Research Paper PrePrint – Heart Rates Of Horses During Competitive Dressage
Authors: Rachel J Williams*, Rachael E Chandler and David J Marlin
Affiliations: Hartpury College, University of the West of England, Hartpury, Gloucestershire, UK. Present address, English Institute of Sport, Sheffield, Coleridge Road, Sheffield, Yorkshire, S9 5DA, UK
Publication Date:
Paper Link: To read more about, Faults in International Showjumping are not Random, then please follow this link to the full paper.
Abstract
An understanding of the physiological and metabolic demands of competition is essential for the development of training regimens that elicit adaptations appropriate for the sport being participated in. Despite the fact that dressage is a major sport and one of only three equestrian Olympic disciplines, to date there appear to be no studies that have described the heart rate of horses performing competitive dressage in any detail. The present study was therefore undertaken to describe the physiological demands of dressage competition. Thirty-five horses competing in a total of 50 dressage tests, 36 of which were at British Dressage Elementary level, and 14 at British Dressage Medium level, were studied. The horses studied were predominantly Warmblood or Thoroughbred cross geldings with an age range from 6-17 (mean ± s.d. age of 10.0 ± 2.5 years). The average duration of warm-up for all horses competing at Elementary level (n=36) was 31.3 ± 15.4 minutes and 31.4 ± 10.0 minutes for all horses competing at Medium level (n =14)(P>0.05). The mean and mean peak heart rate for horses warming-up for Elementary level was 91 ± 13 bpm and 146 ± 35 bpm, respectively and was not different to that for horses warming-up for Medium level (Mean 91 ± 10 bpm; Peak: 144 ± 32 bpm; P>0.05). The mean and mean peak heart rate for all horses while competing at Elementary level (n=36) were 102 ± 13 and 132 ± 20 bpm, respectively, and 107 ± 8 and 132 ± 10 bpm, respectively, for Medium level (n=14), and were not significantly different (P>0.05). Mean heart rates during competition were significantly higher compared with during warm-up for both Elementary and Medium levels (P<0.001). Mean heart rate during competition (Elementary and Medium data combined) was significantly correlated with mean heart rate during warm-up (r2=0.503; n=50; P<0.001). There was no association between heart rate, warm-up duration and score or placing. These observations suggest that competitive dressage at British Dressage Elementary and Medium level are only moderately aerobically demanding.
Introduction
Performance analysis is an essential tool that systematically evaluates factors identified to enhance performance to provide accurate, effective and objective feedback, which can then inform athlete decision-making with the aim of increasing future competitive success (Nicholls et al., 2018; Nelson and Groom, 2012). To be successful, performance analysis usually occurs within a defined context and is used synergistically with the athlete, their coach and performance analyst using the information gained to inform skill development, design training regimes and competition strategies aligned to periodization and performance targets (McGarry, 2009). Once a defined goal is set, the performance analyst will aim to describe, explain and predict the athlete’s performance by identifying associations between sport-specific behaviours (actions) and outcomes (key performance indicators or goals), whilst considering the influence of extrinsic variables, such as other competitors and the environment, to develop performance improvement strategies (McGarry, 2009; Williams, 2013).
Performance analysis can be used within training to assess athlete progress or within competition environments to reflect on the success of competition strategies and to analyse specific aspects of athlete performance (Williams, 2013). Traditionally, human sports feedback involved subjective observations based predominately on an athlete’s coaches’ perceptions and experiences (Maslovat and Franks, 2015). Unfortunately, the success of using subjective observations to inform training and competition strategy development is reliant on the ability of the athlete’s or coach’s memory recall, which is reported to at best to be ~50% (Nicholls and Warsfold, 2016; Laird and Waters, 2008). How athletes can access feedback is changing through the advent of technology and the increased implementation of performance analysis techniques enabling coaches and the athletes themselves to review and analyse multiple facets of an individual or team performance. The effectiveness of applied performance analysis has been documented in football and rugby. Studies have demonstrated the use of a performance analyst and coach combination, using video analysis techniques aided athlete recall, encouraged self-critique, expedited unemotional reflection on their performance and improved player confidence as well as changing athlete behaviour (Groom and Cushion, 2004; Francis and Jones, 2014). Performance analysis should therefore be considered a fundamental tool to facilitate athlete learning and development, and competitive success.
