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.
Influence of girth strap tensions on athletic performance of racehorses. Eight horses were exercised at speeds to produce 80% of maximal heart rates, on 4 occasions using a randomised block design, and girthed at tensions of approximately 5, 10, 15 or 20 kg using a standard canvas girth attached to a racing saddle. Tension was recorded continuously using an in-line load cell connected to a physiograph. Horses ran until fatigued on a treadmill inclined at 10% slope. Tensions were measured at peak inhalation (T/inh) and exhalation (T/exh), recorded at rest (rest) and during exercise (ex). Data were analysed by ANOVA and, in addition, least squares linear regression w...
Fragility of red cells during exercise is affected by blood pH and temperature. We examined the relationship in horses between osmotic fragility of erythrocytes (OFE) measured as the red cell haemolysis rates (HLR) in 0.56% NaCl and certain physiological characters. Animals were exercised on a treadmill: warmed up at 30% VO2max for 5 min or at 105% VO2max for 1 min, given an exercise test at 80 or 105% VO2max until fatigued, and then cooled down. The pH and temperature of the blood had a significant correlation for the HLR: r = 0.93 and 0.92 (P < 0.01) on arterial and mixed venous blood, respectively. In multiple regression analysis, heart rate and packed cell volume s...
The effect of training on the calcified zone of equine middle carpal articular cartilage. Carpal osteochondral injury is frequently observed in strenuously trained horses. It is clear that the integrity of articular cartilage and subchondral bone are intimately related, although there is controversy about which component is the most important. Calcified cartilage provides the mechanical link between soft hyaline cartilage and stiff subchondral bone so it is essential to understand the tissue's response to exercise. Middle carpal calcified and uncalcified (hyaline) cartilage thickness was investigated in horses undergoing high- and low-intensity exercise. Twelve untrained horses (18...
Temporal changes in the trot between the first and third horse inspections at a CCI*** 3-day event. Kinematic parameters were measured from horses competing in a CCI*** 3-day event. The horses were filmed during the first and third horse inspection. This provided a repeat sample on 16 horses. The horses were filmed using a panning lateral S-VHS video camera (50 Hz). Spatial measurements were taken for mean +/- s.d. 5.66 +/- 0.92 strides for the first inspection and 5.05 +/- 1.27 for the third inspection. Within the calibration zone, data of the horses accelerating and obtaining a constant velocity were collected. The horses trotted with a higher mean velocity during the third inspection (0.2...
Effects of phlebotomy and autologous blood transfusion on oxygen transport in the racehorse. Because the haemoglobin concentration Hb[ during exercise may be at the upper limit of blood viscosity for effective oxygen delivery, we hypothesised that administration of blood would not further enhance oxygen delivery or exercise capacity. Six Thoroughbred geldings were used in 5 incremental treadmill exercise tests over a period of 4 weeks. The first test was performed 6 days prior to phlebotomy, which involved the removal of 20 ml/kg bwt of venous blood. Exercise tests were performed at 1, 8 and 15 days after blood removal. Six days after the 15 day post phlebotomy exercise test, blood fr...
Racing performance in red blood cell hypervolaemic standardbred trotters. The association between red blood cell hypervolaemia (RCHV) and racing performance was examined in 116 Standardbred trotters referred to the clinic during a 5 year period with histories of impaired racing performance. Red cell hypervolaemia was the only significant abnormality detected in a thorough clinical examination, cell volumes ranging 116-178% of the predicted normal values. They were also compared with the performance traits of the contemporary Swedish Standardbred trotter population (n = 58,058). The performance traits were based on earnings per year and start, best annual racing time...
Influence of rough track surfaces on components of vertical forces in cantering thoroughbred horses. No kinetic data are available to indicate the influence of a rough track surface and the resultant loss of footing on the components of hoof vertical forces. The aim of the present study was to evaluate the influence of rough track surfaces on the components of hoof vertical forces. Seven clinically sound 2-year-old Thoroughbred horses had instrumented shoes attached to both of the fore hooves to obtain the magnitudes of consecutive forces exerted in the hoof. All horses were cantered at approximately 10 m/s on straight tracks of smooth and rough surfaces of woodchip and dirt. The instrumented...
