Topic:Athletic Performance
Athletic performance in horses refers to the physical capabilities and endurance of horses in various equestrian activities, including racing, dressage, show jumping, and eventing. This topic encompasses the study of physiological, biomechanical, and genetic factors that influence a horse's ability to perform athletically. Research in this area often focuses on aspects such as muscle function, cardiovascular capacity, and respiratory efficiency, as well as training methods and nutritional strategies that can enhance performance. This page collates peer-reviewed research studies and scholarly articles that explore the determinants, assessment, and enhancement of athletic performance in horses.
A model equation for the prediction of mechanical internal work of terrestrial locomotion. By refining a previously published model, a simple equation for the estimation of the mechanical internal work during locomotion is presented. The only input variables are the progression speed, the stride frequency and the duty factor, i.e. the fraction of the stride duration at which a foot is in contact with the ground. The inclusion of this last variable, easily measurable, allows to obtain a single equation for both walking and running. The model predictions have been compared with the mechanical internal work experimentally obtained on humans in several conditions: speeds (range 0.8-3.3 ...
Acclimation and acclimatisation of the equine athlete. A number of studies have clearly shown that the ability of both man and horses to perform a standardised exercise test in hot humid conditions is reduced compared to that in hot dry or cool conditions (see reviews by Maughan and Lindinger, 1995; Lindinger and Marlin, 1995). In man it is clear that a period of acclimation or acclimatisation is beneficial. A search of the literature prior to 1995 indicates no published information relating to the acclimation or acclimatisation of the horse to hot or hot humid environmental conditions. Concerns for the appropriate preparation for and welfare of h...
Discrimination of mammalian growth hormones by peptide-mass mapping. Recognition by the legal authorities that growth hormones (GHs) may be abused to improve sporting performance and/or physique has led to the implementation of controls that make it an offence to produce, supply, possess or import and export GHs, with intent to supply, without the authority to do so. A method is described for the discriminatory analysis of human, equine, porcine and bovine GHs for forensic purposes. Peptide-mass mapping by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry following tryptic digestion gave sequence coverages of 97.4%, 93.7...
Characteristics of respiratory function during swimming exercise in thoroughbreds. Equine respiratory patterns during swimming were examined in five normal horses. The experiment included a preliminary warming-up stage and 6 circuits of swimming around an annular pool of a 50-meter-circumference. The horses were examined for respiratory rates, intratracheal pressures, inspiratory time (TI), expiratory time (TE), respiratory cycle (T; TI + TE), heart rates, blood lactate concentrations, hematocrit and blood gases. The respiratory rates were maintained around 25/min. Blood gas values changed significantly during swimming. The intratracheal pressures during expiration and inspi...
Incomplete oblique sagittal fractures of the dorsal cortex of the third metacarpal bone in six horses. To describe incomplete oblique sagittal dorsal cortical fractures of the equine third metacarpal bone, their surgical repair, and subsequent performance of the horses. Methods: Retrospective examination of medical records and racing performance. Methods: Six Thoroughbred race horses, 2 to 4 years of age. Methods: Radiographic confirmation of all fractures preceded general anesthesia and surgical correction. Three fractures were treated by intracortical compression using screws placed in lag fashion, and five fractures were treated by osteostixis. Race records were reviewed for each horse to de...
High thigh muscle strength but not bone mass in young horseback-riding females. To evaluate whether the type of weight-bearing loading subjected to the skeleton during horseback-riding was associated with differences in bone mass and muscle strength of the thigh, we investigated bone mass and isokinetic muscle strength in 20 female horse riders (age 17.9 +/- 0.6 years) who were riding 7.0 +/- 3.4 hours/week, and 20 nonactive females (age 17.8 +/- 1.1 years). The groups were matched according to age, weight, and height. Areal bone mineral density was measured in total body, head, lumbar spine, right femoral neck, Ward's triangle, and trochanter, the whole dominant and nond...
