Exercise physiology in horses involves the study of the physiological responses and adaptations of horses to physical activity. This field examines how exercise impacts various systems in the equine body, including the cardiovascular, respiratory, muscular, and metabolic systems. Researchers focus on understanding how these systems interact during different types and intensities of exercise, and how they contribute to performance and recovery. Key areas of interest include the assessment of aerobic and anaerobic capacity, muscle fiber composition, energy metabolism, and thermoregulation. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms of exercise physiology in horses, with an emphasis on performance optimization, training regimens, and the prevention of exercise-related disorders.
Siegers E, van Wijk E, van den Broek J, Sloet van Oldruitenborgh-Oosterbaan M, Munsters C.Friesian stallions have to complete a 10-week studbook approval test (70-day test) consisting of dressage and driving training for acceptance as a breeding stallion. Training response of the horses to this approval program was evaluated. External workload (EW) of 16 stallions (3.2 ± 0.4 years old) was registered during the 9 weeks preceding the 70-day test (preparation period) and during 70-day test. Ridden indoor standardized exercise tests (SET), measuring heart rate (HR) and plasma lactate concentration (LA) at walk, trot and canter, were performed in week 1 (SET-I), 6 (SET-II) and 10 (SET...
Johnson SE, Barshick MR, Gonzalez ML, Riley JW, Pelletier ME, Castanho BC, Ealy EN.Strenuous exercise can cause tissue damage, leading to an extended recovery period. To counteract delayed post-exercise recovery, a commercial product containing L-carnitine (AID) was tested in adult horses performing consecutive exercise tests to exhaustion. Fit Thoroughbreds were administered an oral bolus of placebo (CON) or AID prior to performing an exercise test to exhaustion (D1). The heart rate (HR) and fetlock kinematics were captured throughout the exercise test. Blood was collected before, 10 min and 1, 4 and 6 h relative to exercise for the quantification of cytokine (1, 8, 10, ) g...
Siegers E, van den Broek J, Sloet van Oldruitenborgh-Oosterbaan M, Munsters C.Young Friesian stallions have to complete a 10-week training program (70-day test) for acceptance as a breeding stallion. Part one of this study showed that the 70-day test was too intense and led to reduced fitness. In the present (part two) study, the effects of an adapted training program were studied. Training frequency and minutes of cantering per week were lowered compared with part one. The external workload (EW) of sixteen stallions (3.4 ± 0.8 years) was monitored during the 6-weeks before testing (preparation period) as well as during the 70-day test. Standardized exercise tests (SET...
Marichal G, Trigo P, Soto C, Meikle A, Suárez G.The Raid Uruguayo (RAID) is an equestrian endurance competition. This study characterized the hydroelectrolytic parameters (Na, K, Cl, tCa, and iCa), hematocrit (Ht), total plasma protein (TPP), and blood pH from 900 equine athletes (finishers and non-finishers) competing over distances of 80 to 115 km under different climate conditions. Paired blood samples were taken prior to the start of the competition (sample 1) and at the end of the race or at the time of leaving the competition (sample 2). The association of the comfort index (CI: low, moderate, and high) with blood parameters was evalu...
Rohlf CM, Garcia TC, Fyhrie DP, le Jeune SS, Peterson ML, Stover SM.Mechanical properties of arena surfaces are extrinsic factors for musculoskeletal injury. Vertical impact forces of harrowed and compacted cushion were measured at five locations on 12 arena surfaces (five dirt, seven synthetic [dirt and fiber]). Eight variables related to impact force, displacement, and acceleration were calculated. Surface temperature, cushion depth and moisture content were also measured. The effects of surface material type (dirt/synthetic) and cushion compaction (harrowed/compacted) on vertical impact properties were assessed using an analysis of variance. Relationships o...
Burnley M.The parameters of the hyperbolic speed-duration relationship (the asymptote critical speed, CS, and the curvature constant, D') provide estimates of the maximal steady state speed (CS) and the distance an animal can run, swim, or fly at speeds above CS before it is forced to slow down or stop (D'). The speed-duration relationship has been directly studied in humans, horses, mice and rats. The technical difficulties with treadmill running in dogs and the relatively short greyhound race durations means that, perhaps surprisingly, it has not been assessed in dogs. The endurance capabilities of li...
