Topic:Athletic Horses
The topic of athletic horses encompasses the study and analysis of horses that are trained and conditioned for performance in various disciplines such as racing, show jumping, dressage, and eventing. These horses are subject to specialized training regimens and nutritional plans to optimize their physical capabilities and performance outcomes. Research in this area often focuses on aspects such as biomechanics, cardiovascular fitness, muscle physiology, and injury prevention. This topic includes a collection of peer-reviewed research studies and scholarly articles that explore the physiological adaptations, training methodologies, and health management practices associated with maintaining and enhancing the performance of athletic horses.
Production of reactive oxygen species in neutrophils after repeated bouts of exercise in standardbred trotters. Six trained Standardbred trotters exercised on a racetrack on 2 days with a 3-day interval. On both exercise days the horses trotted three different exercise bouts with increasing intensity with 60-min intervals. Exercise-induced stress was manifested as leucocytosis, an increase in the neutrophil:lymphocyte (N:L) ratio, and increased capacity to produce reactive oxygen species in the peripheral blood as indicated by an increase in whole blood chemiluminescence. The leucocytosis was mainly due to neutrophilia, which lasted for 6 h. Production of reactive oxygen species per single neutrophil sh...
Subchondral cystic lesions of the proximal extremity of the tibia in horses: 12 cases (1983-2000). To determine clinical and radiographic features of subchondral cystic lesions (SCL) of the proximal extremity of the tibia in horses that could be used to classify these lesions as being related to osteochondrosis or osteoarthritis and to evaluate results of surgical debridement. Methods: Retrospective study. Methods: 12 horses with 14 SCL. Methods: Medical records and radiographs obtained before and after treatment were reviewed. Results: In 6 young horses (8 lesions), SCL were considered to be related to osteochondrosis; all involved the lateral tibial condyle. The remaining 6 horses were ma...
Contact areas and pressure distribution on the proximal articular surface of the proximal phalanx under sagittal plane loading. The objective of this study was to map topographically contact areas and pressure distributions on the proximal articular surface (PAS) of the proximal phalanx (PI) under various clinically relevant loading conditions. Left and right forelimbs of 13 mature horses were transected halfway down the radius and loaded in a position mimicking the weightbearing attitude close to the midstance phase. Five loads were used which corresponded with loads that can be expected in different gaits or during athletic performance (stance: 1800 N, walk: 3600 N, trot: 5400 N, gallop: 10,500 N and jumping: 12,000 ...
Evaluation of an in-shoe pressure measurement system in horses. To develop an objective, accurate method for quantifying forelimb ground reaction forces in horses by adapting a human in-shoe pressure measurement system and determine the reliability of the system for shod and unshod horses. Methods: 6 adult Thoroughbreds. Methods: Horses were instrumented with a human in-shoe pressure measurement system and evaluated at a trot (3 m/s) on a motorized treadmill. Maximum force, stance time, and peak contact area were evaluated for shod and unshod horses. Three trials were performed for shod and unshod horses, and differences in the measured values were examine...
Colic surgery in 206 juvenile thoroughbreds: survival and racing results. The purpose of our study was to determine the types of lesions that cause colic in juvenile Thoroughbreds, factors associated with these lesions and the subsequent survival and athletic performance of the juveniles. The age of juvenile Thoroughbreds requiring surgical exploration for abdominal pain has an influence on the type of lesion causing colic. The short-term survival rate (discharge from the hospital) after colic surgery for foals was 85% and was strongly influenced by the lesion causing colic. Thirteen percent of juveniles recovered from the first surgery experienced another severe co...
Role of exercise and ascorbate on plasma antioxidant capacity in thoroughbred race horses. During exercise, the oxygen consumption and the production of free radicals increase and can lead to oxidative stress with a deleterious effect on cellular structures involved in physical activity. To evaluate the oxidative stress produced by exercise and the role of ascorbate as an antioxidant, venous blood samples were obtained from 44 thoroughbred racehorses, before and after a 1000+/-200-m race at maximum velocity. Fourteen of these horses were treated intravenously with 5 g of ascorbate before running. Antioxidant capacity (PAOC), endogenous and exogenous ascorbate concentration, total an...
