Exercise in horses encompasses the physical activities that horses engage in, either through natural behaviors or structured training programs. These activities impact a horse's musculoskeletal, cardiovascular, and respiratory systems, influencing overall health and performance. Exercise can vary in intensity, duration, and frequency, and its effects are studied to understand conditioning, endurance, and recovery processes in equines. Research in this field often focuses on the physiological adaptations to different types of exercise, the prevention of exercise-related injuries, and the optimization of training regimens for various equestrian disciplines. This page compiles peer-reviewed research studies and scholarly articles that explore the physiological, biomechanical, and health-related aspects of exercise in horses.
Mukai K, Ohmura H, Matsui A, Aida H, Takahashi T, Jones JH.We examined the effects of high-intensity training in normobaric hypoxia on aerobic capacity and exercise performance in horses and the individual response to normoxic and hypoxic training. Eight untrained horses were studied in a randomized, crossover design after training in hypoxia (HYP; 15.0% inspired O ) or normoxia (NOR; 20.9% inspired O ) 3 days/week for 4 weeks separated by a 4-month washout period. Before and after each training period, incremental treadmill exercise tests were performed in normoxia. Each training session consisted of 1 min cantering at 7 m/s and 2 min galloping ...
Takahashi Y, Ohmura H, Mukai K, Shiose T, Takahashi T.Horses need aggressive cooling to prevent exertional heat illness after strenuous exercise in hot and humid conditions. This study compared various methods for cooling horses in such conditions, testing the hypothesis that continual application of running water would be the most effective method to decrease core temperature. Five Thoroughbreds were exercised on a treadmill at wet-bulb globe temperature of 31.8 ± 0.1°C until their pulmonary artery temperature reached 42°C. The time until the pulmonary artery temperature returned to <39°C (t) and the rectal temperature at 30 minutes afte...
Mach N, Ruet A, Clark A, Bars-Cortina D, Ramayo-Caldas Y, Crisci E, Pennarun S, Dhorne-Pollet S, Foury A, Moisan MP, Lansade L.We simultaneously measured the fecal microbiota and multiple environmental and host-related variables in a cohort of 185 healthy horses reared in similar conditions during a period of eight months. The pattern of rare bacteria varied from host to host and was largely different between two time points. Among a suite of variables examined, equitation factors were highly associated with the gut microbiota variability, evoking a relationship between gut microbiota and high levels of physical and mental stressors. Behavioral indicators that pointed toward a compromised welfare state (e.g. stereotyp...
Ferlazzo A, Cravana C, Fazio E, Medica P.The review discusses the hormonal changes during exercise stress. The exercise generally produces a rise of adrenaline (A), noradrenaline (NA), adrenocorticotropic hormone (ACTH), cortisol, glucagon, growth hormone, arginine vasopressine, etc., and a drop of insulin. The hormonal events during reestablishment of homeostasis due to exercise stress can be divided into a catabolic phase, with decreased tolerance of effort, and reversible biochemical, hormonal and immunological changes, and an anabolic phase, with a higher adaptive capacity, and enhanced performance. The two main hormonal axes act...
Fintl C, Krontveit R, Risberg Å, Hanche-Olsen S, Slack J.The Norwegian-Swedish Coldblooded Trotter (NSCT) is an important breed in Norwegian and Swedish harness racing. In spite of this, little is known about its cardiac measurements and factors that may influence these. The aims of this study were to establish reference intervals (RI) for a series of conventional echocardiographic variables, primarily of the left heart, in NSCTs in race training and to evaluate any effects age, gender, estimated body weight (EBW), number of starts and racing performance may have on these. Methods: Sixty-three apparently healthy NSCTs in race training. Methods: Obse...
Fagan MM, Harris P, Adams A, Pazdro R, Krotky A, Call J, Duberstein KJ.Vitamin E is an essential antioxidant that may benefit athletes by reducing oxidative stress and influencing cytokine expression. Supplements can be derived from natural or manufactured synthetic sources. This study aimed to determine (1) if supplemental vitamin E is beneficial to exercising horses and (2) if there is a benefit of natural versus synthetic vitamin E. After 2 weeks on the control diet (vitamin E-deficient grain and hay), 18 horses were divided into three groups and fed the control diet plus (1) 1000 IU/d synthetic α-tocopherol (SYN-L), (2) 4000 IU/d synthetic α-tocopherol (SYN...
Dittmann MT, Latif SN, Hefti R, Hartnack S, Hungerbühler V, Weishaupt MA.The use of horses in competitive sports receives increasing criticism from the public, mainly due to the potential for injury. However, it is unclear if orthopedic and other health issues are more common in competition horses than those in leisure horses. The aim of this study was to assess husbandry, use, and orthopedic health in Swiss riding horses and to compare these aspects between horses owned by self-identified competitive riders (CR) and leisure riders (LR) in Switzerland. A total of 237 owners completed an online survey providing information on their athletic ambitions, their horse's ...
