Equine athletes: psychology and performance

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Vet Times The website for the veterinary profession https://www.vettimes.co.uk Equine athletes: psychology and performance Author : Laura Jones, Sue Dyson Categories : Equine, Vets Date : May 16, 2016 ABSTRACT The psychological characteristics associated with human athletic success and the influence different practices have on the psychological state of human athletes are well studied. The huge importance of horse and rider psychological state and the relationship between the two is wellrecognised both anecdotally and scientifically. Despite this, comparatively less evidence-based information exists regarding equine psychology and its interaction with performance and competitive success. As well as selectively breeding for desirable, often discipline-specific physical traits, we have also selected purposefully, as well as inadvertently for certain temperament traits. The psychological characteristics of horses contribute to their suitability to perform in certain disciplines and form a successful partnership with certain riders. Both motivation and arousal level at competition appear to be important factors for performance success. The presence of pain will often precipitate behavioural changes in ridden horses. The psychological state of some horses appears to be an important factor for the degree to which performance is affected by pain. To fully understand the implications of psychology on the partnership between horses and riders, and then their athletic success in the disciplines, will first require an in-depth psychological understanding of both species equally. Athletic performance at peak ability requires optimal musculoskeletal, cardiovascular and respiratory function, appropriate nutrition and correct psychological state. 1 / 11

Figure 1. Tension and high head carriage (left) assumed to be a reflection of the horse s temperament. Its way of performing is transformed by abolition of pain (right) after diagnostic analgesia to resolve subclinical lameness. Behavioural traits of horses are acknowledged as being highly important for both ease of training and management and competitive success by professional, competition and leisure riders and breeders (Graf et al, 2013). The judgement of performance in competition directly encompasses behavioural attributes. For example, the Fédération Equestre Internationale (FEI) directives for judging international young horse classes lists temperament ( attentiveness, willingness to work, natural forward-going attitude, mental suppleness ) as one of the most important aspects (Fédération Equestre Internationale, 2014). This considered, it is somewhat surprising a relative lack of evidence-based information is available on the effects of psychological state on the performance of the equine athlete. Horse psychology Basic psychological elements exist at three inter-related, but temporally separate, levels temperament, mood and emotional reaction (Goldsmith, 1994). Temperament Temperament refers to an individual s behavioural traits, which are a predisposition for an individual to act in a predictable way to the environment or a challenge. Temperament is believed to partially be a psychological phenotype, influenced by genetic factors (Hausberger et al, 2004). It is also widely regarded as being influenced by early experiences, but then remaining static within an individual. However, it is possible psychological events of a certain magnitude or significance to an individual may contribute to a modulation of temperament traits (Hausberger et al, 2004). 2 / 11

Definitions of personality traits of horses evaluated using performance tests are nebulous and do not account for confounding factors, such as rider or handler influence, environmental change and other causes of poor performance, such as pain (Pasin and König, 2013). Verbal descriptors for equine temperament lack definition and specific meaning (Mills, 1998). Mood and emotional reaction Both mood and emotional reaction, together termed affective states, are influenced by an individual s temperament, as well as environmental factors. Emotional reaction is the shortest-lived state, while mood implies a longer-lived circumstantial state. Emotional reaction is the way in which an individual will immediately evaluate and react to an environment or stimulus and, thus, is hugely influential in competitive performance in a novel environment. As well as being influenced by an individual s temperament, emotional reaction is also partially dependent on mood. For example, a negative mood state will predispose to negative emotional reactions. Equally, negative emotional reactions may contribute to the development of negative mood. This is a particularly important consideration for training and management practices during the time preceding a competition. Emotional reaction is also influenced by previous experience, emphasising the importance of training practices. Negative reinforcement comprises the majority of the training used for equine athletes, which employs aversive stimuli to discourage undesirable behaviour and its well-timed removal to encourage desirable behaviour (Innes and McBride, 2008). Positive reinforcement-based training practices tend to produce more variable responses, often with the individual providing the minimal effort required to obtain the reward. However, a positive perception of working and being ridden is important in the ridden athlete. The drive an individual horse has to work to achieve goals such as the successful avoidance of aversive stimuli and attainment of rewards is described as motivation. The degree of motivation may reflect variation of individual sensitivity to aversive stimuli and rewards. Human literature suggests high motivational characteristics may even be a prerequisite for athletic success (Anshel and Eom, 2003). Arousal 3 / 11

