Treadmill exercise for horses involves the use of a controlled mechanical platform to simulate various gaits and intensities of physical activity. This form of exercise allows for consistent and measurable training conditions, which can be used for rehabilitation, fitness assessment, and performance enhancement. Treadmill exercise facilitates the study of equine locomotion, respiratory function, and cardiovascular response under standardized conditions. It is also utilized in research to evaluate the effects of different training regimens and to investigate metabolic and physiological responses to exercise. This page compiles peer-reviewed research studies and scholarly articles that explore the methodology, applications, and implications of treadmill exercise in equine practice.
Ebisuda Y, Kitaoka Y, Takahashi Y, Sugiyama F, Yoshida T, Mukai K.Heat acclimation enhances thermoregulation and cardiovascular function. While daily training protocols are typically recommended for humans, optimal training protocols for Thoroughbred horses remain unclear. Here, we compared the effects of two heat acclimation protocols, consecutive and intermittent, in Thoroughbred horses. In a randomized crossover study, eight trained Thoroughbred horses completed either a consecutive (CONS: 9 consecutive days) or an intermittent (INT: 3 days/week for 3 weeks) heat acclimation protocol, comprising 30 min of exercise in hot conditions (WBGT 30°C). Increment...
Nascimento C, Braz AL, Barbosa I, Freire G, Nicolau M, Silvestre F, Filho HM, Simões J, Estepa JC, Clayton H, Coelho C.This study aimed to investigate cardiac adaptations and energy expenditure of jumping horses after water treadmill (WT) training. Six trained horses were evaluated before (PRETR) and after (TR) a WT training (20 min, twice/week, water at carpus height) for 10 weeks. Transthoracic echocardiography was performed at PRETR and TR with phased array transducer (1.9-4 MHz) to obtain interventricular septal thickness (IVS), LV internal diameter (LVID), and posterior wall thickness (LVPW) at end-diastole (d) and systole (s) and heart rate (HR). Left ventricule end diastolic volume (Vd) and end syst...
Lungu GM, Barshick MR, Shafron AJ, El-Kadi SW, Williams BD, Wesolowski LT, Disilvestro AN, White-Springer SH, Johnson SE.High-intensity exercise in horses resulting in fatigue requires a better understanding of biomarkers defining the condition such that protocols detailing the return to work can be established. This study examined blood metabolite profiles after multiple sessions of high-intensity exercise to define physiological exhaustion. Adult Thoroughbred geldings (n = 10) underwent a standardized exercise test (SET) on a high-speed treadmill, with BHB, BCAAs, alanine, lactate, and CK measurements at regular intervals up to 6 h post-SET. Before and 24 h post-SET gluteus medius muscle samples were t...
Mukai K, Takahashi Y, Ebisuda Y, Sugiyama F, Yoshida T, Miyata H.This study tested the hypothesis that 6 weeks of high-intensity interval training (HIIT) would induce greater physiological adaptations than moderate-intensity continuous training (MICT) in Thoroughbred horses. Seven untrained horses completed two distance-matched treadmill training protocols (three sessions per week) in a randomized crossover design, separated by a three-month washout: MICT (6 min at 70% ) and HIIT (6 × [30 s at 100% with 30 s at 30% ]). Incremental exercise tests were conducted at weeks 0, 3, and 6 to assess exercise performance and physiological responses. M...
Campos Schweitzer A, Mespoulhes-Rivière C, Perkins JD, Ducharme NG, Piercy RJ, Lynch N, Rossignol F.To evaluate functional and histopathologic outcomes of standing selective laryngeal reinnervation using the spinal accessory nerve (SAN) in horses with experimentally induced recurrent laryngeal neuropathy (RLN). Methods: Five Thoroughbred mares. Methods: Prospective cohort study. Methods: The horses underwent left recurrent laryngeal neurectomy followed 8 weeks later by selective laryngeal reinnervation using the SAN. Follow-up evaluations at 4.5, 6, 8, and 12 months included treadmill exercising endoscopy, ultrasonography of intrinsic laryngeal muscles, and percutaneous electrical stimul...