Electromyographic activity of the long digital extensor muscle in the exercising Thoroughbred horse. Surface electrodes were used to record electromyographic (EMG) activity of the long digital extensor muscle on the right hindlimb of 8 Thoroughbred horses for 8 s at the walk and 8 s at the trot before (unfatigued) and after (fatigued) an exercise test. The exercise test was performed on a motorised treadmill set on a 10% grade. Each test started at a speed of 6 m/s which was increased by 1 m/s each minute until the horse fatigued as indicated by its inability to keep pace with the treadmill with minimal encouragement. Observations were made on the horses prior to conditioning (untrained state...
Arthroscopic removal of palmar/plantar osteochondral fragments (POF) in the metacarpo- and metatarso-phalangeal joints of standardbred trotters–outcome and possible genetic background to POF. A clinical material of 133 Standardbred horses with palmar/plantar osteochondral fragments (POF) in the metacarpo- and metatarsophalangeal joints were studied. All horses had their fragments removed with arthroscopic surgery. 102 of the horses were 3 years old or younger when surgery was performed. Anatomical localisations of the fragments were in agreement with earlier reports. There was no statistical significant difference in month of birth in the POF--group compared to the total population. Eighty % of the horses that had raced before surgery came back to racing. The racing performance rel...
Temporary suppression of cell-mediated immunity in standardbred horses with decreased athletic capacity. Eighty Standardbred horses, originating from 5 training campuses, with decreased athletic performance in association with symptoms such as intermittent fever and mild pharyngitis were examined. As control animals, 10 horses from a stable with normally performing horses were used. Virus isolation and clinico-chemical and serological tests were performed. Lymphocyte proliferation tests were carried out to evaluate the capacity of the cell-mediated immunity. In addition, a bioassay for equine type I interferon, as a marker for early viral infections, was established. No specific microbe could be ...
Evaluation of platelet activation and platelet-neutrophil aggregates in Thoroughbreds undergoing near-maximal treadmill exercise. To determine whether platelets become activated and form platelet-neutrophil aggregates during near-maximal treadmill exercise in horses. Methods: 4 Thoroughbreds. Methods: Horses were subjected to 4 standardized exercise tests on a treadmill, and blood samples were collected before exercise, at treadmill speed of 12 m/s, and 5 minutes after exercise. Flow cytometric techniques were used to identify activated platelets, and flow cytometric and microscopic techniques were used to identify platelet-neutrophil aggregates. Results: Platelet-neutrophil aggregates increased from 2.8 +/- 0.4% at rest...
Effect of bilateral blockade of the pharyngeal branch of the vagus nerve on soft palate function in horses. To determine the effect of bilateral blockade of the pharyngeal branch of the vagus nerve on soft palate function in horses. Methods: 5 Standardbreds. Methods: Peak tracheal inspiratory and expiratory pressures and airflow were measured while horses exercised at the speeds corresponding to 75 and 100% of the speed that resulted in maximal heart rate, with and without pharyngeal branch of the vagus nerve blockade. Respiratory frequency-to-stride frequency coupling ratio was measured by correlating foot fall measurements with respiratory frequency. The pharyngeal branch of the vagus nerve was bl...
Treatments affecting fluid and electrolyte status during exercise. A number of feeding and management practices, dietary electrolyte supplements, and medications may affect fluid and electrolyte status in resting and exercising horses. The contents of the gastrointestinal tract of the equine athlete, unlike its human counterpart, are responsible for more than 10% of body weight. Although ingesta traditionally has been considered dead weight for the sprinting horse, it is a valuable reservoir of fluid and electrolytes that may be used during endurance exercise. Numerous strategies for hyperhydration of the equine athlete and for replacement of fluid and electr...
Thermoregulatory adaptations associated with training and heat acclimation. The large metabolic heat load generated as a consequence of muscular work requires activation of thermoregulatory mechanisms in order to prevent an excessive and potentially dangerous rise in body temperature during exercise. Although the horse has highly efficient heat dissipatory mechanisms, there are a number of circumstances in which the thermoregulatory system may be overwhelmed, resulting in the development of critical hyperthermia. The risk for development of life-threatening hyperthermia is greatest when (1) the horse is inadequately conditioned for the required level of physical perfo...