Despite the widespread uptake of performance analysis across human sports, its application within equestrianism is still in its infancy. The welfare of the horse is becoming an ever more important focus across all horse sports (Waran and Casey, 2005) leading to increased calls for the application of evidence-based practice. Performance analysis techniques can provide an approach that encourages professionals to use the best evidence possible when making decisions about the methods, treatments and actions employed to achieve their performance goals whist concurrently safe guarding the welfare of the equine athlete (Waran and Randle, 2013). However equine performance analysis traditionally focuses on subjective assessment of performance through observation or ‘feel’ (Williams, 2013; Ely et al., 2010) concepts that are subject to individual perception, bias and rely on memory recall rather than being evidence based. Analysing performance in equestrianism is also complex, requiring focus on the individual performance characteristics in the horse (influenced by the rider), the rider (which can be influenced by the horse), the horse and rider as a partnership, and the ‘performance’ as a holistic entity (Williams, 2015). This is complicated further by the reliance on self-analysis required as many equestrian partnerships train in relative isolation compared to equivalent partnerships in human sport. Parallels could be drawn with this complexity to the dynamics which exists in team sports in the human field, where performance analysis techniques have proved successful (Groom and Cushion, 2004; Francis and Jones, 2014). Scope therefore exists to apply performance analysis techniques across equestrian sport to gather objective data that will add to the developing evidence base to enable riders, trainers and coaches to make informed decisions to enhance equine performance and welfare.
Showjumping is the most popular equestrian sport amongst the Fédération Equestre Internationale (FEI) disciplines (FEI, 2017; Gorecka-Bruzda et al. 2013). Yet despite this, little research contextualised to performance analysis for the sport exists (Williams, 2013; Murphy et al. 2009). The key aim of the sport is for horse and rider combinations to complete a course of jumping obstacles within a defined time or in the fastest time without scoring any penalties (faults). A successful elite showjumping horse needs to have superior physical abilities to be able to jump and clear successfully various fence types of heights up to 1.60m and widths of 2.00m for oxers (a fence with 2-3 rails or poles that may be set at the same or different heights), 2.20m for triple bars and up to 4.50m for water jumps (FEI, 2017). As well as possessing a suitable temperament to facilitate ‘rideability’ (Visser et al., 2003) and sufficient fitness to meet the physiological demands of the competition (Williams, 2015). Tactics are a central component of success in sport (Rein and Memmert, 2016) including showjumping with riders determining the speed and approach their horse takes to fences. Therefore, implementing an effective competition strategy in the ring is essential to enable optimal performance (Williams, 2013; Sampaio and Macas 2012).
Accruing faults is a key negative performance indicator in showjumping. It is commonly believed by showjumping riders and trainers that faults do not occur by chance, but are associated with particular types or location of fences. This study aimed to use notational analysis, a performance analysis technique designed to assess competition strategies (Duthie et al., 2003), to characterise faults as defined by the FEI (knocking down a fence pole/rail/plank, displacing an obstacle, a foot landing in a water jump, refusal or “run-out”). The hypothesis was that faults at elite level showjumping are not random.
Materials & Methods
Competition venues
Horses performing Elementary and Medium level dressage were monitored at six different competition venues affiliated to British Dressage (BD) throughout January and February in a single year (Table 1). The arenas used for warm-up and competition, including the surface type, are described in Table 1.
Sample population
Thirty-five horses performing dressage under British Dressage (BD) rules and competing in a total of 50 dressage tests, 36 of which were Elementary level, and 14 Medium level, were studied. None of the BD tests at elementary or medium levels include collected movements. The horses were selected only on the basis of competing at Elementary or Medium level and with agreement of the owner/rider to take part in the study. The overall study group consisted of 78% geldings and 22% mares, belonging to the following breeds: 47% Warmblood, 36% Thoroughbred cross and 17% Thoroughbred. Ages ranged from 6-17 years with a mean ± s.d age of 10.0 ± 2.5 years. The average height of the population was 16.1hh, ranging from 15hh to 17.1hh. A total of 36 dressage performances were monitored in horses performing one of six different Elementary level tests (see Table 1). A total of 14 dressage performances were monitored at Medium level and comprised 3 different tests (see Table 1). Horses were monitored while performing their entire warm-up and throughout the duration of the dressage test.