McCrae P, Spong H, Golestani N, Mahnam A, Bashura Y, Pearson W.Electrocardiograms (ECGs), and associated heart rate (HR) and heart rate variability (HRV) measurements, are essential in assessing equine cardiovascular health and fitness. Smart textiles have gained popularity, but limited validation work has been conducted. Therefore, the objective of this study was to compare HR and HRV data obtained using a smart textile system (Myant) to the gold-standard telemetric device (Televet). Simultaneous ECGs were obtained using both systems in seven horses at rest and during a submaximal exercise test. Bland-Altman tests were used to assess agreement between th...
Adah AS, Ayo JO, Adah DA, Nwonuma CO, Lawal TA.Exercise-induced oxidative stress is a challenge in equine sports. This study aims at determining the effects of ergothioneine on heat shock protein-70 (HSP-70) following the stress of an endurance exercise of 30 km by Arabian stallions. Molecular docking was also done to investigate the interaction between the ligand ergothioneine and heat shock protein-70 using sulfogalactosylceramide and sulfogalactoglycerolipid as standards. The study involved a total of 18 clinically healthy stallions, with an average age of 6.7 ± 2.4 years and an average weight of 411.54 ± 12.46 kg. Only cli...
Cullinane A, Garvey M, Walsh C, Gibbons J, Creighton A.The association between poor performance and respiratory disease in Thoroughbred racehorses that do not have a structural abnormality of the respiratory tract, is often based on anecdotal evidence. The objective of this scoping review was to examine the scientific evidence for such associations. Publications were selected based on a search of three databases (PubMed, Scopus, and CAB Direct), in English and without date restriction, followed by a screening process to exclude non-relevant papers, duplicates, and reviews. This process identified 996 publications of which 20 were analysed using th...
Henry ML, Wesolowski LT, Pagan JD, Simons JL, Valberg SJ, White-Springer SH.Coenzyme Q10 (CoQ10) is an essential component of the mitochondrial electron transfer system and a potent antioxidant. The impact of CoQ10 supplementation on mitochondrial capacities and the muscle proteome is largely unknown. This study determined the effect of CoQ10 supplementation on muscle CoQ10 concentrations, antioxidant balance, the proteome, and mitochondrial respiratory capacities. In a randomized cross-over design, six Thoroughbred horses received 1600 mg/d CoQ10 or no supplement (control) for 30-d periods separated by a 60-d washout. Muscle samples were taken at the end of each peri...
Muhonen S, Julliand V.Racing events challenge the fluid balance of athletic horses. The equine large intestine functions as a fluid reservoir, since the properties of dietary forage fibre affect the digesta water content and the milieu of this ecosystem. This study aimed to investigate the effect of grass maturity and legume forage on the faecal water-holding capacity (WHC) and microbial ecosystem, and the fluid balance and body weight (BW) of French trotters in race training. Six geldings were offered three diets with different fibre compositions: concentrate and late-harvested mature grass haylage (35:65 energy r...
Salz RO, Elliott CRB, Zuffa T, Bennet ED, Ahern BJ.Overstrain of the superficial digital flexor tendon (SDFT) is a common Thoroughbred racehorse limb injury requiring treatment. Objective: To determine whether treatment of SDFT lesions in flat Thoroughbred racehorses with autologous bone marrow-derived mesenchymal stem cells (BM-MSCs) or allogenic adipose-derived mesenchymal stem cells (A-MSCs) is associated with improved likelihood of returning to racing, when compared to racehorses managed with a controlled exercise rehabilitation program (CERP) alone. Methods: Retrospective cohort study combining clinical treatment records with race records...
Wilson J, De Donato M, Appelbaum B, Garcia CT, Peters S.Overtraining syndrome (OTS) is the reduction in performance due to excess training and lack of proper recovery, which can lead to a chronic deprivation of energy and reduction in the repair of damage that can accumulate over time. Here, the effect of acute, intense physical exercise on the expression of innate and adaptive immune genes in 12 racing-bred American Quarter Horses, after resting for 3 days and immediately after intense exercise for 1.8 miles were compared. The expression of 84 genes related to innate and adaptive immune responses was analyzed. Significant variation among individua...
Hammond A, Sage W, Hezzell M, Smith S, Franklin S, Allen K.Heart rate variability (HRV) analysis measures the inter-beat interval variation of successive cardiac cycles. Measurement of these indices has been used to assess cardiac autonomic modulation and for arrhythmia identification in exercising horses. Objective: To report HRV indices during submaximal exercise, strenuous exercise and recovery, and explore relationships with clinical conditions (arrhythmias, lameness, equine gastric ulcer syndrome [EGUS], lower airway inflammation and upper respiratory tract obstructions [URTOs]) in Thoroughbred racehorses. Methods: Retrospective, observational cr...