Carvalho Filho WP, Girardi FM, Souto PC, Orozco AMO, de Oliveira T, Dornelas LRSM, Jimenez AKA, Fonseca LAD.The objective of this study was to evaluate the serum proteinogram, identifying and quantifying the acute-phase proteins (APPs) of horses used in show jumping activity with obstacles of a meter in height. As it is an equestrian sport that involves high intensity and excessive impact, the possibility of injury is relevant. The serum of 10 horses was evaluated in a competition for beginners. The material was collected at rest (T0), immediately after exercise (T1), 30 minutes after the effort (T2), 1 hour after the effort (T3), and 24 hours after the effort. Acute-phase proteins were separated...
Ellis KL, King MR.Postural stability maintains balance, protects the spinal column, and allows accurate responses to destabilizing forces. The musculus multifidus (m. multifidus) is the major postural muscle located adjacent to the vertebrae along the length of the spinal column. Increased cross-sectional area (CSA) of the m. multifidus has been demonstrated in horses after a rehabilitation strengthening exercise program; however, correlation with functional postural stability has not been shown. The objective of the present study is to evaluate the relationship of the thoracolumbar m. multifidus CSA and measur...
Munsters CCBM, Kingma BRM, van den Broek J, Sloet van Oldruitenborgh-Oosterbaan MM.In human sport science, the acute:chronic workload (ACWR) ratio is used to monitor an athlete's preparedness for competition and to assess injury risks. The aim of this study was to investigate whether acute and chronic workload calculations for external and internal loads (e.g. high-speed work distance and associated exertional effort) were associated with injury risk in elite eventing horses and to identify workloads performed by horses competing in different competition and at different fitness levels. Training load and injury data were collected from 58 international eventing horses (CCI2*...
Knych HK, Arthur RM, McKemie DS, Baden RW, Seminoff K, Kass PH.Flunixin meglumine (FM) and phenylbutazone (PBZ) are potent anti-inflammatory agents and as such their potential to mask injuries that would otherwise keep a horse from training or racing is concerning. A common practice in racetrack medicine in the USA is to administer the two drugs within close proximity (24 hours apart) of each other, raising the concern of pharmacokinetic interactions and enhanced anti-inflammatory effects. Objective: Describe the pharmacokinetics and effects of PBZ on the clearance of FM when administered in close proximity as well as effects on inflammatory mediators. M...
Katz LM, Stallard J, Holtby A, Hill EW, Allen K, Sweeney J.Although inspiratory muscle training (IMT) is reported to improve inspiratory muscle strength in humans little has been reported for horses. We tested the hypothesis that IMT would maintain and/or improve inspiratory muscle strength variables measured in Thoroughbreds during detraining. Thoroughbreds from one training yard were placed into a control (Con, n = 3 males n = 7 females; median age 2.2±0.4 years) or treatment group (Tr, n = 5 males, n = 5 females; median age 2.1±0.3 years) as they entered a detraining period at the end of the racing/training season. The Tr group underwent eight we...
Cappelli K, Mecocci S, Gioiosa S, Giontella A, Silvestrelli M, Cherchi R, Valentini A, Chillemi G, Capomaccio S.Physical exercise is universally recognized as stressful. Among the "sport species", the horse is probably the most appropriate model for investigating the genomic response to stress due to the homogeneity of its genetic background. The aim of this work is to dissect the whole transcription modulation in Peripheral Blood Mononuclear Cells (PBMCs) after exercise with a time course framework focusing on unexplored regions related to introns and intergenic portions. PBMCs NGS from five 3 year old Sardinian Anglo-Arab racehorses collected at rest and after a 2000 m race was performed. Apart from d...
Shono S, Gin A, Minowa F, Okubo K, Mochizuki M.Diacron-reactive oxygen metabolite (d-ROM) and biological antioxidant potential (BAP) levels in the serum of horses were measured (ponies, = 15; thoroughbred, = 31; other full-sized horses, = 7). The mean d-ROM levels in horses were significantly higher ( < 0.001) than those in dairy cattle ( = 25) and dogs ( = 31). However, d-ROM levels in horses were lower than the standard levels reported in humans. When d-ROM and BAP levels were plotted graphically, the points for horses with a disease (ringbone in 1 Japanese sports horse, cellulitis in 1 thoroughbred, melanoma in 1 Lipizzaner) fell ...