Figure 2. Resistant behaviour that had been assumed to be because the horse was quirky (left) is abolished (right) when pain causing subclinical lameness is resolved by diagnostic analgesia. Arousal is a physiological state involving activation of the sympathetic nervous system, which varies along a continuum, from deep sleep to extreme excitement. Although several theories exist on the relationship between arousal and performance of human athletes, the inverted U theory has been widely accepted for many decades (Yerkes and Dodson, 1908). Briefly, this theory suggests both under-arousal and over-arousal are equally detrimental to performance and an optimal degree of arousal exists for specific tasks. Building on that theory, the individual zone of optimal functioning (IZOF) model proposes optimal arousal level for peak performance varies among individuals, as well as being task-specific (or sport-specific; Hanin, 2000). Impact when competing When extrapolating this theory to equine athletes, professional competition riders already recognise a certain degree of arousal at competition can enhance performance. In addition to this anecdotal belief, some equine-specific evidence supports this (Hada et al, 2003). Should the degree of arousal exceed the IZOF, a horse can become overly excited, leading to increased energy expenditure through locomotor activity and increased distraction by external stimuli. The horse is likely to listen less to the rider s aids. This decrease in concentration and increase in energy expenditure could lead to a decrease in performance in any discipline. A horse s IZOF may also be pertinent to its success in a given discipline Dressage A dressage horse, for example, should ideally perform optimally at a relatively mildly heightened level of arousal. Emotional reactions should only be elicited by the actions of the rider, which are often subtle and require concentration on the part of the horse. Racehorses 4 / 11

At the other end of the spectrum, riders of racehorses prefer a greater degree of arousal, leading to an increased sympathetic flight response and, therefore, increased performance (Hada et al, 2003). At a racetrack, many aural and visual stimuli could drive the level of arousal towards the excited end of the spectrum. A racehorse with a low IZOF, despite having good physical capability, may exceed its IZOF and underperform at races and can, therefore, be thought of as psychologically unsuitable for this discipline. Heightened levels of excitement may lead to increased energy expenditure; so, equally, an overaroused racehorse may perform well initially in a race, but fatigue faster and fall back towards the end of the race. A horse with a high IZOF may be psychologically more suitable for racing. Eventing Eventing is a discipline that requires high level performance in three different phases, which each require a different skill set. In the dressage phase, an event horse should be relatively relaxed and listening to the rider that is, be at a relatively low level of arousal. In the cross country phase, the horse would ideally be much more aroused, ready for this faster test, as well as being somewhat responsive to both the environment and the rider to successfully navigate large, fixed fences. Event horses tend to be excitable, which is a desirable temperament trait for performance in the cross country and showjumping phases. However, for the dressage phase, these horses are often more aroused than is ideal especially because dressage is the first phase of an event and, therefore, these fit horses will be full of energy at this point, as well as being unfamiliar with their surroundings. Asking these horses to restrict their emotional reactions during the dressage test can lead to anxiety and tenseness. The use of calmers to help reduce anxiety and allow horses to adapt to new situations faster is commonplace and an abundance of marketed products are available. However, the majority of active ingredients in many products have little or, most commonly, no scientific evidence to support their efficacy. In a study, feeding magnesium aspartate reduced the reaction speed of horses (Dodd et al, 2015). However, these horses were fed higher quantities of magnesium than is available in any commercial supplements and it remains unclear whether the differences in reaction speed were indeed centrally mediated. Several studies have concluded L-tryptophan reduces aggression in a variety of species; however, this appears to be highly variable and affected by a number of confounding factors (Grimmett and 5 / 11