Ayo JO, Ake AS, Abimbola AA.The study aimed to evaluate effects of packing (load-carrying) and trekking on hematological and biochemical parameters in donkeys during the hot-dry season. Ten pack donkeys, aged 2-3 years, weighing 93 ± 2.7 kg were enrolled in the study and randomly divided into two groups of five animals each. Group 1 donkeys were subjected to packing + trekking while group 2 trekked only. All the donkeys trekked 20 km thrice, 1-day apart. Blood was collected before and after packing or trekking for hematological evaluation; and serum analyzed for electrolyte concentrations, and aspartate aminotransfera...
Kent E, Coleman S, Bruemmer J, Casagrande RR, Levihn C, Romo G, Herkelman K, Hess T.Antioxidant supplementation decreases postexercise oxidative stress but could also decrease muscle protein synthesis. This study compared the effects of three diets: low antioxidant (control, CON), high antioxidant (AO), and branched-chain amino acid high antioxidant (BCAO) supplementation on postexercise protein synthesis and oxidative stress. We hypothesized that supplementing antioxidants with branched-chain amino acids(BCAA) would reduce oxidative stress without hindering muscle protein synthesis. Eighteen mixed-breed polo horses (11 mares and 7 geldings, with age range between 5 and 18 ye...
Waller AP, Lindinger MI.Oral electrolyte supplementation may influence acid-base state during exercise due to the intestinal absorption of administered water and electrolytes used to mitigating sweat losses. This study examined the effect of pre-exercise electrolyte supplementation (3 and 8 L) on plasma acid-base variables at rest, during moderate intensity exercise and during recovery. It was hypothesized that electrolyte supplementation will result in improved acid-base state compared to the alkalosis typical of prolonged exercise. In randomized crossover fashion, four horses were administered 3 L or 8 L of a hypot...
Wang T, Zeng Y, Ma C, Meng J, Wang J, Ren W, Wang C, Yuan X, Yang X, Yao X.In this study, the plasma non-targeted metabolomics of Yili horses were characterized before and after exercise on tracks that differed in surface hardness to better understand exercise-related biochemical changes. Blood samples were obtained from eight trained Yili horses before and immediately after exercise. Samples were used for metabolomic analysis by ultra-performance liquid chromatography-Q-EXACTIVE mass spectrometry. In total, 938 significantly different metabolites involving sugar, lipid, and amino acid metabolism were detected in the plasma, with significant increases in glucose, glu...
Han H, McGivney BA, Allen L, Bai D, Corduff LR, Davaakhuu G, Davaasambuu J, Dorjgotov D, Hall TJ, Hemmings AJ, Holtby AR, Jambal T, Jargalsaikhan B....Selection for system-wide morphological, physiological, and metabolic adaptations has led to extreme athletic phenotypes among geographically diverse horse breeds. Here, we identify genes contributing to exercise adaptation in racehorses by applying genomics approaches for racing performance, an end-point athletic phenotype. Using an integrative genomics strategy to first combine population genomics results with skeletal muscle exercise and training transcriptomic data, followed by whole-genome resequencing of Asian horses, we identify protein-coding variants in genes of interest in galloping ...
Plisak U, Szczepaniak J, Żmigrodzka M, Giercuszkiewicz-Hecold B, Witkowska-Piłaszewicz O.Several anti-inflammatory cytokines have been proposed as markers for exercise monitoring in humans such as the interleukin 1 receptor agonist (IL-ra), or interleukin 13 (IL-13). Equine athletes may be considered a model for human exercise physiology research, however there is a lack of such studies of this species. Thus, we decided to examine the changes of IL-1ra and IL-13 in serum concentration during aerobic (endurance) and anaerobic (race) exercise in horses of different fitness levels in comparison with the well-known anti-inflammatory cytokine interleukin 10 (IL-10). The group of endura...