Ebert M, Moore-Colyer MJS.The aim of this study was to estimate the energy requirements of performance horses in active, variable training in the field. Sixty horses in England and Switzerland were measured over 2-wk periods and, for 15 of these, the measurement period was extended, ranging from 21 to 42 wk. Energy intake was estimated by measuring daily feed consumption. Energy output was measured using heart rate (HR) monitors during 608 training sessions, relating HR to volume of oxygen (VO₂) and converting VO₂ to energy. Field maintenance requirements were calculated by deducting the marginal energy cost of tra...
Szemplinski KL, Thompson A, Cherry N, Guay K, Smith WB, Brady J, Jones T.The objective of this study was to determine if transportation and exercise stress in horses affect the microflora populations in the equine hindgut. Four horses were subjected to three transport periods (0, 3, and 6 hours) with a 7-d rest period between each transport. Horses were fed 0.91 kg/day of Purina Impact All Stages 12% and had ad libitum access to Cynodon dactylon (Coastal Bermudagrass) hay. Fecal samples were collected before (0 hours) and after (48 hours) transport. In addition, three horses underwent a different standardized exercise test with a 7-d rest period between each ex...
Arfuso F, Giannetto C, Fazio F, Panzera F, Piccione G.Physiological and hematochemical changes associated with exercise have been extensively investigated in equine species. It is known that stress elevates circulating levels of acute phase proteins (APPs). This survey evaluated whether horses trained with different training programs exhibit changes in APP levels after exercise event. Twenty Saddle Italian horses (11 geldings and 9 females, 9 ± 1 years old, body weight of 425 ± 35 kg) were divided into two equal groups according to the intensity of training programs they were subjected: group A was subjected to an intense training program, gr...
Kiely M, Warrington G, McGoldrick A, Cullen S.Kiely, M, Warrington, G, McGoldrick, A, and Cullen, S. Physical preparation strategies of professional jockeys. J Strength Cond Res 36(11): 3184-3189, 2022-Professional horse racing is a physically demanding sport. The aim of the study was to examine the physical preparation strategies of jockeys for racing. A questionnaire was developed and validated which comprised of 4 sections; (a) background information, (b) making weight and current associated exercise habits, (c) current physical activity practices, and (d) jockey perceptions of strength and conditioning (S&C) and current practices....
Bruschetta G, D'Ascola A, Medica P, Ferlazzo AM.Serotonin (5-hydroxytryptamine [5-HT]) may induce metabolic effects in different cell types, including leukocytes. In horses, 5-HT is involved in physiological and behavioral functions. Physical exercise is known to increase the amounts of 5-HT both in brain and periphery, but so far, the signal mechanism in response to exercise is not known. The aim of the study was to investigate the effect of a racehorse intensive training session on plasma 5-HT levels, serotonin transporter (SERT), 5HT, 5-HT, 5-HT, 5-HT receptor, interleukin-1 beta, and tumor necrosis factor-alpha expression in horse perip...
Hardeman AM, Byström A, Roepstorff L, Swagemakers JH, van Weeren PR, Serra Bragança FM.Clinical assessment of spinal motion in horses is part of many routine clinical exams but remains highly subjective. A prerequisite for the quantification of spinal motion is the assessment of the expected normal range of motion and variability of back kinematics. The aim of this study was to objectively quantify spinal kinematics and between -measurement, -surface and -day variation in owner-sound horses. In an observational study, twelve owner-sound horses were trotted 12 times on four different paths (hard/soft straight line, soft lunge left and right). Measurements were divided over three ...
Wilk I, Wnuk-Pawlak E, Janczarek I, Kaczmarek B, Dybczyńska M, Przetacznik M.It was assumed that a horse with its rider body weight found in the upper limit may negatively impact the horse's welfare. The objective of this paper was to analyze the differences in body temperature and selected heart rate parameters in horses in response to physical exercise accompanied by various rider's body weight loads. The study was carried out on 12 leisure, 10-15-year-old warmblood geldings. The horses were ridden by two equally qualified riders whose body weights were about 20% and 10% of the average body weight (BW) of the animals (about 470 kg). Each rider rode each of the 12 hor...
Kim DH, Lee HG, Sp N, Kang DY, Jang KJ, Lee HK, Cho BW, Yang YM.To understand the athletic characteristics of Thoroughbreds, high-throughput analysis has been conducted using horse muscle tissue. However, an in vitro system has been lacking for studying and validating genes from in silico data. The aim of this study is to validate genes from differentially expressed genes (DEGs) of our previous RNA-sequencing data in vitro. Also, we investigated the effects of exercise-induced stress including heat, oxidative, hypoxic and cortisol stress on horse skeletal muscle derived cells with the top six upregulated genes of DEGs. Enriched pathway analysis was conduct...