Thermoregulatory strategies during short-term exercise at different intensities. Previously we have observed a decline in sweating rate (SR) during high intensity exercise in an incremental test protocol. In man, the sweating sensitivity (SR/degree C) has been shown to vary with exercise intensity. The aim of the present study was to determine if thermoregulatory responses in the horse, a prolific sweater with a high rate of metabolic heat production, were modified by exercise intensity. The effect of 3 separate exercise intensities (50 (S), 70 (M) and 90% (F) VO2peak on neck (SRN) and gluteal sweating rate (SRG), pulmonary artery (TPA), rectal (TREC) and skin temperatures...
Comparison of some responses to exercise on the track and the treadmill in French trotters: determination of the optimal treadmill incline. The purpose of this study was to determine the optimal treadmill slope for trotters to produce the same heart rate and blood lactate responses as on the track during a standardized exercise test. Nine 2-year-old French trotters performed exercise tests on a training track and on a treadmill set at an incline of 0, 2 or 4%. For all horses, track testing was performed on day 1 and then on the treadmill according to a Latin-square design. The track test utilized three steps each of 3 min at speeds of 470, 530, 590 m/min and the same speeds were used on the treadmill. Derived physiological variabl...
Time of contact and step length: the effect of limb length, running speed, load carrying and incline. Using published values for twelve species of birds and mammals, we investigated the effects of limb length and running speed on time of contact and step length. In addition, we measured the time of contact in horses trotting up a 10 % incline and when carrying a load averaging 19 % of their body mass. From these values, we calculated stride period and step length. Our analysis of the interspecific data yielded the following relationship between time of contact (t(c) in s) and leg length (L in m) and running speed (v in m s(-)(1)): t(c)=0.80L(0.84)/v(0.87) (r(2)=0.97). Both exponents in this re...
Outcome and racing performance after internal fixation of third and central tarsal bone slab fractures in horses. A review of 20 cases. Twenty horses with central and third tarsal bone slab fractures, were treated internal fixation. Eighteen of the 20 cases were Standardbred trotters, one was a Thoroughbred racehorse and one a Swedish Warmblood. The central tarsal bone (CT) was involved in 12 cases and the third tarsal bone (T3) in 8 cases. The fractures were treated by lag screw fixation with one (18 cases) or two (2 cases) 3.5 or 4.5 mm cortical screws. Horses were confined to stall rest for one month and then put on a gradually increasing exercise programme. Convalescence time was 3-8 months until the fracture had healed an...
Monitoring training success using a lactate-speed relationship. Monitoring training by measuring blood lactate content is a well-known procedure in sports physiology. Because of the difficulties in standardizing a test procedure in field studies, this method is fraught with considerable problems when applying it to race horses. The aim of the present study was to develop a test procedure which is able to give evidence about the training state of different race horses after nonidentical test-loads. Under almost identical environmental conditions, the level of blood lactate was determined in five trotters which were kept in training. Immediately after the si...
Tenoscopic examination and proximal annular ligament desmotomy for treatment of equine “complex” digital sheath tenosynovitis. To determine the outcome of horses with "complex" digital tenosynovitis treated by tenoscopic proximal annular ligament desmotomy and resection of synovial masses or adhesions, or both, within the digital sheath. Methods: Retrospective evaluation. Methods: Twenty-five horses with a clinical and ultrasonographic diagnosis of palmar or plantar proximal annular ligament constriction and ultrasonographic evidence of synovial masses or adhesions within the digital tendon sheath. Methods: Each horse had tenoscopic surgery for annular ligament desmotomy combined with adhesiolysis and/or synovial mass...
Equine sweating responses to submaximal exercise during 21 days of heat acclimation. This study examined sweating responses in six exercise-trained horses during 21 consecutive days (4 h/day) of exposure to, and daily exercise in, hot humid conditions (32-34 degrees C, 80-85% relative humidity). On days 0, 3, 7, 14, and 21, horses completed a standardized exercise test on a treadmill (6 degrees incline) at a speed eliciting 50% of maximal O(2) uptake until a pulmonary artery temperature of 41.5 degrees C was attained. Sweat was collected at rest, every 5 min during exercise, and during 1 h of standing recovery for measurement of ion composition (Na(+), K(+), and Cl(-)) and swe...