Changes in cardiac dimensions and indices of cardiac function during deconditioning in horses. To investigate the effects of deconditioning on cardiac dimensions and indices of cardiac function in horses. Methods: Thirteen 3-to 4-year-old Standardbred geldings. Methods: All horses had echocardiographic measurements performed at the conclusion of 9 months of intense training and at weeks 1.5, 4, 8, and 12 of deconditioning. Direct echocardiographic measurements included interventricular septal thickness, left ventricular internal dimensions, left ventricular freewall thickness, left atrial dimension, aortic diameter, diameter of the pulmonary artery, slopes of the mitral valve, heart rat...
Reliability of two 2,400-m time-trial protocols for assessing performance of Standardbred racehorses. To evaluate the reliability of 2 time-trial protocols, 1 that involved use of a pacemaker and 1 that did not, for assessing performance of Standardbred racehorses. Methods: 3- to 7-year-old Standardbred maiden pacers. Methods: 11 Standardbred pacers were used to determine the reliability of a time-trial protocol that involved use of a galloping pacemaker. All tests were performed by a single driver. Horses were paced for an initial 1,600 m then raced and timed for the final 800 m. They were retested 9 days later. Twenty-two horses were used to determine the reliability of a time-trial protocol...
Reduction of renal function in exercising horses. Glomerular filtration rate (GFR) and extracellular volume (ECFV) were measured before, during and after treadmill exercise in 5 trained Thoroughbred horses (mean weight 483 kg). GFR/ECFV was determined by plasma disappearance of Tc-DTPA and ECFV was measured independently as thiocyanate space. Resting GFR averaged 1.6 l/min (3.3 ml/kg/min) and fell by over 40% during exercise, moreover the fall was severe even during the first walk, prior to trotting. The results suggest that rather than being protected, GFR is allowed to fall, even with mild exercise and that this is probably an adaptation to...
Body centre of mass movement in the sound horse. The body centre of mass (BCM) is a key factor in the analysis of equine locomotion, as its position and movement determines the distribution and magnitude of loads on the limbs. In this study, the three-dimensional (3D) movement of the BCM in walking and trotting horses was assessed using a kinematic, segmental method. Thirty markers representing 20 body segments were recorded in 12 sound horses while standing, walking and trotting on a treadmill using a high-speed video system. Based on segmental inertial data, 3D positions of the segmental centres of mass as well as the total BCM were calcul...
Physical, hematological, and exercise response of collegiate female equestrian athletes. Physiological testing is extensively used to assess current physical status, target strength/deficiencies, and determine predisposition to injury in athletes. No studies exist regarding these issues on equestrian athletes. The purpose of this study was to quantify the physical, hematological, and exercise response of female equestrian athletes in order to provided greater insight into the health fitness of this unique competitor, and to compare results to other better studied sport athletes. Methods: Following written informed consent, physiological assessments were performed on 24 collegiate ...
Hematological changes and athletic performance in horses in response to high altitude (3,800 m). This study had two goals: 1) measure hematologic changes with high-altitude acclimatization in horses; and 2) assess the effect of 9 days at high altitude on subsequent athletic performance at low altitude. Six horses performed standardized exercise tests on a dirt track (before and during time at altitude) and treadmill (pre- and postaltitude exposure). Resting and immediate postexercise blood samples were measured for blood volume, lactate, red cell number, packed cell volume, and 2,3-diphosphoglycerate (DPG) concentrations at 225 m, over a 9-day period at 3,800 m, and shortly after returnin...
[Energy and protein supply for event horses during training: comparison between intake and requirements]. In horses that exercise intensively (for example, event horses in training) the intake and energy requirements were compared on the basis of a diet record and estimates of energy required for exercise. Daily net energy intake over a 7 days period was on average 30% (n = 15) higher than the net energy requirement. Since the horses had a constant body weight, and thus were in energy balance, the energy intake was overestimated and/or the energy requirement was underestimated. The intake of digestible protein was 92% higher than the protein requirement. This study illustrates the problems concern...