Vargas J.To describe the application of water treadmill exercise for equine fitness and/or rehabilitation in a scientific and clinically reasonable manner. Unassigned: Horses owned by Spy Coast Farm were used for video content. Unassigned: A literature review was performed and compiled in this brief video to provide veterinarians with a comprehensive, evidence-based guide for implementing water treadmill exercise within fitness and rehabilitation programs. Unassigned: Equine water treadmill exercise is an aerobic modality that increases distal limb flexion and range of motion, with no reported adverse ...
Libak Haugaard S, Schneider MJ, Nissen SD, Saljic A, Fruergaard Andersen P, Carstensen H, Hopster-Iversen C, Jespersen T, Larsen S, Buhl R.Mitochondrial respiration sustains the high energy demands of endurance exercise, yet the extent to which atrial, ventricular, and skeletal muscle mitochondria adapt remains uncertain. At the same time, endurance athletes face an increased risk of atrial fibrillation (AF), but the role of cardiac metabolism in arrhythmia susceptibility is poorly understood. Here, we compared mitochondrial respiration in skeletal muscle and across all four cardiac chambers between trained and untrained racehorses ( = 34) to investigate adaptations associated with long-term endurance exercise. We further examine...
Key K, Berg K, Kirkegaard J, Andresen KR, Hansen SS.Equine lameness diagnosis largely relies on subjective visual assessments, which can be biased. Although marker-based methods, force plates and inertial measurement units (IMUs) provide objective measurements, they require specialized setups. Vision-based algorithms offer a portable, markerless alternative, but their accuracy needs thorough testing. Objective: To evaluate a custom vision-based algorithm for estimating the groundline across multiple camera angles, including handheld use in horses trotting on a treadmill. Methods: Experimental comparative study. Methods: Eight Standardbred trott...
Littiere TO, da Costa GB, de Sales NAA, de Carvalho JRG, Rodriguez IDM, Ramos GV, de Lacerda-Neto JC, Ferraz GC.Maximal lactate steady state (MLSS) and its predictive thresholds, including the lactate threshold (LT), are widely used to estimate endurance capacity, prescribe training, and assess the effects of training. The human literature identified approximately twenty-five methods to predict the MLSS. This communication compares the concordance between the two D methods and the MLSS. Under laboratory conditions, ten teaching horses underwent a submaximal graded exercise test (GXT) on a treadmill to obtain their lactate-velocity curves (LVC). They performed three to five 30-min continuous running sess...
St George L, Nankervis K, Walker V, Maddock C, Robinson A, Sinclair J, Hobbs SJ.Despite growing evidence on the adaptive movement patterns that horses adopt during water treadmill (WT) exercise, underlying adaptations in muscle activity remain uninvestigated. This feasibility study aimed to develop a method for the synchronous measurement of muscle activity and movement of horses during WT exercise. Combined surface electromyography (sEMG) (2000 Hz) from selected hindlimb (biceps femoris, gluteus medius, tensor fasciae latae) and epaxial (longissimus dorsi) muscles, and three-dimensional kinematic (200 Hz) data from the back and pelvis of one (n = 1) horse were collected ...
Hammack SM, Moshage SG, Kersh ME, McCoy AM.To quantify circulating levels of myokines with a known role in bone remodeling (receptor activator of nuclear factor κ B ligand [RANK-L], matrix metalloproteinase 2 [MMP-2], and irisin) in foals in response to exercise and over the first year of life. Unassigned: 12 foals were enrolled in the study; 6 underwent an 8-week exercise program, and 6 were nonexercised controls. Blood samples were collected between 2 and 11 months of age. Receptor activator of nuclear factor κ B ligand, MMP-2, and irisin were quantified using equine-specific ELISAs. Unassigned: RANK-L, MMP-2, and irisin did not ch...