Effects of prior exercise on muscle metabolism during sprint exercise in horses. The effect of warm-up exercise on energy metabolism and muscle glycogenolysis during sprint exercise (Spr) was examined in six fit Standardbred horses exercised at 115% of maximal O(2) consumption (VO(2 max)) until fatigued, 5 min after each of three protocols: 1) no warm-up (NWU); 2) 10 min at 50% of VO(2 max) [low-intensity warm-up (LWU)]; and 3) 7 min at 50% VO(2 max) followed by 45-s intervals at 80, 90, and 100% VO(2 max) [high-intensity warm-up (HWU)]. Warm-up increased (P < 0.0001) muscle temperature (T(m)) at the onset of Spr in LWU (38.3 +/- 0.2 degrees C) and HWU (40.0 +/- 0. 3 de...
Metabolic functions of L-carnitine and its effects as feed additive in horses. A review. L-carnitine, a betaine derivative of beta-hydroxybutyrate, is found in virtually all cells of higher animals and also in some microorganisms and plants. In animals it is synthesized almost exclusively in the liver. Two essential amino acids, i.e., lysine and methionine serve as primary substrates for its biosynthesis. Also required for its synthesis are sufficient amounts of vitamin B6, nicotinic acids, vitamin C and folate. The first discovered ergogenic function of L-carnitine is the transfer of activated long-chain fatty acids across the inner mitochondrial membrane into the mitochondrial m...
Injuries to polo riders: a prospective evaluation. To assess prospectively the incidence, nature, and severity of injuries to polo riders competing in the 1996 Argentine High Polo season. Methods: Assessment, documentation, and provision of care for all injuries sustained during the 1996 season by one of the authors. Riders were also surveyed retrospectively for their previous polo injuries. Results: 34 riders took part in the study. Nine injuries were sustained prospectively and 55 injuries were reviewed retrospectively (64 total). The injuries were categorised as minor (10), moderate (13), and major (41). Twenty five (39%) injuries occurred ...
Factors involved in the prognosis of equine laminitis in the UK. The significance of clinical and radiological parameters as prognostic indicators for laminitis, 'founder' and 'sinking syndrome' was studied using case records of 216 horses and ponies. Five animals were destroyed without treatment and were not included in the results of the study. One hundred and sixty-two (77%) animals returned to athletic soundness; 7 animals (3%) did not regain full athletic function, 42 animals (20%) died or were destroyed. Cases were assigned to 4 groups on the basis of initial clinical examination alone. These groups were laminitis, acute founder, 'sinker' and chronic ...
Cardiovascular demands of competition on low-goal (non-elite) polo ponies. Knowledge of the competitive demands of different sports or activities is important for designing appropriate training programmes to ensure that animals reach a sufficient level of fitness to reduce the risk of overexertion and injury or illness and to achieve the best possible performance in relation to an individual's genetic potential. Whilst the physiological demands of many equestrian sports have been described, to the best of our knowledge the cardiovascular demands of polo have not. The aims of the present study were therefore to record heart rate during and after competitive polo games...
Primary hypoparathyroidism in two horses. Two Thoroughbred horses were presented with various clinical signs which included sweating, agitation, muscle twitching and synchronous diaphragmatic flutter. These signs were associated with profound hypocalcaemia. A diagnosis of primary hypoparathyroidism was made on the basis of low serum ionised calcium concentration, hyperphosphataemia and markedly reduced serum immunoreactive parathyroid hormone concentrations in the presence of normal renal function. Treatment with a combination of intravenous calcium and subsequently oral calcium, magnesium and a vitamin D analogue (dihydrotachysterol)...
Limb locomotion–speed distribution analysis as a new method for stance phase detection. The stance phase is used for the determination of many parameters in motion analysis. In this technical note the authors present a new kinematical method for determination of stance phase. From the high-speed video data, the speed distribution of the horizontal motion of the distal limb is calculated. The speed with the maximum occurrence within the motion cycle defines the stance phase, and this speed is used as threshold for beginning and end of the stance phase. In seven horses the results obtained with the presented method were compared to synchronous stance phase determination using a for...
Results of treatment of 145 fractures of the third metacarpal/metatarsal condyles in 135 horses (1986-1994). The objectives of this study were to correlate condylar fracture characteristics and type of treatment with subsequent capacity for athletic ability, and to determine the characteristics of healing that affect prognosis after fracture fixation. Medical records, post operative radiographic studies and race records were examined for 135 horses sustaining 145 fractures. Sixty-five percent of horses overall started in a race post injury (SPI) in a mean time of 9.7 months with a mean of 13.7 races post injury. Having raced pre-injury did not confer an advantage to starting post injury, though nonst...