Dressage Test Characteristics
For the BD Elementary level tests studied, there was an average of 300 marks awarded for the movements performed, of which 14% were awarded for walk, 48% for trot and 38% for canter. The BD Medium level tests studied were similar, having an average of 330 marks awarded for movements, with 14% awarded for walk, 49% for trot and 37% for canter. BD Elementary tests require horses to perform collected, medium and extended walk, trot and canter, walk pirouettes, simple changes through walk, rein back and shoulder-in, travers, renvers and leg yielding (all at trot). Medium tests are essentially the same but with the addition of half-pass in trot and canter. Higher level medium tests also require collected canter entry to halt at x. The average stated duration for the tests at Elementary and Medium level were 5.36 and 5.33 minutes, respectively. Tests were either performed in a 20m x 40m or 20m x 60m arena for Elementary but only in a 20m x 60m for Medium level tests.
Data Collection
A single digital video camera (Sony Digital DCR-TRV80E PAL) was used to obtain video recordings of each dressage test. The camera was placed on a tripod near to the dressage judge at ‘A’ (point of entry into the arena on the middle of one short side of the rectangular arena) or ‘C’ (directly opposite the arena entrance on the other short-side of the arena) to enable a recording to be obtained that matched the view of the judge as best possible. Recording started as the horse entered the arena before the bell rang, and the horse was kept in view throughout the duration of the test and recording was terminated as the horse left the arena.
Heart rate recordings were made using Polar S610 horse trainer heart rate monitors set to record in 5 second averaging mode, T52H coded transmitter and electrodes (Polar, Bodycare Products, Southam, UK). The two electrodes of the heart rate monitor were fitted underneath the horse’s girth; one was placed slightly to the left of the ventral midline and one at the middle of the thorax on the left hand side, directly beneath the girth straps. The coat under the electrodes was dampened and electrode gel was applied to the electrodes to ensure a good contact. The transmitter was attached to the left ‘D’ ring at the top of the horse’s saddle. The receiver unit was placed on the rider’s left wrist. A stopwatch was started at the same time as the stopwatch function on the heart rate monitor in order to relate the movements of the horse in the arena to the video and the heart rate recordings. The data stored in the receiver was downloaded to a laptop using a Polar infrared interface for analysis with the Polar Precision Performance 3.0 programme.
pies of dressage score sheets were obtained for all horses that were studied. Overall scores for the tests as well as placing within the competition were recorded.
Data handling and analysis
Markers were applied to the data using the Polar Precision 3.0 programme to allow the warm-up data to be separated from competition data. The data was then transferred to Microsoft Excel 2000 for further analysis. The peak heart rate and mean heart rate ± standard deviation (sd) was calculated for each individual horse, during warm-up and competition. The peak and mean heart rate (± sd) were then calculated for all horses performing either elementary or medium level dressage tests and for all horses in all tests. The proportion of time, expressed as a percentage, horses spent at different ranges of heart rates for the duration of warming-up and competition were calculated.
The video recording was transferred to VHS tape. Any extremes in heart rate during the test were then checked against the video recording to attempt to determine if aberrations were due to extreme movement (e.g. “spooking”) or equipment failure (e.g. loss of contact).
Statistical analysis
The Kolmogorov-Smirnov test (SPSS version 12.0) was used to determine if data was normally distributed. Microsoft Excel was used for all subsequent statistical analysis. A level of P<0.05 was considered significant. Differences between warm-up and competition heart rates were investigated using a two-sample paired T-test. A two sample F-test was used to confirm that the variance in heart rate and warm-up duration between elementary and medium were similar. Subsequently, an unpaired T-test assuming equal variances was used to investigate differences between elementary and medium variables.
A one-way analysis of variance (ANOVA) was used to investigate differences between the different dressage tests at elementary level. ANOVA was not used at medium level because one of the tests (Medium 75) only contained one horse. An F-test was therefore used for medium level, followed by a T-test (two sample assuming equal variances).
Pearson’s correlation coefficient was used to investigate the relationship between heart rate during warm-up and that in subsequent competition, and the relationship between heart rate and score.
Results
Warm-Up
Mean warm-up and peak warm-up heart rates were not different between the different Elementary tests (P<0.05). Warm-up duration was significantly different (P<0.01) between horses warming-up for the different Elementary tests, ranging from 18 ± 7 minutes for Elementary test 56 to 53 ± 17 minutes for Elementary test 41 (See Table 1). At Medium level, there was no significant difference (P>0.05) in mean warm-up or peak warm-up heart rate between the different medium level tests. Warm-up duration was not significantly different between the different Medium level tests (P>0.05).