Sillence, 2005). A study focusing on the behavioural effects of L-tryptophan in horses actually showed mild excitation following administration (Bagshaw et al, 1994). No scientific rationale exists for feeding calcium as a calming supplement and, equally, no scientific evidence on the efficacy of B vitamins as a behaviour modulator in horses or humans. Valerenic acid (valerian) has no scientific backing and, along with L-tryptophan, is an FEI-prohibited substance. Aetiology Horse-rider relationship The relationship between horse and rider is anecdotally of huge importance in competition. Riders recognise it is often not the athletic capability of the horse that determines success, but a good working partnership between a well-matched horse and rider. Subjective assessment of horse-rider partnerships made by experienced trainers have been shown to be repeatable and consistent (Visser et al, 2010). It has been suggested a horse may sense a rider s emotional state through the rider s tension or relaxation of posture in the saddle, contact in the reins and tone of voice (Williams, 1999). A lack of scientific information exists regarding the horse-human relationship; however, the importance of rider psychology is well recognised and practised. Many riders attribute greater consistency in performance to psychological help for example, practising positivity and mentally riding the course well. One study demonstrated perception of a novel horse s temperament influences pre-competitive arousal levels of the rider and affects performance, with self-confidence being an important moderator, supporting the relationship between rider psychology and equine performance. Breeding temperaments With strategic breeding for desirable traits in horses a good example being for extravagant movement in warmblood dressage horses difficult temperaments anecdotally appear to be being selected for. These horses tend to be less naturally submissive, being more difficult to handle and train and, thus, are usually best suited to skilled professional riders. One training technique that has been used to instil submission and compliance in these horses is the hyperflexion of the horse s neck, so the chin is close to, or touching, the pectoral region, termed low, deep and round or rollkur. It is also anecdotally believed to increase hindlimb flexion, which may be a competitive advantage. 6 / 11

Controversy has surrounded the technique as, badly done, it is coercive and if the posture is maintained for excessively long periods, this may cause discomfort and negatively affect the horse s welfare. Several studies have demonstrated minimal stress associated with a hyperflexed neck position (van Breda, 2006; Smiet et al, 2014), but others indicate horses prefer to avoid this position and have demonstrated a stress response (von Borstel et al, 2009; Christiansen et al, 2014). Pain Musculoskeletal pain, or altered biomechanical function, is widely accepted as the most common cause of poor performance of equine athletes (Morris and Seeherman, 1991). Horses are motivated to avoid aversive stimuli (aids) during ridden work. If they experience musculoskeletal pain or discomfort in association with work, they can feasibly become motivated to avoid the type of work that elicits the pain. This can lead to negative affective states associated with work, which can manifest as reluctance to perform or even be tacked up, conflict behaviour, increased spookiness or compensatory/protective movement to evade painful movements (Dyson, 2015). With resolution of pain causing lameness for example, following diagnostic analgesia reluctance, spookiness and difficult behaviour associated with pain can be abolished (Figures 1 and 2), therefore strongly supporting the association between pain and behaviour in horses. Sometimes, behavioural changes when ridden are the first symptom of pain detected by riders or trainers in the absence of perceived lameness. Often, these behavioural changes are erroneously attributed to a change in psychological state, rather than as a result of pain or discomfort. Some athletes appear more able to cope with certain degrees of discomfort or pain, which may be attributed to their individual motivation to perform and succeed. In human athletes, including riders, success is synonymous with winning competitions, which, for obvious reasons, cannot directly be extrapolated to equine athletes. However, in equine athletes, the reward for performance may be the successful avoidance of negative stimuli and earning positive reward. A positive association with being ridden through previous experiences may also play a part. It is possible horses that appear to cope well with pain or discomfort are highly motivated individuals that associate ridden work with positive outcomes. We tend to find horses with a varied day-to-day work pattern and those that compete in more exhilarating disciplines, such as eventing are more likely to continue to perform well. Pain appears more likely to be detrimental to the performance of dressage horses sooner than 7 / 11