Allen KJ, Fitzharris LE, McConnell AK.Inspiratory muscle training applies a training stimulus directly to the inspiratory muscles and is distinct from whole-body training. The potential benefits of inspiratory muscle training have yet to be explored in horses. Objective: The objectives were as follows: (a) to develop an equine-specific method of testing and training inspiratory muscles; (b) to assess tolerance and feasibility in a pilot study in a commercial Thoroughbred training establishment. Methods: Field study. Methods: A mask was used to interface commercial human inspiratory muscle training equipment. Ten horses undertook i...
Kau S, Potz IK, Pospisil K, Sellke L, Schramel JP, Peham C.Bit configuration and acting rein forces play a crucial role in oral health and comfort of ridden horses. Although it is a big animal welfare issue, dynamic response of horses to different bits has yet not been thoroughly investigated. This convenience sample experimental study describes a model to overcome the almost uncontrollable influence of riders on rein tension and evaluates self-controlled maximum side rein tension of ten sound horses randomly bitted with a double-jointed (DJS) and a version of a Mullen mouth snaffle-bit under unridden conditions. Horses were exercised at walk and trot...
Santschi EM, Whitman JL, Prichard MA, Lopes MAF, Pigott JH, Brokken MT, Jenson PW, Johnson CR, Morrow C, Brusie RW, Juzwiak JS, Morehead JP.To describe subchondral lucencies (SCL) in the equine proximal tibia, several treatment options, and clinical outcomes. Methods: Retrospective study. Methods: Seventeen horses with proximal tibial SCL. Methods: Medical record and radiograph review. Follow-up was obtained via examination and radiography when possible and by telephone and race records when required. The median duration of follow-up was 20 months (range, 0-48). Results: Proximal tibial SCL were associated with lameness in 14 of 17 horses. Subchondral lucencies were primary in 11 horses and secondary to an ipsilateral medial fem...
Saitua A, Becero M, Argüelles D, Castejón-Riber C, Sánchez de Medina A, Satué K, Muñoz A.Horse trainers often claim that exercise on a water treadmill (WT) leads to a greater muscle power and development compared to terrestrial locomotion, because of the greater viscosity of water compared to air. This research assesses locomotor changes measured with accelerometers fixed in the pectoral region and in the sacrum midline in six horses subjected to exercise sessions of 40 min duration on a WT without water (DT), and with water at the depth of fetlock (FET) and carpus (CAR) with velocities of 6 km/h and at the depth of stifle (STF) at 5 km/h. Another five horses performed the same ex...
Paine SW, Bright J, Scarth JP, Hincks PR, Pearce CM, Hannan C, Machnik M, Hillyer L.In equine and racing practice, detomidine and butorphanol are commonly used in combination for their sedative properties. The aim of the study was to produce detection times to better inform European veterinary surgeons, so that both drugs can be used appropriately under regulatory rules. Three independent groups of 7, 8 and 6 horses, respectively, were given either a single intravenous administration of butorphanol (100 µg/kg), a single intravenous administration of detomidine (10 µg/kg) or a combination of both at 25 (butorphanol) and 10 (detomidine) µg/kg. Plasma and urine concentratio...
Garber A, Hastie P, Murray JA.Gastrointestinal microbiota play a crucial role in nutrient digestion, maintaining animal health and welfare. Various factors may affect microbial balance often leading to disturbances that may result in debilitating conditions such as colic and laminitis. The invention of next-generation sequencing technologies and bioinformatics has provided valuable information on the effects of factors influencing equine gut microbiota. Among those factors are nutrition and management (e.g., diet, supplements, exercise), medical substances (e.g., antimicrobials, anthelmintics, anesthetics), animal-related ...
Trindade PHE, Hartmann E, Keeling LJ, Andersen PH, Ferraz GC, Paranhos da Costa MJR.The horses' responses to exercise are commonly monitored using physiological variables, nonetheless physical and mental states can also be expressed through body language. The aims of this study were: (i) to identify how facial expressions and other behavioural variables change in ranch horses after a routine workday, and (ii) to investigate if these changes can be used as indicators of physical tiredness by relating them to known variables of physical fitness and workload. Fourteen crossbred ranch horses were assessed pre- and post-workday on two farms, recording the body language, physiologi...
Hellings IR, Krontveit R, Øverlie M, Kallmyr A, Holm T, Fintl C.Elevated cardiac troponin T (cTnT) concentrations may provide evidence of myocardial injury but physiological post-exercise release also occurs. Reference intervals are not fully established in horses making interpretation difficult. The aims of this study were to establish an upper reference limit for serum cTnT, compare pre-and post-race serum cTnT concentrations, and to evaluate factors that may influence these in a population of healthy, race-fit Standardbred racehorses. Serum samples were collected pre- (n = 108) and 1-2 h post-racing (n = 101) and analysed using a high sensitivity-cTnT a...