Fluid, electrolyte, and acid-base responses to exercise in racehorses. During both high-intensity and short-distance exercise, the high rate of expended energy is met by anaerobic oxidation of glucose to lactic acid; this is the main cause of metabolic acidosis observed during racing. In addition, plasma volume decreases because water moves from the vasculature to the intracellular and interstitial spaces at the onset of intense exercise. These fluid shifts, together with active ion-exchange between blood and tissue, cause marked changes in electrolyte concentrations. This article reviews the mechanisms of acid-base disturbances, fluid shifts, and electrolyte cha...
Effect of exercise on fluid balance and renal function in horses. Exercise places large demands on the equine cardiovascular system which are further complicated by environmental factors. In many respects, performance is limited by fluid and electrolyte stores and the ability to maintain cardiovascular and thermoregulatory stability in the face of severe sweat losses. Studies in the exercising horse have been primarily descriptive or associative, with only a limited number seeking to identify physiologic mechanisms associated with the control of fluid and electrolyte balance. More mechanistic studies are needed to fully understand the integration of the card...
Exercise of young thoroughbred horses increases impact strength of the third metacarpal bone. Exercise can have a profound effect on bone mass, but little is known of its effect on bone's material properties. In this experiment, our hypothesis was that a large difference in the training regimen of young thoroughbreds would produce a measurable difference in the mechanical properties of their bone material. When they were about 19 months old, eight thoroughbred racehorses were given one of two exercise regimens that lasted for 19 weeks: four horses (controls) were walked for 40 minutes a day but had no other exercise, and the remaining four (exercised) were additionally trotted for 20 m...
Post exercise changes in compartmental body temperature accompanying intermittent cold water cooling in the hyperthermic horse. Whereas the efficacy of cold water cooling of horses has been demonstrated by several studies, the dynamics of temperature changes within and between compartments (primarily muscle, blood [core], skin and deep core [rectal]) have not been investigated. Changes in body temperature associated with cold water cooling were investigated in the hyperthermic horse. Muscle (TMU), pulmonary artery (TPA), rectal (TREC), tail-skin (TTSK) and coat surface (TCOAT) temperatures, were monitored continuously in 5 Thoroughbred horses during and after exercise in hot humid (30 degrees C and 80% RH) conditions o...
Exercise-related alterations in crimp morphology in the central regions of superficial digital flexor tendons from young thoroughbreds: a controlled study. Injury to the core of the mid-metacarpal region of the superficial digital flexor tendon in Thoroughbred racehorses is a very frequent but poorly understood condition. It has been suggested that subclinical changes induced by galloping exercise weaken the collagen in this region of the tendon, predisposing it to rupture. The longitudinally arranged collagen fibrils in tendon follow a planar waveform, termed the crimp. Fibril bundles with a smaller crimp angle fail at a lower level of strain than those with a larger crimp angle. This study tested the hypothesis that a specific 18 month exercise...
Effect of changes in respiratory blood parameters on equine red blood cell K-Cl cotransporter. K influx into equine red blood cells (RBCs) was measured using 86Rb as a tracer for K under conditions designed to mimic the changes in respiratory blood parameters that occur in vivo during strenuous exercise. The effects on K influx of physiological changes in pH, cell volume, O2 tension (PO2), CO2 tension (PCO2), and bicarbonate and lactate concentrations were defined. Physiological PO2 exerted a dominant controlling influence on the H(+)-stimulated Cl-dependent K influx, consistent with effects on the K-Cl cotransporter, PO2 required for half-maximal activity was 37 +/- 3 mmHg (4.9 kPa). A...
Surgical treatment of subchondral cystic lesions of the third metacarpal bone: results in 15 horses (1986-1994). Subchondral cystic lesions (SCLs) in the condyle of the third metacarpal bone (MCIII) were surgically treated in 15 horses. The median age at presentation was 18 months (range 10 months-12 years) with 10 of 15 horses less than age 2 years. The SCLs were confined to the front limbs in all cases with 2 horses having bilateral lesions. Lesions were isolated to the medial condyle(s) of MCIII in 13 of 15 horses; a cystic lesion occurred in the lateral condyle in one horse and in the sagittal ridge in one horse. One horse with bilateral lesions had an additional cystic lesion located in the right me...