Macaire C, Hanne-Poujade S, De Azevedo E, Denoix JM, Coudry V, Jacquet S, Bertoni L, Tallaj A, Audigié F, Hatrisse C, Hébert C, Martin P, Marin F....Defining whether a gait asymmetry should be considered as lameness is challenging. Gait analysis systems now provide relatively accurate objective data, but their interpretation remains complex. Thresholds for discriminating between horses that are visually assessed as being lame or sound, as well as thresholds for locating the lame limb with precise sensitivity and specificity are essential for accurate interpretation of asymmetry measures. The goal of this study was to establish the thresholds of asymmetry indices having the best sensitivity and specificity to represent the visual single-lim...
Coelho CS, Silva ASBA, Santos CMR, Santos AMR, Vintem CMBL, Leite AG, Fonseca JMC, Prazeres JMCS, Souza VRC, Siqueira RF, Manso Filho HC, Simões JSA.The purpose of this study was to investigate stressful responses during a 6-week training protocol in young Lusitano horses used for dressage. The hypothesis was that the proposed training protocol would improve fitness and ensure the welfare of the animals by reducing stress predictors. Nine 4-year-old horses were evaluated before (M1) and six weeks after (M2) beginning a training protocol. The training program was performed six times per week and included 40−80 min of individually intensity-adjusted preparatory exercises for dressage. For both moments, the horses were examined before (T0) ...
Elmeua González M, Šarabon N.How the modification of saddle fitting parameters in horse riding affects rider's kinetics is very uncertain. The aim of this study is to describe how manipulating the two main adjustments that an end-user is likely to perform (saddle tilt and stirrup length) affects the biomechanics of a horse rider on a living horse. Eleven showjumpers volunteered to take part in this study. Each participant performed a 120-strides standardization trial at trot and canter, with 0° saddle tilt and stirrup length that would position the rider's knee at 90°. Following the standardization trial, four intervent...
Orr EL, Staniar WB, Smarsh DN.Understanding the frequency, duration, and intensity of exercise is important for determining the optimal diet and management of horses. The objective of the study was to characterize the exercise management of horses in Pennsylvania. An online survey was distributed from February 27th to August 31st, 2020. Respondents were asked to place their horse in an exercise category, as well as report on frequency and duration of exercise and time spent at each gait. Nonparametric statistics (mdn=median) and tests were used when data were not normally distributed. Of the 470 horses, 68% were regularly ...
Heidbuchel A, Van Rossom S, Molenaers N, Minguet P, Jonkers I.In dressage riding, rider posture plays an important role in the performance of the exercises. The purpose of this study was to compare physical fitness and posture on an equestrian simulator between different competitive dressage rider skill levels. Participants (ten expert and twelve novice competitive dressage riders) performed a physiotherapeutic screening test and an equestrian simulator test. The expert rider group (G2) had less variability in both left (P = .002) and right (P = .021) rein force during medium canter on the simulator compared to the novice rider group (G1). The should...
Riders’ asymmetry may cause back pain in both human and equine athletes. This pilot study aimed at documenting in a simple and quick way asymmetry in riders during a simulation of three different riding positions on wooden horseback using load cells applied on the stirrup leathers and identifying possible associations between riders’ asymmetry and their gender, age, level of riding ability, years of riding experience, riding style, motivation of riding, primary discipline and handedness. After completing an interview to obtain the previously mentioned information, 147 riders performed a st...
Lo Feudo CM, Stucchi L, Conturba B, Stancari G, Zucca E, Ferrucci F.Equine Gastric Ulcer Syndrome (EGUS) is a highly prevalent disorder in horses, which can be classified, based on the localization of the lesions, as Equine Squamous Gastric Disease (ESGD) or Equine Glandular Gastric Disease (EGGD). Although EGUS is recognized as a common cause of poor performance in racehorses, objective investigations about its relation with athletic capacity are lacking. Therefore, the present retrospective study aims to evaluate the associations between EGUS severity and some fitness parameters measured during an incremental treadmill test in Standardbred racehorses in trai...
McCrae P, Spong H, Rutherford AA, Osborne V, Mahnam A, Pearson W.Electrocardiography (ECG) is an essential tool in assessing equine health and fitness. However, standard ECG devices are expensive and rely on the use of adhesive electrodes, which may become detached and are associated with reduced ECG quality over time. Smart textile electrodes composed of stainless-steel fibers have previously been shown to be a suitable alternative in horses at rest and during exercise. The objective of this study was to compare ECG quality using a smart textile girth band knit with silver and carbon yarns to standard adhesive silver/silver chloride (Ag/AgCl) electrodes. S...