Sande A, Santosuosso E, Scharf JE, Shoemaker SJ, Temple S, Hemmerling K, Kell T, Leguillette R, Bayly WM.To compare maximal lactate steady-state (MLSS) speeds determined using a treadmill-dependent invasive reference method (RM) with 2 noninvasive methods based on heart rate variability-focused analysis of exercise ECGs. Unassigned: This was a randomized, blinded study using 7 fit Thoroughbreds. A standardized incremental exercise treadmill test (SET) where blood lactate concentration ([La]) was measured after every step facilitated calculation of speeds at which [La] was 1.5, 2.0, and 2.5 mmol/L. The RM required steady-state exercise (SS) at each of these speeds for 25 minutes or until [La] incr...
Jeong S, Bond S, Bayly W, Sole-Guitart A.To quantify the impact of experimentally induced dorsal nasopharyngeal collapse (NPC) on respiratory performance parameters and assess the efficacy of laser fenestration of the dorsal pharyngeal recess as a treatment option for experimentally induced NPC. Methods: Experimental interventional study. Methods: Six adult Standardbreds (one with naturally occurring disease). Methods: After an 8 week conditioning program, baseline parameters (V̇Omax, pharyngeal pressure, peak airflows, upper airway resistance) and dynamic endoscopy videos were collected in a high-speed treadmill test (T1). Dorsal N...
Söderroos D, Stefánsdóttir GJ, Ragnarsson S, Gunnarsson V, Jansson A.Weight-carrying capacity is important in riding horses both for performance and welfare, yet there is no standardized method to estimate individual horses' weight-carrying capacity. This study investigated the correlation between the physiological response during a (i) standardized incremental exercise test (SET) on a treadmill and a (ii) ridden incremental weight-carrying exercise test (WET). Sixteen horses (15 ± 3 years) performed both tests, including four steps with increased speed or weight load, respectively. Body weight ratio (BWR) in the WET was 20%, 25%, 30%, and 35% in each st...
Frontiers in geneticsOctober 1, 2025
Volume 16 1676558 doi: 10.3389/fgene.2025.1676558
Ma S, Ren W, Li Z, Li L, Wang R, Su Y, Huang Q, Dehaxi S, Wang J.Equine athletic performance is modulated by both genetic and epigenetic mechanisms. As dynamic regulators of gene expression, MicroRNAs (miRNAs) play a central role in the physiological response to exercise-induced stress18. This study focused on the top three elite Yili horses from a 5000-m race, collecting peripheral blood samples pre-race (group B) and post-race (group A). A longitudinal comparative analysis integrating miRNA omics profiling and target gene functional enrichment was performed. Nineteen miRNAs exhibited significant differential expression (10 upregulated, 9 downregulated), w...
Marlin D, Randell O, Mayhew E, Blake R.The aim of this study was to investigate the effect of girth design and girth tension; six horses regularly ridden were used. Each horse underwent four experimental sessions in an unbalanced Latin-square design with two girth tensions (8 kg or 16 kg) and two girth designs (straight girth (S) or anatomical girth (A)). Pressure between the saddle and the horse was measured at 100 Hz with a pressure mat (0.5 sensels per cm). Notably, 2D limb kinematics were determined from anatomical markers placed on the fore and hindlimbs. Video was collected at 240 fps. There was no significant effect of girth...
Tranquille C, Nankervis K, Tacey J, Hopkins E, Deckers I, Walker V, MacKechnie-Guire R, Newton R, Murray R.Water treadmill (WT) exercise has become a popular tool for equine training and rehabilitation. However, few studies describe the long-term effects of WT exercise in low water on muscle development (MD). This study's objectives were to compare MD changes over a 40-week period in sport horses that regularly used WT in low water within training (Group WTH, = 55) and a control group that did not (control, = 28). Subjective MD assessments were undertaken using an adaptation of a previously published method at weeks 0, 20 and 40. For Group WTH, MD significantly increased in the neck, pelvis and h...
Sikorska U, Maśko M, Rey B, Domino M.Water treadmill (WT) exercise is used for horses' rehabilitation and training. Given that each training needs to be individualized for each horse, the goal is to assess whether infrared thermography (IRT) can serve as a non-invasive tool for daily monitoring of individual training and rehabilitation progress in horses undergoing WT exercise. Fifteen Polish Warmblood school horses were subjected to five WT sessions: dry treadmill, fetlock-depth water, fetlock-depth water with artificial river (AR), carpal-depth water, and carpal-depth water with AR. IRT images, collected pre- and post-exercise,...
