution before an accident occurs. A horse in pain can be expected to be more prone to accidents. As the evidence indicates that the bit is a major cause of pain in the ridden horse (Mellor and Beausoleil 2017; Cook and Kibler 2018; Mellor 2020, Cook 2021), removal of the bit represents a logical step towards prevention of pain and reduction of risk. Hospital admission risk from horseback riding is currently higher than from football, auto and motorcycle racing, or skiing (Ball et al 2007, Mutore et al 2021). 

In assessing the welfare of animals in general it is now recognized that negative feelings (i.e., negative affective experiences) are only part of the story and that the capacity for animals to have positive affective experiences also needs to be considered (Mellor 2015a, b; 2016, 2017, 2019a, b; Mellor and Beausoleil 2017, 2019b; Mellor et al 2020). This being the case, a simple numerical assessment of riders’ negative feelings will underestimate the total benefits of removing the dominating effects of bit-induced pain unless it is explicitly understood that so doing enables the horse to have previously suppressed positive affective experiences (Mellor 2017, 2020).

If a bitted horse is trained by a rider with the hands of a neurosurgeon and the mind of a buddha, it is just conceivable that the horse will not develop many aversions to the bit. But the reality is that most riders are not master equestrians. As a result, bitted horses commonly exhibit multiple aversions to the bit and their riders commonly develop negative feelings about riding. The relevance of this is that in any investigation of, for example, pain, ridden lameness, aberrant behavior or poor performance, the bit should be considered as a possible cause and ruled-out by removing the bit at an early stage in the work-up.

Finally, on the basis of neuroanatomy, physiology and Poiseuille’s Law of aerodynamics, the hypothesis is proposed that the bit, in addition to causing pain, also causes upper airway obstruction and a cascade of consequences that include catastrophic accidents, exercise-induced pulmonary haemorrhage and sudden death (Cook 2021). The standard practice of bit usage and mandated-bit rules currently prevent such a hypothesis being tested in most horse sports. However, this does not present a barrier to change.  The rules should be changed on the sufficient grounds of the pain the bit causes. Such a change will open the way for bit-free trials to be conducted under competition conditions and for the airway obstruction hypothesis to be tested.  


In the last 20 years, a body of evidence citing the bit as a proven cause of pain and aberrant behaviour in the horse has been published.  Administrators of equestrian sport are urged to repeal competition rules that mandate poor welfare for the horse and unnecessary risk for the rider. Much as the use of helmets and body vests is to be recommended, neither of these safety measures do anything to prevent accidents from happening in the first instance.

Following the example of the Royal Dutch Equestrian Federation for dressage, it is recommended that mandatory-bit rules in all disciplines could be relaxed, perhaps on a probationary basis in the first instance, in order to enable bit-free trials to be conducted and for riders to discover an improvement in welfare and safety for both rider and horse.   

Inevitably, any questioning of the validity of a long-established standard practice like bit usage will prompt a call for further studies before action can be taken.  But there is a problem with such a requirement. Controlled experiments on randomly selected horses and riders will be difficult to design; even more difficult to fund; and are unlikely to occur. There is already ample evidence to require, on humanitarian and safety grounds, the withdrawal of any rule that mandates use of equipment that causes pain. Once mandatory-bit rules are withdrawn and riders have the option to ride pain-free, natural experiments will occur and will, it is predicted, provide an abundance of additional evidence supporting the need to discontinue bit usage.  



The authors have no conflict of interest to declare


Neither this nor the companion study would have been possible without the data provided by a pioneering group of recreational riders who switched their horse from bit to bit-free and documented the difference.   



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[1] Cummings School of Veterinary Medicine, Tufts University, North Grafton, Massachusetts, USA

Present address: 125 King Street, Cohasset MA 02025 USA. E;

[2] Washington College, Chestertown, Maryland, USA

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