The distribution of heart rate values were normally distributed for horses warming-up and competing at Elementary level dressage. During warm-up 65.2% of the time was spent at heart rate values in the range of 80-160 bpm of which 54.5% was 80-120 bpm, and only 1.3% of time the heart rate values exceeded 160 bpm. At Medium level, over 69.7% of the time heart rate values for horses warming-up were in the range 80-160 bpm, of which 54.7% was between 80 and 120 bpm. There were no heart rate values that exceeded 160 bpm.
The average duration of warm-up for all horses competing at Elementary level (n = 36) was 31.3 ± 15.4 minutes and 31.4 ± 10.0 minutes for all horses competing at Medium level (n = 14)(P>0.05). The mean and mean peak heart rate for horses warming-up for Elementary level was 91 ± 13 bpm and 146 ± 35 bpm, respectively and was not different to that for horses warming-up for Medium level (Mean 91 ± 10 bpm; mean Peak: 144 ± 32 bpm)(Figure 1). There was no significant difference in mean or mean peak warm-up heart rates between Elementary and Medium level (P>0.05).
Competition
There was no significant difference in mean or mean peak heart rate between the different individual tests at Elementary level or between individual tests at Medium level (P>0.05).
In competition at Elementary level, 82.7% of heart rate values recorded were in the range 80-160 bpm, 69.7% of which were between 80-120 bpm and only 0.2% of heart rate values exceeded 160 bpm. At Medium level, 83.8% of the time the heart rate values for horses competing were between 80 and 160 bpm, 55.9% of which was between 80-120 bpm. No heart rate values were recorded above 160 bpm during competition.
The mean and mean peak heart rate for all horses while competing at Elementary level (n=36) were 102 ± 13 and 132 ± 20 bpm, respectively, and 107 ± 8 and 132 ± 10 bpm, respectively, for Medium level (n=14)(Figure 1). There was no significant difference between mean or peak competition heart rates between the two levels (P>0.05).
Mean heart rates were significantly higher in competition compared with during warming-up for both Elementary and Medium levels (P<0.001; Figure 1). In contrast, peak heart rates during warming-up were significantly higher than peak heart rates in competition at Elementary level (P<0.05; Figure 1) but not at Medium level (P>0.05).
Repeatability of measurements during competition at the same level
Eight horse and rider combinations competing at Elementary level and 4 at Medium level were monitored on two separate occasions at different competitions during the study. For these horses there was no significant difference in mean warm-up heart rate (Test 1: 89±11 versus Test 2: 94±9 bpm; P>0.05), mean peak warm-up heart rate (Test 1: 146±28 versus Test 2: 136±20 bpm; P>0.05), mean competition heart rate (Test 1: 105±8 versus Test 2: 106±9 bpm; P>0.05) or mean peak competition heart rate (Test 1: 141±21 versus Test 2: 133±11 bpm; P>0.05).
Relationship between heart rate and score
Mean heart rates for horses that achieved the highest scores in competition were very variable, ranging from some of the lowest (79 bpm) to the highest (131 bpm) heart rates recorded. There was no correlation between heart rate and dressage score awarded at either Elementary or Medium level (P>0.05), nor when the data between the two levels was pooled (P>0.05).
Relationship between heart rate during warm-up and competition
There was a significant positive correlation between mean heart rates of horses warming-up and in competition for both Elementary and Medium dressage tests combined (P<0.01; Figure 2). A significant positive correlation was also seen for both Elementary (r2=0.523; n=36; P<0.01) and Medium level tests (r2=0.568; n=14; P<0.01) individually.
Discussion
Potential limitations of the present study
A potential limitation of this study is the use of heart rate to estimate workload as heart rate during exercise below values of ~160bpm are known to be susceptible to elevation due to anxiety/excitement separate from effort per se. However, examination of the individual heart rate recordings suggested that this would have been minimal as all horses showed similar trends throughout the individual tests. However, the higher heart rates in competition compared with in warm-up may be due to some component of anxiety and or excitement as dressage riders frequently perform similar movements in warm-up as they will be doing in subsequent competition. However, the duration of warm-up is longer and the movements are generally not performed in as concentrated time period as during real competition.