Geiger T, Lindenhahn L, Delarocque J, Geburek F.Data about efficacy of different training modalities during rehabilitation of horses with back pain is scarce. The aim of this study was to analyze the effect of water treadmill training, lunging and dry treadmill training in horses with back pain. Methods: Eighteen warmblood riding horses referred with confirmed clinical signs of back pain including abnormal responses to passive mobilisation were randomized into three groups to participate in a 6-week water treadmill training, lunging or dry treadmill program under otherwise identical conditions. Two clinicians, one blinded to the program, pe...
Vermedal H, Hellings IR, Fretheim-Kelly ZL, Fintl C, Olsen HMB, Strand E.Exercise-related upper respiratory tract (URT) disorders are common in racehorses. Objective assessment of URT mechanics is essential to quantify degrees of obstruction caused by URT disorders identified upon dynamic endoscopy. Objective: To establish reference values for inspiratory and expiratory tracheal pressures (cmHO) during high-speed treadmill endoscopy in harness racehorses with clinically normal URTs. Methods: Prospective observational study. Methods: Tracheal pressures were measured in harness racehorses (Standardbreds and Norwegian-Swedish coldblooded trotters) in which no URT abno...
Strand E, Vermedal H, Olsen HMB, Fjordbakk CT, Fretheim-Kelly ZL.Clinical evaluation of alar fold (AF) collapse is presently based upon subjective evaluation of improvement in breathing and respiratory noise after suturing the AFs dorsally. Objective: To evaluate use of nasopharyngeal airway pressure (NAP) as an objective method of assessing for the presence of AF collapse during exercise. NAPs should also potentially provide a precise means to grade the degree of airway obstruction present and response to surgical treatment. Methods: Prospective clinical study of actively racing Standardbred horses. Methods: Standardbreds undergoing this test were outfitte...
Sales NAA, Carvalho JRG, Littiere TO, Costa GB, Silva ACY, Rodriguez IDM, Castro CM, Anjos LS, Ottati ACM, Alcaide JA, Ramos GV, Ferraudo AS....Whole-body vibration (WBV) has the potential to enhance post-exercise recovery in humans. Heart rate variability (HRV), a well-established biomarker of cardiac autonomic regulation (CAR), provides insight into autonomic reactivity during recovery from exercise. Objective: To investigate CAR in healthy horses during post-exercise recovery following an acute intensive exercise bout (AIEB) with WBV intervention. Methods: A single AIEB was prescribed at velocities corresponding to lactate threshold (VLT), and the eight horses performed on treadmill with 5 % slope, 2 min at 110 % VLT followed by 3 ...
Li C, Li X, Liu K, Xu J, Yu J, Liu Z, Mach N, Ni W, Liu C, Zhou P, Wang L, Hu S.Gut microbes play a vital role in host physiology, but whether specific bacterial functions contribute to the exceptional athletic performance of racehorses needs to be better understood. Here, we identify an association of gut butyrate-producing bacteria with athletic performance in racehorses (Thoroughbred horse). Butyrate-producing bacteria and microbial butyrate synthesis genes were significantly enriched in the racehorse gut, and the GC-MS results confirmed this conclusion. Using a mouse model, we demonstrated that sodium butyrate is sufficient to increase treadmill run time performance. ...
Domino M, Borowska M, Stefanik E, Domańska-Kruppa N, Skibniewski M, Turek B.In equine surface electromyography (sEMG), challenges related to the reliability and interpretability of data arise, among other factors, from methodological differences, including signal processing and analysis. The aim of this study is to demonstrate the filtering-induced changes in basic signal features in relation to the balance between signal loss and noise attenuation. Raw sEMG signals were collected from the quadriceps muscle of six horses during walk, trot, and canter and then filtered using eight filtering methods with varying cut-off frequencies (low-pass at 10 Hz, high-pass at 20 Hz...