Martins JN, Silva SR.Equitation is a cause of physiological stress in the equine athlete, and personality is a factor generally associated with the different responses of equines to stressors. This study explored ocular temperature, measured via infrared thermography, associated with personality and stress in horses submitted to dressage exercising in riding lessons, ridden training and lunging. Infrared thermograms of 16 horses were taken before and after sessions using an FLIR F4 camera (FLIR Systems AB, Sweden) to determine maximum eye surface IRT temperature (IRTmax), and total training time was registered (T)...
Kapteijn CM, Frippiat T, van Beckhoven C, van Lith HA, Endenburg N, Vermetten E, Rodenburg TB.Measuring physiological parameters of stress in horses during groundwork, for example when involved in equine-assisted interventions, is important to gain insight into the stress levels of the horses. Heart rate and heart rate variability can be used as physiological indicators of stress in horses. Heart rate monitors could be easily incorporated into practice, as they are not expensive and easy to use. However, it is questionable whether heart rate monitors present accurate heart rate variability results in exercising horses, similar to electrocardiograms. The aim of this study was to determi...
Murray RC, Vedi S, Birch HL, Lakhani KH, Goodship AE.It was hypothesised that subchondral bone thickness, hardness and remodelling are influenced by exercise intensity, and by location within a joint. Dorsal carpal osteochondral injury is a major cause of lameness in horses undergoing high intensity training. This project aimed to determine the subchondral bone thickness, formation, resorption and hardness at sites with high and low incidence of pathology in 2 year-old horses undergoing 19 weeks high intensity treadmill training or low intensity exercise, and to compare these factors between exercise groups. Dorsal and palmar test sites were ide...
Devienne MF, Guezennec CY.Oxygen consumption (VO2), ventilation (VE) and heart rate (HR) were studied in five recreational riders with a portable oxygen analyser (K2 Cosmed, Rome) telemetric system, during two different experimental riding sessions. The first one was a dressage session in which the rider successively rode four different horses at a walk, trot and canter. The second one was a jumping training session. Each rider rode two horses, one known and one unknown. The physiological parameters were measured during warm up at a canter in suspension and when jumping an isolated obstacle at a trot and canter. This s...
Keegan KG, Pai PF, Wilson DA, Smith BK.In horses at a trot, the head moves up and down twice in one stride. In horses with unilateral forelimb lameness this movement is asymmetric. Computer-assisted kinematic analysis of vertical head movement can be used to quantify objectively lameness in horses in clinical trials. However, in mild lameness, absolute measurements of vertical head height may not be sensitive enough to detect small differences in lameness, and extraneous head movement by the horse due to curiosity, excitement or nervousness interferes with the accurate measurement of vertical head movement asymmetry. We describe a ...
van Heel MC, van Dierendonck MC, Kroekenstoel AM, Back W.Foot stance in grazing significantly influences hoof conformation and development from foal to yearling age. Objective: To conduct a longitudinal study to establish if the relationship between motor laterality and uneven front feet persisted in 3-year-old horses at the time of studbook selection and to investigate if such laterality and unevenness might influence the horses' ability to perform symmetrically while trotting, cantering and free jumping. Methods: Seventeen clinically sound but untrained (with only minimal experience of handling) and sound Warmblood horses that had participated in ...
Young LE, Rogers K, Wood JL.Cardiac morphology in human athletes is known to differ, depending on the sports-specific endurance component of their events, whereas anecdotes abound about superlative athletes with large hearts. As the heart determines stroke volume and maximum O(2) uptake in mammals, we undertook a study to test the hypothesis that the morphology of the equine heart would differ between trained horses, depending on race type, and that left ventricular size would be greatest in elite performers. Echocardiography was performed in 482 race-fit Thoroughbreds engaged in either flat (1,000-2,500 m) or jump racin...
Powell DM, Reedy SE, Sessions DR, Fitzgerald BP.Twelve untrained aged mares were used to determine whether 7 days of light exercise improved peripheral tissue insulin sensitivity. Mares were divided into obese-exercised (n = 3), obese-sedentary (n = 3), lean-exercised (n = 3) and lean-sedentary (n = 3) groups. The exercised groups were worked at a trot to a heart rate (HR) of not more than 140 beats/min for 30 min in a round pen. Each group was subjected to 3 euglycaemic hyperinsulinaemic clamps: prior to exercise (P), 24 h following the seventh exercise training session (E) and 9 days postexercise training (PE). Prior to exercise training,...