Tensions used on girths on thoroughbred racehorses. To determine commonly used girth tensions in Thoroughbred racehorses in the Melbourne metropolitan area. Methods: A prospective industry survey. Methods: Strappers were instructed to tension girths, using the same saddle, under-saddle packing and girth, sufficiently to hold the saddle for racing. These tensions were continuously recorded by an in-line load cell in the girth. Seventeen strappers from five stables participated in the study, which was conducted on 91 horses. Results: Resting girth tensions varied considerably. The mean tension on inhalation was 13 +/- 0.4 kg. Male strappers recor...
Effects of exercise intensity and duration on plasma beta-endorphin concentrations in horses. To determine the relationship between plasma beta-endorphin (EN) concentrations and exercise intensity and duration in horses. Methods: 8 mares with a mean age of 6 years (range, 3 to 13 years) and mean body weight of 450 kg. Methods: Horses were exercised for 20 minutes at 60% of maximal oxygen consumption (VO2max) and to fatigue at 95% V02max. Plasma EN concentrations were determined before exercise, after a 10-minute warmup period, after 5, 10, 15, and 20 minutes at 60% VO2max or at the point of fatigue (95% VO2max), and at regular intervals after exercise. Glucose concentrations were deter...
The effect of high intensity exercise on the functional capacity of equine pulmonary alveolar macrophages and BAL-derived lymphocytes. The effect of strenuous exercise on the functional capacity of pulmonary alveolar macrophages (PAM) and bronchoalveolar lavage-derived lymphocytes was determined in eight horses prior to and after 7 weeks of training. Strenuous exercise had no effect on the total cell count or the percentage of live cells in bronchoalveolar lavage (BAL) samples prior to or following training. However, training was associated with a significant increase in the total cell count of pre-exercise BAL samples and a significant reduction in the percentage of live cells in post-exercise samples. Strenuous exercise was...
Carbohydrate supplementation of horses during endurance exercise: comparison of fructose and glucose. To delay the onset of fatigue, endurance horses are often fed at rest stops during races. The resulting increase in blood insulin may adversely inhibit lipolysis. In humans, ingestion of fructose produces a smaller insulin rise than glucose. This study compared glucose and fructose as carbohydrate supplements for endurance horses. Three Arabian geldings were given 300 g of fructose (F), glucose (G) or 50% glucose: 50% fructose (GF), in 1.5 L water, by stomach tube. In the Resting Test, carbohydrate was administered at rest. Following treatment, blood samples were taken every 30 min for 8 h, an...
Preferred speed and cost of transport: the effect of incline. Preferred speed is the behavioral tendency of animals to utilize a relatively narrow set of speeds near the middle of a much broader range that they are capable of using within a particular gait. Possible explanations for this behavior include minimizing musculoskeletal stresses and maximizing energetic economy. If preferred speed is determined by energetic economy (cost of transport, C(T)), then shifts in preferred speed should produce shifts in C(T). To test this hypothesis, preferred speeds were measured in trotting horses on the level and on an incline. The preferred trotting speed decreas...
Exercise alters fractal dimension and spatial correlation of pulmonary blood flow in the horse. We determined the changes in fractal dimensions and spatial correlations of regional pulmonary blood flow with increasing exercise in race horses (n = 4) by using 15-microm fluorescent microspheres. Fluorescence was measured to quantitate regional blood to 1.3-cm(3) samples (n = 1,621-2,503). Perfusion distributions were characterized with fractal dimensions (a measure of spatial variability) and spatial correlations. On average, the fractal dimension decreased with exercise (trot 1.216 to gallop 1.173; P < 0. 05) despite a variable fractal dimension at rest. Spatial correlation of flow to ...