Wickler SJ, Greene HM, Egan K, Astudillo A, Dutto DJ, Hoyt DF.The relationship between fatigue and stride and/or muscle stiffness requires further study. Objective: To measure stride parameters in horses undergoing fatigue associated with running at submaximal speeds both on a treadmill and in an endurance ride. Objective: Stride frequencies and estimates of hindlimb stiffness would be decreased in fatigued horses. Methods: Horses were fatigued using 2 paradigms: run to exhaustion at a treadmill (4.5 m/sec, 6% incline) and finishing an 80 km endurance ride. Videos were digitised before and after fatigue and analysed for stride parameters: hind limb lengt...
Dixon PM, McGorum BC, Railton DI, Hawe C, Tremaine WH, Pickles K, McCann J.Examination of the long-term histories and clinical findings was performed in 351 horses suffering from recurrent laryngeal neuropathy (RLN) to examine for possible evidence of progression of this disorder. Fifty-two out of 351 cases (15%) had evidence of progression of the degree of laryngeal dysfunction over a median period of 12 months (range 1.5-48 months) with the onset of progression occurring at median age 7 years. In 30 cases, there was both endoscopic (median deterioration of 3 endoscopic grades; range 1-5 grades) and clinical evidence, with 29 (97%) of these horses concurrently devel...
Powis G, Snow DH.There are now several examples showing that experimentally induced changes in hepatic blood flow can have a marked effect upon the elimination of certain high clearance drugs. Changes in hepatic blood flow produced by exercise might therefore be expected to influence the clearance of these drugs. There was an increase of up to 100%, compound to control values, in the plasma levels of propranolol in horses given either d- or dl-propranolol, 0.2 mg/kg b.wt., and then subjected to sustained exercise for 30 minutes. There was, however, no similar increase with exercise in the plasma levels of anti...
Van Harreveld PD, Lillich JD, Kawcak CE, Gaughan EM, Mclaughlin RM, Debowes RM.To evaluate clinical effects of immobilization followed by remobilization and exercise on the metacarpophalangeal joint (MPJ) in horses. Methods: 5 healthy horses. Methods: After lameness, radiographic, and force plate examinations to determine musculoskeletal health, 1 forelimb of each horse was immobilized in a fiberglass cast for 7 weeks, followed by cast removal and increasing amounts of exercise, beginning with hand-walking and ending with treadmill exercise. Lameness examination, arthrocentesis of both MPJ, single-emulsion radiographic examination, nuclear scintigraphic examination, grou...
O'Connor CI, Lawrence LM, Lawrence AC, Janicki KM, Warren LK, Hayes S.Ten horses of Thoroughbred or Standardbred breeding were used to study the effects of dietary fish oil supplementation on the metabolic response to a high-intensity incremental exercise test. Horses were assigned to either a fish oil (n = 6) or corn oil (n = 4) treatment. The fish oil (Omega Protein, Hammond, LA) contained 10.6% eicosapentaenoic acid and 8% docosahexaenoic acid. Each horse received timothy hay and a textured concentrate at a rate necessary to meet its energy needs. The supplemental oil was top-dressed on the concentrate daily at a rate of 324 mg/kg BW. Horses received their as...
Gunther-Harrington CT, Arthur R, Estell K, Martinez Lopez B, Sinnott A, Ontiveros E, Varga A, Stern JA.Exercise induced cardiac fatigue (EICF) and cardiac dysrhythmias are well described conditions identified in high-level human athletes that increase in frequency with intensity and duration of exercise. Identification of these conditions requires an understanding of normal pre- and post-race cardiac assessment values. The objectives of this study were to (1) characterize selected indices of cardiac function, electrophysiologic parameters, and biochemical markers of heart dysfunction prior to and immediately after high level racing in Thoroughbred horses receiving furosemide; and (2) create pre...
Ropka-Molik K, Stefaniuk-Szmukier M, Piórkowska K, Szmatoła T, Bugno-Poniewierska M.Apoptosis plays an important role in the regulation of healthy tissue growth and development as well as in controlling the maintenance of homeostasis in exercising muscles. During an intensive physical effort, the regulation of cell death by apoptosis results in the replacement of unaccustomed muscle cells by new cells that are better suited to exercise. The aim of this study was to determine the expression of two genes (SH3FR1 and SH3RF2) that control apoptosis in muscle tissues during training periods characterized by different intensities. The gene expression levels were estimated using rea...