Mathieu-Costello O, Hoppeler H, Weibel ER.Capillary orientation (anisotropy) was compared in hindlimb muscles of mammals of different size and/or different aerobic capacity (dog, goat, pony, and calf). All muscles were fixed by vascular perfusion at sarcomere lengths ranging from 1.5 to 2.7 micron. The ratios of capillary counts per fiber cross-sectional area on two sets of sections (0 and 90 degrees) to the muscle fiber axis were used to estimate capillary anisotropy and the coefficient c(K,0) relating 1) capillary counts on transverse sections (a commonly used parameter to assess muscle capillarity) and 2) capillary length per volum...
McGivney BA, Browne JA, Fonseca RG, Katz LM, Machugh DE, Whiston R, Hill EW.Myostatin, encoded by the MSTN gene, is a member of the TGF-β superfamily that regulates skeletal muscle development. A MSTN SNP significantly associated with Thoroughbred horse racing phenotypes has recently been identified as well as significant reductions in Thoroughbred skeletal muscle gene expression for three transcripts 400-1500 base pairs downstream of the MSTN gene following a period of training. Together, these findings indicate that MSTN genotypes may influence MSTN gene expression. To investigate this, MSTN mRNA expression was measured in biopsies from the middle gluteal muscle fr...
Morgan RA, Keen JA, McGowan CM.Treatment of equine metabolic syndrome (EMS) is essential to improve insulin sensitivity and reduce the risk of laminitis. Calorie restriction and increased exercise are the mainstays of treatment but there is potential for poor owner compliance. Objective: To determine whether significant weight loss accompanied by improvements in measures of insulin sensitivity can be achieved in horses and ponies with EMS managed by their owners in their normal environment under veterinary guidance. Methods: Retrospective clinical case series. Methods: Horses and ponies attending 2 university hospitals for ...
Franklin SH, Van Erck-Westergren E, Bayly WM.Horses are elite athletes when compared with other mammalian species. In the latter, performance is limited by cardiovascular or musculoskeletal performance whereas in athletic horses it is the respiratory system that appears to be rate limiting and virtually all horses exercising at high intensities become hypoxaemic and hypercapnoeic. This is due to both diffusion limitation and a level of ventilation inadequate for the metabolic level that enables horses to exercise at these intensities. In conjunction with these blood gas changes, total pulmonary resistance increases and the work of breath...
Richard EA, Fortier GD, Pitel PH, Dupuis MC, Valette JP, Art T, Denoix JM, Lekeux PM, Erck EV.The objectives of this study were to determine the prevalence of sub-clinical diseases in poorly-performing Standardbred horses, compare their physiological response to exercise with control horses, and identify predictive parameters of poor-performance. Fifty horses underwent thorough clinical and ancillary examinations, including haematological and biochemical evaluation, Doppler echocardiography, standardised exercise tests (SETs) on both treadmill and racetrack, treadmill video-endoscopy and collection of respiratory fluids. Most of the poorly-performing horses exhibited many concomitant d...
Ohmura H, Jones JH.We investigated changes in heart rate (HR) and HR variability as a function of age in newborn foals to old Thoroughbred horses. Experiments were performed on a total of 83 healthy and clinically normal Thoroughbred horses. Resting HR decreased with age from birth. The relationship between age and HR fit the equation Y=48.2X(R=0.705); the relationship between age and HR for horses 0-7 years old fit the equation Y=44.1X(R=0.882). Seven-day-old horses had the highest HR values (106 ± 10.3 beat/min). The low frequency (LF) and high frequency (HF) powers increased with age in newborn to old horses...
Robert C, Valette JP, Denoix JM.Electromyographic activity (EMG) was used to determine how hindlimb muscle activation patterns vary with speed and incline in the horse. EMG was recorded using surface electrodes over the gluteus medius and tensor fasciae latae muscles during treadmill locomotion at trot for different combinations of speed (3.5 to 6 m/s) and inclination (0, 3 and 6%). Raw EMG signals were processed to determine stride duration, activity onset and end, and integrated EMG (IEMG). Stride and stance phase duration decreased linearly with increasing speed. Stride duration was not influenced by the slope. Onset and ...
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...