Effects of warm-up intensity on kinetics of oxygen consumption and carbon dioxide production during high-intensity exercise in horses. To compare effects of low and high intensity warm-up exercise on oxygen consumption (VO2) and carbon dioxide production (VCO2) in horses. Methods: 6 moderately conditioned adult Standard-breds. Methods: Horses ran for 2 minutes at 115% of maximum oxygen consumption (VO2max), 5 minutes after each of the following periods: no warm-up (NoWU); 10 minutes at 50% of VO2max (LoWU); or 7 minutes at 50% VO2max followed by 45-second intervals at 80, 90, and 100% VO2max (HiWU). Oxygen consumption and VCO2 were measured during exercise, and kinetics of VO2 and VCO2 were calculated. Accumulated O2 deficit ...
Gait and speed as exercise components of risk factors associated with onset of fatigue injury of the third metacarpal bone in 2-year-old Thoroughbred racehorses. To determine the degree to which components of the training program of 2-year-old Thoroughbred racehorses influence their susceptibility to fatigue injury of the third metacarpal bone (bucked shins). Methods: 226 two-year-old Thoroughbred racehorses. Methods: Daily training information and health reports on 2-year-old Thoroughbreds were compiled from records provided from 5 commercial stables. For each horse, data (exercise variables) were collected that comprised distance jogged (approx speed of 5 m/s), galloped (approx 11 m/s), and breezed (approx 15 to 16 m/s) until a single instance of buc...
Effect of age and training on murmurs of atrioventricular valvular regurgitation in young thoroughbreds. Cardiac auscultation was carried out on 111 Thoroughbred horses age 2-5 years to test the hypothesis that athletic training might influence the development of atrioventricular (AV) valve regurgitation in young Thoroughbreds. Murmurs of valvular regurgitation were identified and graded on a 1-6 scale. There were 2 sources of auscultation data: 1) 55 2-year-old horses that were examined by auscultation before training commenced and 9 months later when at race fitness; 2) 56 horses age 2-5 years that were examined on one occasion only (25 2-year-olds, 23 3-year-olds, five 4-year-olds and five 5-y...
Comparison of three methods for estimation of exercise-related ion losses in sweat of horses. To quantify total fluid loss in sweat of Thoroughbreds during >3 hours of low-intensity exercise in controlled conditions and to calculate and compare estimated ion losses in sweat, according to 3 methods. Methods: 6 exercise-trained Thoroughbreds. Methods: Fluid and ion losses in sweat were measured in 6 horses exercising at 40% of the speed that elicited maximum oxygen consumption for 45 km. Horses were given a 15-minute rest period at the end of three 15-km exercise phases. Horses completed 2 exercise trials. Ion losses in sweat were calculated, using measurements of local sweating rate and...
Blood lactate responses to submaximal field exercise tests in thoroughbred horses. The associations between velocity during a standardized, submaximal 800-m exercise test and blood lactate concentration after exercise were investigated in Thoroughbred racehorses on sand and grass racetracks. Predicted lactate concentrations for each horse's exercise test velocity were calculated from the line of best fit derived from results at each racetrack. The repeatability of the differences between the measured and predicted blood lactate response to exercise was also investigated. Exercise tests were conducted at speeds ranging from 12.8 to 16.6 m/s. The variability of velocity within...
Association of high-speed exercise with racing injury in thoroughbreds. To determine the association between high-speed exercise and risk of injury while racing among Thoroughbreds in Kentucky. Methods: Matched case-control study. Methods: 206 Thoroughbreds that sustained a musculoskeletal injury while racing and 412 Thoroughbreds that were not injured during the same races. Methods: Data regarding official timed workouts and races and the Beyer's numbers for the 3 races before the race during which injury occurred were extracted from past performance charts and compared between injured horses and control horses. Results: For injured horses, cumulative distance of...
Jockey injuries in the United States. In the sport of horse racing, the position of the jockey and speed of the horse predispose the jockey to risk of injury. Objective: To estimate rates of medically treated injuries among professional jockeys and identify patterns of injury events. Methods: Cross-sectional survey from data compiled by an insurance broker. Information on the cause of injury, location on the track, and body part injured was evaluated. Methods: Official races at US professional racing facilities (n = 114) from January 1, 1993, through December 31, 1996. Methods: A licensed jockey population of approximately 2700 pe...