Martig S, Hitchens PL, Stevenson MA, Whitton RC.The repetitive large loads generated during high-speed training and racing commonly cause subchondral bone injuries in the metacarpal condyles of racehorses. Adaptive bone modelling leads to focal sclerosis at the site of highest loading in the palmar aspect of the metacarpal condyles. Information on whether and how adaptive modelling of subchondral bone changes during the career of a racehorse is sparse. The aim of this cross-sectional study was to describe the changes in subchondral bone micromorphology in the area of highest loading in the palmar aspect of the metacarpal condyle in thorough...
Nolazco Sassot L, Villarino NF, Dasgupta N, Morrison JJ, Bayly WM, Gang D, Sanz MG.A comprehensive study of the effect of supramaximal exercise in lipid homeostasis of Thoroughbreds provides the basis for future research on the role of lipids on energy metabolism in racehorses. Objective: To compare the plasma lipidome of Thoroughbreds before and after supramaximal exercise using an untargeted lipidomics approach. Methods: Pilot experimental study. Methods: Four Thoroughbred horses were used. The maximal oxygen consumption (VO ) was calculated for each horse. Horses then underwent treadmill exercise at the speed for which the oxygen requirements had been calculated to be 11...
White-Lewis S, Johnson R, Ye S, Russell C.To compare equine-assisted therapy to exercise education on pain, range of motion, and quality of life in adults and older adults with arthritis. Quality of life for adults and older adults is negatively impacted by arthritis pain, stiffness, and decreased function. Equine-assisted therapy provides unique movements to the rider's joints and muscles improving pain, range of motion, and quality of life and has improved outcomes in balance, gait, strength, functional mobility, and spasticity for older adults, stroke, spinal cord injury, and multiple sclerosis patients. No research has investigate...
Pedersen PJ, Karlsson M, Flethøj M, Trachsel DS, Kanters JK, Klaerke DA, Buhl R.Quantitative measurements of cardiac repolarization, defined as the electrocardiographic QT interval, have important diagnostic implications in humans, as irregularities can trigger potentially fatal ventricular tachyarrhythmia. In both humans and horses, cardiac repolarization is influenced to some extent by heart rate, age, body weight (BW), sex, autonomic tone, and environment. In horses, there is substantial inter-breed variation in size and training, and the aims of this study were therefore to determine the best model describing the QT to RR relationship in breeds of various athletic hor...
Brown MP, Trumble TN, Plaas AH, Sandy JD, Romano M, Hernandez J, Merritt KA.(1) To investigate the effects of exercise and osteochondral (OC) injury on synovial fluid (SF) chondroitin sulfate (CS) and hyaluronan (HA) concentration and chain length, (2) to compare SF and cartilage CS data from joints with OC fragmentation, and (3) to compare SF CS and HA profiles with those seen in serum from the same horses. Methods: Serum and SF were obtained from (1) normal horses after 8 weeks rest, (2) the same horses after 9 months treadmill training, and (3) horses with OC injury from racing. Articular cartilage was also collected from group 3 horses. Concentrations and chain le...
Moore JL, Siciliano PD, Pratt-Phillips SE.Weight loss plans in horses typically use dietary restriction, but exercise may have additional benefits. This study aimed to compare the effects of a diet or exercise protocol resulting in comparable caloric restriction in obese horses. Ten obese horses were paired according to sex, age, and breed or breed type. One horse from each pair was randomly assigned to either diet (DIET)-intake restricted to approximately 85% of digestible energy requirements or exercise (EX)-exercised to expend approximately 15% of digestible energy requirements, resulting in 85% of requirements available, for 4 we...
Bentley VA, Sample SJ, Livesey MA, Scollay MC, Radtke CL, Frank JD, Kalscheur VL, Muir P.Failure of functional adaptation to protect the skeleton from damage is common and is often associated with targeted remodeling of bone microdamage. Horses provide a suitable model for studying loading-related skeletal disease because horses are physically active, their exercise is usually regulated, and adaptive failure of various skeletal sites is common. We performed a histologic study of the navicular bone of three groups of horses: (1) young racing Thoroughbreds (n = 10); (2) young unshod ponies (n = 10); and (3) older horses with navicular syndrome (n = 6). Navicular syndrome is a painfu...
Williams JW, Pascoe JR, Meagher DM, Hornof WJ.Upper airway pressure was measured with a nasotracheal catheter system and a portable pressure transducer in 10 normal horses during maximal exercise before and after left recurrent laryngeal neurectomy. Measurements were repeated 16 weeks after prosthetic laryngoplasty (5 horses) or subtotal arytenoidectomy (5 horses). During maximal exertion, prosthetic laryngoplasty was more effective than subtotal arytenoidectomy in reversing the increases in upper airway pressure that followed left recurrent laryngeal neurectomy.