horses performing in other disciplines possibly because their training is often repetitive and performed in the same environment (arena), meaning these horses quickly become bored and are less motivated to continue performing in the presence of pain. After abolishing or ruling out pain causing poor performance, we sometimes observe some dressage horses will remain reluctant and not perform well until they are ridden outside of an arena for example, in a field. On returning to the arena, these horses will often appear hugely improved in their way of going. However, it is as yet unknown exactly why some horses appear to be able to cope with pain better than others with the same type and degree of injury. Equally, some horses will continue to perform well, despite pain, when working in their individual athletic capabilities, but when pushed to the extreme of their capabilities, will start to show behavioural changes. Stress Stress is a general term encompassing both physiological and psychological responses to novel or threatening circumstances. In temporally proximate stress, activation of the sympathetic nervous system and subsequent release of catecholamines mediates the archetypal fight or flight response, which can be beneficial to the horse to help it cope with a stressor. In chronic stress, the hypothalamic-pituitary-adrenal axis is activated, which has been shown to both impair immune responses and contribute to the progression of some types of cancer in human literature (Reiche et al, 2004). Although the role of psychological stress in horses is unclear, chronic stress has been implicated in many deleterious conditions, such as gastric ulceration, colic, recurrent exertional rhabdomyolysis, decreased growth rates and reduced reproductive capability (Vatistas et al, 1999; Gonçalves et al, 2002; MacLeay et al, 1999; Apter and Householder, 1996; Berghold et al, 2007). Correlations between heart rate, heart rate variability, behaviour scoring parameters and stress have been identified in ridden horses (Rietmann et al, 2004). Heart rate variability has been used as a measure of shifts in parasympathetic and sympathetic influence on heart rate during times of stress in humans and in horses undergoing low-intensity, non-ridden exercise (Bernardi et al, 2000; Rietmann et al, 2004). Plasma cortisol and adrenocorticotropic hormone concentrations have been shown to increase in response to competition (Cayado et al, 2006; Fazio et al, 2008). Salivary cortisol has not been clearly correlated to changes in heart rate variability in ridden horses, but was shown to transiently increase during competition (Becker-Birck et al, 2013). The same study showed an increase in heart rate during grooming and tacking up, reflecting increased sympathetic tone due to anticipatory emotional reactions, rather than physical exertion itself. 8 / 11

Change in heart rate variability and increased salivary cortisol have also been demonstrated in response to transport (Schmidt et al, 2010). The concentration of salivary cortisol was highest towards the end of transport and was higher with increasing duration of transportation. Although no studies, to the authors knowledge, demonstrate how protracted the stress response following transport is, pre-existing levels of stress at the start of competition could feasibly impact on performance. Conclusion Although clear evidence-based support exists for the importance of psychology in the performance of equine athletes, many questions are left unanswered. The interaction between horse and rider is quite unique; no other athletic sport combines the physical ability and mental state of two individuals including one separate non-verbal species. To understand the partnership first requires an in-depth understanding of the psychology of each. Improved definitions and tests for equine temperament, as well as understanding the aetiologies and effect of mood when training and at competition, are required. This will require an appreciation of the different behavioural signals displayed by horses when ridden and the circumstances under which they are displayed. This is an inevitably difficult task as countless potential confounding factors exist when considering the ridden performance horse. A tendency to anthropomorphise the behaviour and learning of horses is likely to be detrimental to understanding their motivations. For this reason, more objective data is warranted, which will also help validate the subjective judgement of behaviour and performance. References Anshel M and Eom H (2003). Exploring the dimensions of perfectionism in sport, International Journal of Sport Psychology 34(3): 255-271. Apter R and Householder D (1996). Weaning and weaning management of foals: a review and some recommendations, Journal of Equine Veterinary Science 16(10): 428-435. Bagshaw C, Ralston S and Fisher H (1994). Behavioural and physiological effect of orally administered tryptophan on horses subjected to acute isolation stress, Applied Animal Behaviour Science 40(1): 1-12. Becker-Birck M, Schmidt A, Lasarzik J, Aurich J, Möstl E and Aurich C (3013). Cortisol release and heart rate variability in sport horses participating in equestrian competitions, Journal of Veterinary Behaviour: Clinical Applications and Research 8(2): 87-94. Berghold P, Möstl E and Aurich C (2007). Effects of reproductive status and management on cortisol secretion and fertility of oestrus horse mares, Animal Reproduction Science 102(3-4): 276-285. Bernardi L, Wdowczyk-Szulc J, Valenti C, Castoldi S, Passino C, Spadacini G and Sleight P (2000). Effects of controlled breathing, mental activity and mental stress with or without 9 / 11

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