Valberg SJ.Optimal function of skeletal muscle is essential for successful athletic performance. Even minor derangements in locomotor muscle function will impact power output, coordination, stamina, and desire to work during exercise. In this review, the presenting clinical signs, differential diagnoses, approach to diagnostic testing and treatment of muscle atrophy and weakness, focal muscle strain, and exertional myopathies are discussed. Exertional myopathies include polysaccharide storage myopathies, recurrent exertional rhabdomyolysis, malignant hyperthermia, and myofibrillar myopathy.
Holmström M, Fredricson I, Drevemo S.The trotting gait of 4 approved Swedish Warmblood stallions with a mean gait score > or = 8.67 (maximum score = 10) at official performance tests was recorded by high speed film (approximately 250 frames/sec). Angular patterns and hoof trajectories of the left fore and hind limbs were analysed, and presented as mean and standard deviation curves. The horses had a mean stride duration of 794.0 msec (sd 13.7) and the mean diagonal advanced placement was +29.8 msec (sd 7.6). The variation in angular patterns between the horses was greatest during the swing phase. The trajectory of the hind hoof r...
Arfuso F, Giudice E, Panzera M, Rizzo M, Fazio F, Piccione G, Giannetto C.The monitoring of endocrine and immunologic markers during exercise is of paramount importance to assess and/or maintain the physical well-being of athletes as well as to optimize the athletic performance. This study aimed to investigate the linkage between acute stress response and immune status in Thoroughbred horses competing in an official 1300-m race. From 10 horses blood was collected 1 week before the day of the race (1W-BEFORE), before (REST) and immediately after the race to assess the cortisol, Interleukin-1 receptor antagonist (IL-1Ra), total proteins, white blood cells (WBC), red b...
Setterbo JJ, Garcia TC, Campbell IP, Reese JL, Morgan JM, Kim SY, Hubbard M, Stover SM.To compare hoof acceleration and ground reaction force (GRF) data among dirt, synthetic, and turf surfaces in Thoroughbred racehorses. Methods: 3 healthy Thoroughbred racehorses. Methods: Forelimb hoof accelerations and GRFs were measured with an accelerometer and a dynamometric horseshoe during trot and canter on dirt, synthetic, and turf track surfaces at a racecourse. Maxima, minima, temporal components, and a measure of vibration were extracted from the data. Acceleration and GRF variables were compared statistically among surfaces. Results: The synthetic surface often had the lowest peak ...
Buhl R, Ersbøll AK.To assess whether physical training induces cardiac hypertrophy and valvular regurgitation in maturing Standardbred trotters and to establish a prediction model for the size of the left ventricle. Methods: Longitudinal observational study. Methods: 53 Standardbred trotters. Methods: Each horse underwent 2-D, M-mode, and color flow Doppler echocardiography at 5.5 years of age; previously, each horse had been examined at 2, 2.5, 3, and 3.5 (time of maturity) years of age. Horses were or were not in training or racing for variable periods during the entire assessment period; data for a given hors...
Robert C, Valette JP, Denoix JM.The purpose of this study was to evaluate the effects of speed and slope on the activity of trunk muscles. The electromyographic (EMG) activity of the splenius (Sp), longissimus dorsi (LD) and rectus abdominis (RA) muscles was recorded with surface electrodes during treadmill locomotion at trot for different combinations of speed (3.5 to 6 m/s) and slope (0 to 6%). Raw EMG signals were processed to determine activity duration, onset and end and integrated EMG (IEMG). For the 3 muscles investigated, onset and end of activity were obtained earlier in the stride cycle when speed increased. A long...
Biknevicius AR, Mullineaux DR, Clayton HM.Gaited horses employ 4-beat stepping (singlefoot) gaits that extend into speeds typical of trots. Ground reaction force (GRF) patterns of these specialised gaits have not been reported; therefore, appraisal of these gaits using nongaited horse kinetics may lead to clinical misjudgements. Objective: GRFs of tölting Icelandic horses will be comparable in profile and magnitude with those of trotting horses. Methods: Forelimb and hindlimb GRFs were obtained for 10 Icelandic horses ridden at a tölt. These data were evaluated across 3 speed ranges: <2, 2.5-5 and >5 m/sec. Results: Virtually all ve...