Stefánsdóttir GJ, Ragnarsson S, Gunnarsson V, Jansson A.This study examined the response in terms of heart rate (HR), respiratory rate (RR), haematocrit (Htc), rectal temperature (RT), and some plasma variables in Icelandic horses of different sexes and ages performing the riding assessment in a breed evaluation field test (BEFT). The study was conducted in Iceland on 266 horses (180 mares and 86 stallions, divided into four age groups; 4, 5, 6 and ≥7 years old). RT and RR were recorded and blood samples were taken before the warm-up and after the riding assessment. Horse HR, velocity and distance were recorded during the warm-up, the riding asse...
Holbrook TC, Birks EK, Sleeper MM, Durando M.Information is lacking regarding the influence of long distance exercise on the systemic concentration of cardiac troponin I (cTnI) in horses. Objective: To determine if the concentration of cTnI in horses competing in 80 and 160 km endurance races increases with exercise duration and if cTnI concentrations can be correlated with performance data. Methods: Blood samples for the measurement of cTnI and 3 min electrocardiogram recordings were obtained from horses prior to, during and after completion of 80 and 160 km endurance races at 3 ride sites during the 2004 and 2005 American Endurance Rid...
Tyler CM, Golland LC, Evans DL, Hodgson DR, Rose RJ.Thirteen standardbred horses were trained as follows: phase 1 (endurance training, 7 wk), phase 2 (high-intensity training, 9 wk), phase 3 (overload training, 18 wk), and phase 4 (detraining, 12 wk). In phase 3, the horses were divided into two groups: overload training (OLT) and control (C). The OLT group exercised at greater intensities, frequencies, and durations than group C. Overtraining occurred after 31 wk of training and was defined as a significant decrease in treadmill run time in response to a standardized exercise test. In the OLT group, there was a significant decrease in body wei...
Sleeper MM, Kearns CF, McKeever KH.Chronic administration of pharmacological levels of beta2-agonists have been shown to have toxic effects on the heart; however, no data exist on cardiac function after chronic clenbuterol administration. The purpose of this study was to examine the effect of therapeutic levels of clenbuterol on cardiac performance. Methods: Twenty unfit Standardbred mares were divided into four experimental groups: clenbuterol (2.4 microg.kg(-1) twice daily 5 d.wk(-1)) plus exercise (20 min at 50% .VO(2max)) (CLENEX; N = 6), clenbuterol (CLEN; N = 6), exercise (EX; N = 4), and control (CON; N = 4). M-mode and ...
Wilson G, Pritchard PP, Papageorgiou C, Phillips S, Kumar P, Langan-Evans C, Routledge H, Owens DJ, Morton JP, Close GL.The present study assessed the effects of a diet and exercise intervention in jockeys on body composition, metabolism, bone and mental health. 10 jockeys followed an individually prescribed 6-wk diet (Carbohydrate=2.5-3.5 g/kg, Protein=2.5 g/kg, Fat=1.0 g/kg). Body mass (59.2±4.6 vs. 57.6±4.5 kg), fat mass (7.5±3.5 vs. 6.2±2.6) and body fat (13.1±5.9 vs. 11.5±4.9%) all decreased (P<0.05) from pre to post-intervention whilst lean mass (47.1±5.3 vs. 47.0±5.5 kg) was maintained (P=0.80). RMR (1703±329 vs. 1975±313 kcal.d(-1)), VO2max (3.8±0.8 vs. 4.1±0.7 L/min(- 1))...
Cappelli K, Verini-Supplizi A, Capomaccio S, Silvestrelli M.The knowledge of molecular mechanisms of stress response in athlete horses can allow us to plan an appropriate and high-grade training to obtain better performance and to preserve horse welfare. It is well known that excessive muscular exercise can lead to a number of responses which may be associated with modification of the mRNA levels for a number of metabolic genes such as those involved in the immune response. In the present study cDNA-AFLP technique was applied to Arab endurance horses under stressing conditions to visualise variations of transcriptional profiles; 49 transcript derived f...
Noble P, Singer ER, Jeffery NS.Sagittal fractures of the first phalanx are a common, potentially catastrophic injury in racehorses. These fractures are often linked to an acute, one time, biomechanical event; however, recent evidence implies that chronic exposure to stress can lead to the accumulation of bony changes that affect the structural integrity of the bone and increase the likelihood of fracture. The aim of the study was to compare variations of two common metrics of bone adaptation - subchondral bone density and thickness across the proximal articular surface of the first phalanx in Thoroughbred horses that (1) ra...
Mukai K, Hiraga A, Eto D, Takahashi T, Hada T, Tsubone H, Jones JH.To determine whether warm-up exercise at different intensities alters kinetics and total contribution of aerobic power to total metabolic power in subsequent supramaximal exercise in horses. Methods: 11 horses. Methods: Horses ran at a sprint until fatigued at 115% of maximal oxygen consumption rate (VO(2max)), beginning at 10 minutes following each of 3 warm-up protocols: no warmup (NoWU), 1 minute at 70% VO(2max) (moderate-intensity warm-up [MoWU]), or 1 minute at 115% VO(2max) (high-intensity warm-up [HiWU]). Cardiopulmonary and blood gas variables were measured during exercise. Results: Th...