Test characteristics of elementary and medium level dressage
Understanding the physiological demands of dressage tests and how riders warm-up for them may enable the rider and or coach to tailor training to best suit the demands of the competition through identification of aspects of the performance that contribute most significantly to marks awarded, enabling specific preparation to occur for each competition to improve the chance of a success. Coaches of human athletes constantly strive to improve performance and it is well documented that when appropriate feedback is provided motor skill acquisition improves significantly (Schmidt and Lee, 1999). Of course in equestrian sport, the feedback is to the rider who must then in turn apply this to the horse.
In both the elementary and medium level dressage tests studied, trot was found to be the most influential gait in relation to the amount of marks awarded (48% and 49% respectively), with canter being the second most important (38 and 37% respectively) and walk contributing the least to the marks awarded (14% in both levels). Training and competition preparation should therefore be aimed mainly at improving the trot and the canter and movements within these gaits to achieve optimal marks in competition.
Very little work has been undertaken in the sport of dressage in contrast to other disciplines, for example endurance or eventing. Clayton (1989) looked at the physical requirements of a Grand Prix test and found that low intensity exercise of slow speed duration contributed 88% of the marks in the test and that movements performed in the faster gaits contributed only 12%.
Identification of the percentage of marks awarded for specific dressage gaits and movements in individual tests can easily be identified by the rider/trainer enabling training to be tailored to a specific competition, with the aim of improving performance. Identification of dressage tests the horse is most likely to perform well in depending on its natural ability and expressiveness of the gaits can then be made, which would enable competitors to chose competitions to best suit the individual horse and its current progress through training.
The average duration of the elementary (5.36 min) and medium (5.33 min) level tests in the present study is similar to that reported by Clayton (1993) for Canadian dressage basic level tests of 4.50 minutes and medium level tests of 6.17 minutes.
The stated duration of the dressage tests at elementary level increase progressively throughout the test series in the sample of tests investigated in the present study (4.30, 5.00, 5.30, 5.40, 5.30 and 6.00 min). As the horse progresses it is required to perform for longer as well as performing more difficult movements. Training for specific tests should therefore mimic this pattern to ensure the horse is adequately conditioned to perform for the required period of time, without becoming physically or mentally fatigued. From a training point of view, Clayton (1993) suggested that horses should be trained in concentrated periods of work approximately equal to the duration of the test, with rest intervals in between. On the basis of the data in the present study it would seem appropriate to focus on the requirement for movements at a higher level before attempting to increase the ability of the horse to work for longer durations when progressing from elementary to medium level.
Warm-up duration
Competitors at both elementary and medium level warmed-up for an average total duration of 31 minutes, with a greater variation in duration at elementary level. This may be a reflection of riders competing at this level ranging from low to high levels of experience. The duration of warm-up appears to be appropriate based on suggestions that ~20 minutes is required to initially warm-up prior to undertaking more strenuous work (Lindner, 2002). However, the structure of warm-up was not recorded in the present study and it could be that riders undertook strenuous movements early on in the warm-up period before the horses were appropriately warmed-up. This may be one explanation for the higher peak heart rates observed in warm-up compared with competition. The duration of warm-up in the present study is also similar to that previously reported by Murray et al (2006).
For the horse to achieve optimal performance in competition, it is common practice for competitors to practice movements during their warm-up that are contained within the test. The duration of warm-up suggests some competitors may not be allowing sufficient time to warm-up the horse prior to commencement of these more strenuous movements. Low-intensity warm-up in a training environment prior to undertaking more strenuous movements has previously been reported to last for a duration of 20-30 minutes (Lindner, 2002).
Warm-up of short duration may effect performance of individual horses. Correct warm-up should promote freedom of movement through relaxation and stretching (Clayton, 1991). Interestingly, Murray et al (2006) recently reported that both increased warm-up time and specific warm-up design were positively (but weakly) associated with final score at novice and Prix St Georges level.
Mean and Peak heart rates at elementary and medium level
The only previous studies performed on the heart rate response to pure dressage (i.e. dressage as an individual discipline) were conducted in a training environment (Clayton, 1989; Lindner, 2002). The findings of the present study are, to the best of our knowledge, the first published information on the heart rate response of horses during dressage.