Evans DL, Rose RJ.Cardiovascular and respiratory responses to submaximal exercise training were investigated in 6 thoroughbred racehorses. Oxygen uptake, heart rate (HR) and arteriovenous oxygen content difference were measured during incremental treadmill exercise tests, before and after 7 weeks of treadmill training. Cardiac output during exercise was calculated by the direct Fick technique. Maximal oxygen uptake (VO2max) was increased by 23% after training, from 129.7 ml/kg/min to 160.0 ml/kg/min. The treadmill speed at which VO2max was attained increased by 19%. The increased aerobic power after training wa...
de Graaf-Roelfsema E, Keizer HA, van Breda E, Wijnberg ID, van der Kolk JH.Overtraining is an imbalance between training and recovery leading to symptoms associated with a neuroendocrine dysbalance called the overtraining syndrome, a disease characterized by behavioral, emotional and physical symptoms similar with depression. Although the prevalence of overtraining is high in human and equine athletes, at present no sensitive and specific test is available to prevent or diagnose overtraining. Nowadays, it is believed that combination of different (hormonal) parameters appear to be the best indicators of overtraining. Therefore, this review provides a summary of previ...
Nolen-Walston RD, Harris M, Agnew ME, Martin BB, Reef VB, Boston RC, Davidson EJ.To determine whether there are important differences relating to seasonality of signs or clinical features between subtypes of inflammatory airway disease (IAD) in horses caused by neutrophilic and eosinophilic-mastocytic inflammation having dissimilar etiopathologic pathways. Methods: Retrospective case series. Methods: 98 horses. Methods: Data were compiled from medical records of horses examined because of poor performance from 2004 through 2010. Horses underwent a standardized high-speed treadmill test, lameness evaluation, cardiac evaluation, and postexercise bronchoalveolar lavage (BAL)....
Tan RH, Dowling BA, Dart AJ.The purpose of the study was to describe the prevalence of upper airway abnormalities and establish if any significant associations existed between study variables and the two most frequently identified disorders; axial deviation of the aryepiglottic folds and dorsal displacement of the soft palate. The clinical records and video-recordings of all horses referred for upper respiratory tract evaluation during high-speed treadmill videoendoscopy between November 1997 and September 2003 were reviewed. Of 291 horses included in the study, 265 underwent resting endoscopy and 42% (112/265) had a rec...
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...
Zsoldos RR, Kotschwar A, Kotschwar AB, Rodriguez CP, Peham C, Licka T.The rectus abdominis (RA) and oblique external abdominal (OEA) muscles are both part of the construction of the equine trunk and thought to be essential for the function of the spine during locomotion. Although RA activity at trot has previously been investigated, the relationship between OEA and RA at walk and trot has not yet been described. Objective: To document abdominal muscle activities during walk and trot, and test the hypothesis that muscle activity at walk would be smaller than at trot. Methods: Six horses (8-20 years old, 450-700 kg) were used for surface electromyography (EMG) mea...
Robert C, Valette JP, Degueurce C, Denoix JM.The purpose of this study was to demonstrate the feasibility of surface electromyography in the horse and to correlate electromyographic activity with kinematic data. Surface electromyography of seven hindlimb muscles was recorded in five horses at trot on a treadmill. Simultaneously, kinematic analysis of the hindlimb was performed using a three-dimensional system and a unidirectional accelerometer was attached to the hoof. Electromyographic activities of the gluteus medius, vastus lateralis and two parts of the biceps femoris started in the late part of the swing phase and ended in the late ...
Almeida ML, Feringer WH, Carvalho JR, Rodrigues IM, Jordão LR, Fonseca MG, Carneiro de Rezende AS, de Queiroz Neto A, Weese JS, Costa MC, Lemos EG....Recent studies performed in humans and rats have reported that exercise can alter the intestinal microbiota. Athletic horses perform intense exercise regularly, but studies characterizing horse microbiome during aerobic conditioning programs are still limited. Evidence has indicated that this microbial community is involved in the metabolic homeostasis of the host. Research on ergogenic substances using new sequencing technologies have been limited to the intestinal microbiota and there is a considerable demand for scientific studies that verify the effectiveness of these supplements in horses...
Redaelli V, Luzi F, Mazzola S, Bariffi GD, Zappaterra M, Nanni Costa L, Padalino B.The aim of this pilot study was to document the effects of endurance training at different intensities on heart rate (HR), blood count, serum cortisol, and maximal temperatures of different body locations, namely eye, crown, pastern pasterns, and muscle (, measured by infrared thermography technique (IRT) in horses trained for endurance. Possible associations among the studied parameters were also investigated. Our hypothesis was that temperature, measured by IRT after endurance training of different intensities would vary depending on the intensity and would be positively correlated with HR...