Sp N, Kang DY, Kim DH, Lee HG, Park YM, Kim IH, Lee HK, Cho BW, Jang KJ, Yang YM.Cortisol is a hormone involved in stress during exercise. The application of natural compounds is a new potential approach for controlling cortisol-induced stress. Tumour suppressor protein p53 is activated during cellular stress. Succinate dehydrogenase complex subunit A () and hypoxanthine phosphoribosyl transferase 1 () are considered to be two of the most stable reference genes when measuring stress during exercise in horses. In the present study cells were considered to be in a 'stressed state' if the levels of these stable genes and the highly stress responsive gene p53 were altered. It ...
Brama PA, Holopainen J, van Weeren PR, Firth EC, Helminen HJ, Hyttinen MM.There is ample evidence on topographical heterogeneity of the principal biochemical components of articular cartilage over the surface of the joint and the influence of loading thereon, but no information on depth-related zonal variation in horses. Objective: To study depth-related zonal variation in proteoglycan (PG) and collagen content in equine articular cartilage. Methods: Two techniques (safranin-O densitometry and Fourier transform infrared spectroscopy) were applied to sections of articular cartilage from the proximal phalangeal bone of the metacarpophalangeal joint of 18-month-old Tho...
Keegan KG, Yonezawa Y, Pai PF, Wilson DA.Video-based kinematic analysis of gait in horses is accurate for quantification of lameness and reliable for identification of the affected limb. Algorithms for the measurement of the vertical head and pelvic displacement and phase correlation with vertical displacement of one forelimb and hindlimb foot have been developed for this purpose. However, because of camera field-of-view limitations, video-based analysis of gait can only be reliably accomplished with the horse constrained to move on a treadmill. This paper describes the use of 2 single-axis accelerometers and 2 gyroscopic transducers...
White SH, Wohlgemuth S, Li C, Warren LK.Exercise is known to promote mitochondrial biogenesis in skeletal muscle as well as enhance mitochondrial function and efficiency in human and rodent models. These adaptations help to decrease exercise-associated production of reactive oxygen species, which can negatively affect health and performance if antioxidant mechanisms are overwhelmed. Little is known about the adaptations of mitochondria in response to exercise training in the growing horse or if supplementation with a dietary antioxidant can improve mitochondrial function. To evaluate the separate and combined effects of selenium (Se...
Janczarek I, Wiśniewska A, Tkaczyk E, Wnuk-Pawlak E, Kaczmarek B, Liss-Szczepanek M, Kędzierski W.Cooling a horse after intensive exercise under hot conditions is commonly recommended. The study aimed to analyze changes in the rectal and surface temperature of the horses subjected to various water cooling treatments. This followed medium-intensity exercise performed by leisure horses under moderate air temperature. The experiment involved a control group without water application, and three variants of water cooling applied to 19 warmblood geldings after medium-intensity effort. Cooling of lower, upper, and lower and upper body parts was performed. In each variant, the rectal and body surf...
Serteyn D, Sandersen C, Lejeune JP, de la Rebière de Pouyade G, Ceusters J, Mouithys-Mickalad A, Niesten A, Fraipont A, van Erck E, Goachet AG....Intense physical exercise can induce the degranulation of neutrophils leading to an increase in plasma concentration of the neutrophil marker enzymes myeloperoxidase (MPO) and elastase (ELT). These enzymes have pro-oxidative and pro-inflammatory properties and may play a role in the exercised-induced muscular damage. Objective: To measure MPO and ELT concentrations in plasma and muscles of endurance horses and to correlate them to the extent of exercise-induced muscular damage. Methods: Seven endurance horses qualified on 120 km races were tested in this study. Neutrophil count, serum creatine...
Alberghina D, Giannetto C, Piccione G.The purpose of this study was to evaluate the influence of exercise on plasma tryptophan (TRP) and free serotonin (f5-HT), whole blood-5-HT (WB-5-HT) and f5-HT/WB-5-HT ratio in Italian Saddle horses. Six clinically healthy Italian Saddle horses were subjected to a 450 meters obstacles course. Blood samples were collected from each horse by jugular venipuncture using vacutainer tubes with K(3)-EDTA at rest, immediately after exercise, and after 30 min. TRP, f5-HT and WB-5-HT were analyzed by HPLC. Immediately after exercise, statistically significant increases of f5-HT (p <0.001) and WB-5-HT (p...