The mean and peak heart rates for horses warming-up and competing at both levels was found to be in the range 70 to 160 bpm, suggesting that at a whole body level these horses are working almost entirely aerobically. However, it is speculated that individual muscle groups are worked intensely and possibly transiently rely on anaerobic glycolysis. The fact that no difference was seen between elementary and medium level may indicate these horses were sufficiently conditioned to meet the physical demands of the increased difficulty of movements at medium level. Alternatively, the lack of difference could be due to other factors such as insufficient warm-up, fitness (Fregin and Thomas, 1983; Piccione et al. (2000), breed (Cikrytova et al. 1991) or age (McKeever and Malinowski, 1997) of horses at the different levels.
During competition the mean heart rate for elementary and medium level dressage were 102 and 107 b.p.m., respectively. Lindner (2002) reported the mean heart rate value for horses performing dressage exercise in a training environment to be 120 bpm, which is higher than found in the present study.
The only previous report in the literature for heart rates during dressage competition was a mean of 92 bpm in event horses competing in a one star three-day event, which is considerably lower than the mean values seen in the present study, even though the event horses were competing in temperatures of 33°C (Marlin et al. 2001). Exercise in thermally challenging environments will increase the degree of thermoregulation (e.g. skin blood flow, ventilation, heart rate, sweating) and consequently, increase heart rate. Explanations for the differences may be a higher level of fitness in the event horses and differences in breed.
Relationship between heart rate in competition compared to warm-up
Mean heart rate in this sample of elementary and medium level dressage horses was found to be greater in competition than when warming-up. Heart rates may be higher in competition due to the effects of excitement or anxiety, as heart rates below ~150-160 bpm are most susceptible to the effects of adrenaline (Hamlin, 1979; Erickson et al. 1991). Alternatively, it may be that movements are performed with more intensity during competition. There is also the possibility of increased heart rate during competition as a result of cardiac drift through increased body temperature (Thomas and Fregin, 1990) as a result of warm-up. Another possibility is elevation of heart rate as a result of development of progressive fatigue. For example, when the same movement is performed twice in a dressage test, the heart rate has been observed to be higher the second time the movement is performed (Fielding, Geering and Marlin, unpublished data).
Mean heart rate during warm-up was significantly positively correlated with mean heart rate during competition. Three horses particularly stood out in the sample of horses at elementary level, where their heart rate in competition was considerably higher than when warming-up. All three horses were studied at a single venue (Radway), where the warm-up area was inside but the competition arena was outside; at all other venues the competition arena was inside and at all but Hartpury the warm-up was outside. The heart rate of the horses at Radway may have been elevated in response to the weather, which was particularly windy, or distractions from performing outdoors.
The competing surface may also have had an effect on the heart rate of the horse studied, For example, Sloet van Oldruitenborgh-Oosterbaan et al. (1991b) reported that the heart rates of vaulting horses could be raised by as much as 50% when cantering in deep sand. However, surface alone is unlikely to explain the elevations in the horses at Radway as the surface was of a similar type to several of the other venues studied. Interestingly, in the case of two of the three horses with the highest heart rates they were observed to be poorly performing, where one horse had the lowest score out of all (n=50) horses studied. From analysis of the video footage for this horse it could clearly be seen the horse was tense and “spooking”, possibly accounting for the low score and high heart rate.
Two data points particularly stood out at medium level as being a higher than expected heart rate in competition from the value recorded during for warm-up. Both data points were from the same horse, which had the same warm-up heart rate (95 bpm) for both tests; this horse performed, well being the 5th and 7th most highly performing horse in the sample (n=50).
The heart rates recorded in the present study show these horses are working as hard, and in some cases harder, than the Grand Prix horse studied by Clayton (1989) during training where heart rate values ranged from 62-141 bpm. This assumes that heart rate is a reliable indicator of workload and may not be for reasons already highlighted. Alternatively, the horses at Grand Prix level whilst performing more difficult and or intense movements and for a longer duration may either be fitter or athletically superior to those in the present study (Clayton, 1991), However, this makes the assumption that heart rate in Grand Prix horses is the same during competition as during training. Based on the present study this may not be the case.