Laryngoplasty with or without ventriculectomy for treatment of left laryngeal hemiplegia in 230 racehorses. The purpose of this study was to examine the influence of laryngoplasty on racing performance and to determine if any of the following variables had a significant effect on outcome: breed (Thoroughbred v Standardbred), endoscopic grade of laryngeal function, ventriculectomy versus no ventriculectomy, type of prosthetic suture used, and number of prostheses placed. Methods: Retrospective study of laryngoplasty with or without ventriculectomy for treatment of left laryngeal hemiplegia in racehorses between 1986 and 1993. Methods: 230 horses (174 Thoroughbreds, 56 Standardbreds). Methods: The med...
Estimation of performance potential of standardbred trotters from blood lactate concentrations measured in field conditions. The purpose of this study was to examine the relationship between V4 (velocity which results in a blood lactate concentration of 4 mmol/l), age and racing performance of Standardbred trotters and to establish V4 normal values to select good and poor performers. The specific influence of racing (RT) and training (T1 and T2) tracks was also examined. A total of 159 horses were divided into 5 age-groups from 2 to 6 and over and performed 330 standardised exercise tests of 3 steps performed at increasing speeds. The velocity of the horses was measured with a tachometer on the sulky. Blood lactate ...
Epiglottic augmentation for treatment of dorsal displacement of the soft palate in racehorses: 59 cases (1985-1994). To determine whether epiglottic augmentation, in conjunction with more traditional surgical methods, would be useful in the treatment of dorsal displacement of the soft palate in racehorses. Methods: Retrospective study. Methods: 40 Thoroughbred and 19 Standardbred racehorses. Methods: Polytetrafluoroethylene paste was injected submucosally on the lingual epiglottic surface of each horse. In addition, sternothyrohyoideus myectomy or sternothyroideus tenectomy and staphylectomy were performed in most horses. Results: Racing performance was improved after surgery in 29 of 40 (73%) Thoroughbreds ...
The use of functional indexes to evaluate fitness in Andalusian horses. The fitness of 8 Andalusian horses between 3 and 4 years of age was analysed. The animals were subjected to an exercise test on a sandy track consisting of 2 stages of different intensities. The first stage was of submaximal intensity at 4 speeds which increased progressively (4.17, 5.56, 6.94 and 8.33 m/sec.) covering a distance of 1,000 m in each level. Between each of these speeds, the horses rested for 2 min. The second stage was a maximal speed test over the same distance carried out 2 min after the ending of the maximal phase. Data of heart rate, plasma lactate concentration, velocity, P...
Measurement of erythrocyte volumes in splenectomized horses and sham-operated horses at rest and during maximal exercise. Erythrocyte volumes of thoroughbred horses were measured. The volumes of splenectomized horses and sham-operated horses 2 hr after injection of 50Cr-tagged erythrocytes (at rest) and during maximal exercise were measured using the non-radioactive isotope 50Cr. Because splenic erythrocytes are released into circulation during exercise, it was estimated that the erythrocyte volumes of the sham-operated horses during maximal exercise are larger than those of the horses at rest. However, the erythrocyte volumes of the sham-operated horses at rest were about equal to those during maximal exercise. ...
A survey of reproductive performance in Thoroughbred mares and morbidity, mortality and athletic potential of their foals. A survey was performed to evaluate the reproductive performance of Thoroughbred mares, estimate risks of dystocia and of morbidity and mortality in foals during the first year post partum and their physical acceptability at age one year. The study population consisted of registered Thoroughbred mares and their foals owned by residents of 4 Western Canadian provinces. Owners were identified using information obtained from the North American Jockey Club, and questionnaires were mailed regarding mares bred in 1988 and their foals born in 1989. Eighty-three per cent of mares were reported to be pr...
Effects of training on the development of exercise-induced arterial hypoxemia in horses. To compare the development of exercise-induced arterial hypoxemia in horses before and after training, and to determine whether increases in maximum oxygen uptake (VO2max) following training results in a greater degree of exercise-induced arterial hypoxemia. Methods: 13 three- to five-year-old. Standardbred geldings without clinical signs of respiratory or cardiovascular disorders. Methods: Horses were rested for 4 months prior to commencing a 16-week training program. Arterial blood was collected from the transverse facial artery during standardized exercise tests performed before and after 8...