Ohmura H, Ebisuda Y, Takahashi Y, Mukai K.Pre-exercise cooling may prevent exertional heat illness in horses. We hypothesized that pre-exercise cooling before warm-up in a hot environment would not affect performance but would mitigate reductions in body weight and increases in body temperature following exercise. Six trained Thoroughbred horses were studied using a randomized, crossover design with three pre-treatments: 30-min walk on a treadmill at 1.7 m/sec (WALK), 30 min of standing (REST), and a 10-min pre-cooling shower at 26.2 ± 0.8°C (SHOWER). All horses underwent each pre-treatment, followed by a warm-up and main exercise i...
Carvalho JRG, Sales NAA, Littiere TO, Costa GB, Castro CM, Polisel EEC, Orsi JB, Ramos GV, Santos IFC, Gobatto CA, Manchado-Gobatto FB, Ferraz GC.Several studies have explored alternatives to enhance the performance, health, and safety of sports horses. One promising method involves the use of vibrating platforms (VP), which offer passive exercise stimulation via mechanical oscillations distributed throughout the body. This type of exercise is referred to as whole-body vibration (WBV) and is an emerging strategy for accelerating muscle recovery. This study examined the dynamics of proteins responsible for transporting monocarboxylates (MCT1 and MCT4), and their relationship with lactatemia and acid-base balance in connection with WBV re...
Littiere TO, Costa GB, Sales NAA, Carvalho JRG, Rodrigues IDM, Ramos GV, Ferraz GC.In humans, there is an ongoing academic discussion about measuring plasma lactate concentration ([La]) during an incremental exercise test (IET) to establish thresholds that can predict the maximal lactate steady state (MLSS). Training studies on horses have utilized the onset of [La] (OBLA), also known as V, the velocity at which the [La] of 4 mM is reached. This study assesses the effectiveness of four methods for estimating the MLSS in teaching horses. Ten teaching horses underwent a single IET to determine four exercise intensity thresholds for predicting MLSS and performed several constan...
Stucchi L, Rossi R, Mainardi E, Ferrucci F.Endurance is an equestrian discipline that primarily relies on aerobic metabolism. Intense aerobic exercise produces reactive oxygen species due to an imbalance between oxidant and antioxidant substances, known as oxidative stress, which may reduce athletic performance. This study evaluated the effects of a feed supplement containing natural antioxidants and omega-3 fatty acids on the blood antioxidant activity and the athletic condition of endurance horses undergoing an exercise test. Twelve Arabian endurance horses were randomly assigned to treatment or control groups. At T0, blood lactate, ...
Davis MS, Bayly WM, Hansen CM, Barrett MR, Blake CA.The intracellular environment of skeletal muscle can develop pronounced hyperthermia and acidosis during strenuous exercise, and these alterations in the typical intracellular conditions have been shown to alter mitochondrial respiration. However, the impact of these conditions on ATP synthesis is poorly understood. We used Thoroughbred racehorses to test the hypothesis that both hyperthermia and acidosis decrease the rate of ATP synthesis, but that athletic conditioning mitigates this loss of phosphorylation capacity. Isolated mitochondria were harvested from skeletal muscle before and after ...
Vasseur M, Lepers R, Langevin N, Julliand S, Grimm P.This pilot study sought to explore the contribution of the large intestine microbiota to energy metabolism and exercise performance through its ability to degrade fibers into short-chain fatty acids (SCFAs). To investigate this, a correlational study was carried out on athlete horses under the same management conditions. Fecal microbiota diversity and composition, fibrolytic efficiency and SCFAs were analyzed. An incremental running test was carried out to estimate the maximal running speed (MRS) of the horses, and blood samples were taken to measure energy metabolism parameters. MRS was posit...