Heart rate and warm-up durations for individual dressage tests
There were no statistically significant differences between mean or peak heart rates for the different tests at either level, although it is difficult to be certain if this is due to the relatively small numbers of horses studied in individual tests. However elementary test 41 stood out as having a higher mean heart rate of 112 bpm compared with other elementary tests. This was a surprising finding as this test is the shortest duration and the first test in the elementary series. As discussed above, this could be due to the warm-up and arena locations. Alternatively however, when the requirements of the test are examined it is apparent that elementary 41 has a higher proportion of marks awarded for canter (47%) than the other five tests studied at elementary level, and also has a corresponding lower than average proportion of trot (41%) and walk (12%). Thus, it is not unexpected that horses may have to work harder in this particular test.
One possible conclusion from the warm-up observation is that some riders may not allowing sufficient time for the horse to physically warm-up and to subsequently perform specific movements in preparation for the test. They may also be progressing too rapidly from light to intense warm-up in order to focus on specific movements, possibly increasing the likelihood of injury. Murray et al. (2006) observed that mean warm-up duration only increased from around 25 min at novice level to around 34 min at Prix St Georges level. As the movements are more demanding and the length of the test longer at Prix St Georges, one could speculate that either riders at the lower levels are warming-up for too long or that riders at the higher levels are not warming-up sufficiently.
Heart rate characteristics for individual horses competing in more than one test
In general in the present study in a limited number of horses. heart rate characteristics, for both warm-up and competition appear to be very repeatable between dressage tests of the same level. This suggests that it may be possible to monitor individual horses training and performance in dressage over time using the heart rate response to warm-up and competition.
Relationship between heart rate and performance in individual horses
Looking at the whole sample of horses studied, there was no indication that there was a simple relationship between heart rate and performance. The horses that scored highest in competition in this study varied greatly in their heart rate values. One horse had the lowest mean heart rate value in competition (79 bpm). One potential reason for this exceptionally low heart rate for this level of work could relate to the fitness of the horse, as this horse was an advanced eventer being prepared for Badminton CCI**** (four-star level) Horse Trials. In addition, this horse was being ridden by an elite rider. All the other horses in the group of highly scoring horses were dressage horses aged 6-8 years and Warmblood breeding, all of which were ridden by experienced riders.
In the case of dressage the quality of the gaits is likely to have the most influence on the scores achieved in competition, perhaps irrespective of the effort required to achieve the movements. What may be more useful is to establish baselines for the heart rate responses of individual horses over time and to relate heart rate to the ability to perform specific movements rather than the overall performance.
In conclusion, heart rate in warm-up was related to heart rate in competition, but heart rates in competition were generally lower than those recorded in warm-up. Higher heart rates in competition were not associated with higher marks.
Further studies are indicated to examine how heart rate response to competitive dressage changes over time within tests and in relation to different movements and with higher levels of competition above those studied here.
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Table 1 Competition venues used for data collection and surfaces of warm-up and competition arenas.
| Competition venue | Dressage tests monitored | Warm-up Arena | Competition Arena |
| Hartpury College | Elem 56 (n=1) | Indoors Peat and rubber strips | Indoors Peat and rubber strips |
| Radway Riding School | Elem 41 (n=3), Elem 56 (n=3) Med 61 (n=1) and Med 75 (n=1) | Indoors Peat | Outdoors Silica sand |
| West Wilts Equestrian Centre | Elem 52 (n=6), Med 61 (n=4) and Med 74 (n=4) | Outdoors Silica sand and rubber | Indoors Silica sand and rubber |
| Hand Stadium Equestrian Centre | Elem 52 (n=3), Elem 56 (n=4), Med 61 (n=2) and Med 74 (n=2) | Outdoors Sand and rubber | Indoors Peat |
| Kingswood Equestrian Centre | Elem 52 (n=2), Elem 55 (n=3) | Outdoors Silica sand and rubber | Indoors Silica Sand |
| Huntley School of Equitation | Elem 44 (n=5), Elem 51 (n=6) | Outdoors Sand | Indoors Peat |
Figure 1. Mean (±SD) heart rate (top panel) and mean (±SD) peak heart rate (bottom panel) in warm-up and competition in horses competing in Elementary (n=36) and Medium (n=14) dressage competition. Competition significantly different from Warm-up * P<0.05 *** P<0.001
Figure 2. Mean heart rate during competition as a function of mean heart rate during pre-ceding warm-up in horses competing in Elementary (n=36) and Medium (n=14) dressage competitions (combined datasets). – – – = line of identity.