Use of electrocautery probes in arthroscopic removal of apical sesamoid fracture fragments in 18 Standardbred horses. To develop a technique for arthroscopic excision of apical sesamoid fracture fragments using electrocautery probes. Methods: A total of 18 Standardbred horses. Methods: Arthroscopic removal of apical sesamoid fracture fragments using both hook and loop electrocautery probes was performed on 18 Standardbred horses. The fracture fragments were approached using either an ipsilateral (3) or contralateral (15) arthroscopic triangulation technique. Distension of the metacarpo- (metatarso)-phalangeal joints was achieved using a 1.5% glycine solution. Under arthroscopic guidance, both the suspensory a...
A comparison of the ultrastructure and metabolic response of the skeletal muscle of horses performing intense treadmill exercise at 20 and 35 degrees C. The aim of this study was to determine whether the metabolic response and ultrastructure of muscle differed when horses performed intense exercise at different ambient temperatures. Four Standardbred geldings performed treadmill exercise, including an intensive trot of 2600 m on two different occasions, either at a high ambient temperature of 35 degrees C or at a temperature of 20 degrees C. The horses had a warm-up period of 23.5 min of submaximal exercise, followed by 2 h of box rest before the intensive exercise. Muscle biopsy data of adenine nucleotides, creatine phosphate, lactate and gly...
Anesthesia of horses with a combination of detomidine, zolazepam, tiletamine, and isoflurane immediately after strenuous treadmill exercise. To evaluate effects of strenuous exercise in adult horses immediately before anesthesia and to determine whether prior exercise affects anesthesia induction, recovery, or both. Methods: 6 healthy Thoroughbreds in good condition and trained to run on a treadmill, each horse serving as its own control. Methods: Horses ran on a treadmill until fatigued, then were sedated immediately with detomidine hydrochloride and anesthetized with a zolazepam hydrochloride-tiletamine combination. Anesthesia was maintained with isoflurane in oxygen for another 90 minutes. Blood samples were taken before, during...
Apical fracture of the proximal sesamoid bone in standardbred horses: 43 cases (1990-1996). To determine whether fracture fragment dimensions, suspensory ligament damage, and racing status at the time of injury were associated with outcome in Standardbred horses with apical fracture of the proximal sesamoid bone. Methods: Retrospective study. Methods: 43 Standardbred racehorses. Methods: Medical records, racing records, and radiographs were reviewed, and ultrasonographic findings were scored. Measurements of the fractured portion of the proximal sesamoid bone were made. Results: Seventy-four percent (32/43) of horses were pacers, and 26% (11/43) were trotters. Statistical differences...
Ablation of the nephrosplenic space for treatment of recurring left dorsal displacement of the large colon in a racehorse. Left dorsal displacement of the large colon was diagnosed in a 3-year-old Thoroughbred gelding. Conservative treatment that included lunging after administration of phenylephrine and rolling while under general anesthesia was not successful. The displaced segment of colon was reduced surgically through a ventral midline incision, but displacement recurred 4 days after surgery. Ablation of the nephrosplenic space by suturing the nephrosplenic ligament to the splenic capsule was performed through the left flank. At followup 1 year after surgery, the horse had not had further signs of colic and h...
Effects of feeding frequency and voluntary salt intake on fluid and electrolyte regulation in athletic horses. The effect of feeding frequency and voluntary sodium intake (VSI) on fluid shifts and plasma aldosterone concentration (PAC) were studied at rest and after exercise in six athletic horses. The horses were fed twice a day (2TD) and six times a day (6TD) for 25 days for each protocol, according to a changeover design. VSI was measured by weighing each horse's salt block daily. Feeding 2TD or 6TD caused no major alterations in fluid shifts, but in the 2TD treatment there was a postprandial increase in plasma protein concentration and osmolality that lasted <1 h. PAC and VSI were not affected b...
The influence of betaine on untrained and trained horses exercising to fatigue. Because exercise fatigue has been associated with the accumulation of lactic acid, factors that influence lactate metabolism during exercise can potentially enhance performance. The objective of this study was to examine the effects of supplemental betaine on eight mature Thoroughbred horses before and after 8 wk of conditioning. The effects of betaine were tested in two cross-over design experiments, allowing each horse to receive both the control and betaine treatments at each fitness level. Ingestion of 80 mg of betaine/kg of BW for 14 d before exercise testing did not alter plasma lactate,...