At the highest level, showjumping performance depends on many factors and requires a highly skilled and sympathetic rider with a top-class horse who is fit, healthy and appropriately trained. The successful showjumping horse must combine power, suppleness, agility and accuracy.
It is difficult to find a horse with sufficient ability to cope with modern top-level showjumping courses. It is equally difficult to keep such horses fit and well to continue to perform at the highest level over any length of time.
Compared with thoroughbred racehorses, which have been subject to a great deal of scrutiny, there has been relatively little scientific investigation of factors affecting performance in showjumping horses. At international level, they perform impressive feats of athleticism. Their preparation is crucial to their performance and, more importantly, to their health, welfare and longevity.
In a recent multinational survey of showjumping horses, it was found that 6% of training and competing days were lost for health-related reasons. Seventy eight percent of days lost were a consequence of orthopaedic conditions (those relating to the skeletal system and associated muscles, joints and ligaments), mostly comprising injuries considered by the investigators to be related to overuse.
All disciplines of equestrian sport are associated with their own spectra of likely injuries. A number of anatomical sites are commonly involved in orthopaedic problems in showjumping horses, including the foot, the forelimb flexor tendons, the suspensory ligaments, various limb joints and the back.
Showjumping horses also suffer their fair share of medical diseases. Respiratory disorders, both due to infectious causes and, probably more frequently, to allergic ones such as recurrent airway obstruction, are common.
Frequently, respiratory disease in horses is sub-clinical — that is, not obvious to the casual observer or even on a routine clinical examination. Numerous studies have shown that many horses affected by respiratory disease neither cough nor have a nasal discharge, so the absence of these signs does not preclude the possibility of underlying illness.
Specific diagnostic tests, such as examining tracheal wash samples of respiratory secretions obtained by endoscopy, are necessary to determine the presence or absence of respiratory disease with any certainty.
As well as its direct effects on performance, the presence of respiratory disease, by hastening the development of fatigue, may render an affected horse more liable to injury that may cause lameness.
Gastric ulceration is another medical condition that occurs frequently in showjumpers and all other forms of competition horse. Again, this is a condition that is usually sub-clinical (although it can be associated with a range of clinical signs, including anorexia, colic, dullness and others), but can still cause chronic discomfort. It can certainly be a reason for impaired performance.
Study sheds light
To investigate the physiological stresses of showjumping, a study was conducted recently at a British Equestrian Federation (BEF) World Class Performance training session. The study was led by the members of the BEF scientific advisory group (John McEwen, Pat Harris, Rachel Murray and the author).
Horses jumped a 1.35-1.45m course several times over a three-day period. During this time they were monitored before exercise, during warm-up and jumping, and after exercise was completed.
There were a number of interesting findings from the study, which was sponsored by the BEF’s World Class Programme. For instance, while individual riders were consistent in the way in which they warmed up their horses, there were clear disparities between riders’ techniques.
During warm-up there was a marked difference between the frequency with which horses were worked on each canter lead and the limb that they used to land over fences — the left lead predominating. If this “asymmetry” of warm-up is a common occurrence in showjumping horses, it could have significant implications for the risk of injury.
Blood lactate (lactic acid) concentrations were significantly increased over baseline values 1min after jumping. Horses with higher blood lactate concentrations then had a greater number of jumping faults, decreased jumping technique grade (as assessed by an international showjumping coach) and were more likely to show muscle soreness.
Aerobic vs anaerobic
There has been some discussion as to whether the tremendous effort of jumping requires significant anaerobic effort. This study echoed the results of others in which it has been demonstrated that horses do produce a significant amount of lactate, indicative of anaerobic effort, during jumping.
It is interesting, however, that it was the horses with the lower blood lactate concentrations that performed the best — suggesting that aerobic fitness is important in these animals as well.
Horses with higher heart rates during jumping had higher blood lactate concentrations, an increased number of jumping faults and lower jumping grade scores. They were also more likely to show muscle soreness when examined after exercise.
Horses may, therefore, have relatively higher heart rates during competition in association with jumping inefficiency and muscle pain.
Biomechanical analysis of the horses during jumping provided interesting data concerning the complex limb coordination necessary in showjumping.
This is still under analysis, but it was notable that the subjective assessment of the experienced coach was related to definable kinematic features of the jumping process.
Clearly, there is much work still to be done better to understand the physiological and biomechanical responses that occur during showjumping, the ways in which they affect performance and health and how they may profitably be modified.
It appears, however, that and reduced fatigue over the course of longer competitions.
The showjumping horse needs careful training and monitoring to perform at his best and to minimise the risk of injury.
Ref: Horse & Hound; 29 January 2015