Heglund NC, Taylor CR.In this study we investigate how speed and stride frequency change with body size. We use this information to define 'equivalent speeds' for animals of different size and to explore the factors underlying the six-fold difference in mass-specific energy cost of locomotion between mouse- and horse-sized animals at these speeds. Speeds and stride frequencies within a trot and a gallop were measured on a treadmill in 16 species of wild and domestic quadrupeds, ranging in body size from 30 g mice to 200 kg horses. We found that the minimum, preferred and maximum sustained speeds within a trot and a...
McIlwraith CW, Frisbie DD, Rodkey WG, Kisiday JD, Werpy NM, Kawcak CE, Steadman JR.This study evaluated intra-articular injection of bone marrow-derived mesenchymal stem cells (BMSCs) to augment healing with microfracture compared with microfracture alone. Methods: Ten horses (aged 2.5 to 5 years) had 1-cm2 defects arthroscopically created on both medial femoral condyles of the stifle joint (analogous to the human knee). Defects were debrided to subchondral bone followed by microfracture. One month later, 1 randomly selected medial femorotibial joint in each horse received an intra-articular injection of either 20 × 10(6) BMSCs with 22 mg of hyaluronan or 22 mg of hyalurona...
Rubin CT, Lanyon LE.Rosette strain gauges were attached to the midshaft of the radius and tibia of two horses and two dogs, which ran on a treadmill through their entire range of speed and gait. The relative magnitudes of the principal strains on the opposite cortices of each bone remained constant through the stance phase of the stride, and their orientation varied by a maximum of only 14 degrees through the entire speed range. The maximum strain rate increased linearly with speed, but the peak strain magnitude was also dependent upon the gait used, increasing incrementally by up to 59% at the transition from wa...
Pfau T, Witte TH, Wilson AM.Biomechanical studies often employ optical motion capture systems for the determination of the position of an object in a room-based coordinate system. This is not ideal for many types of study in locomotion since only a few strides may be collected per ;trial', and outdoor experiments are difficult with some systems. Here, we report and evaluate a novel approach that enables the user to determine linear displacements of a proprietary orientation sensor during cyclical movement. This makes experiments outside the constraints of the laboratory possible, for example to measure mechanical energy ...
Minetti AE, ArdigO LP, Reinach E, Saibene F.Three-dimensional motion capture and metabolic assessment were performed on four standardbred horses while walking, trotting and galloping on a motorized treadmill at different speeds. The mechanical work was partitioned into the internal work (W(INT)), due to the speed changes of body segments with respect to the body centre of mass, and the external work (W(EXT)), due to the position and speed changes of the body centre of mass with respect to the environment. The estimated total mechanical work (W(TOT)=W(INT)+W(EXT)) increased with speed, while metabolic work (C) remained rather constant. A...
Rhodin M, Persson-Sjodin E, Egenvall A, Serra Bragança FM, Pfau T, Roepstorff L, Weishaupt MA, Thomsen MH, van Weeren PR, Hernlund E.The main criteria for lameness assessment in horses are head movement for forelimb lameness and pelvic movement for hindlimb lameness. However, compensatory head nod in horses with primary hindlimb lameness is a well-known phenomenon. This compensatory head nod movement can be easily misinterpreted as a sign of primary ipsilateral forelimb lameness. Therefore, discriminating compensatory asymmetries from primary directly pain-related movement asymmetries is a prerequisite for successful lameness assessment. Objective: To investigate the association between head, withers and pelvis movement asy...
Minetti AE.By refining a previously published model, a simple equation for the estimation of the mechanical internal work during locomotion is presented. The only input variables are the progression speed, the stride frequency and the duty factor, i.e. the fraction of the stride duration at which a foot is in contact with the ground. The inclusion of this last variable, easily measurable, allows to obtain a single equation for both walking and running. The model predictions have been compared with the mechanical internal work experimentally obtained on humans in several conditions: speeds (range 0.8-3.3 ...
Weishaupt MA, Wiestner T, Hogg HP, Jordan P, Auer JA.The study was performed to obtain a detailed insight into the load and time shifting mechanisms of horses with unilateral weight-bearing forelimb lameness. Reversible lameness was induced in 11 clinically sound horses by applying a solar pressure model. Three degrees of lameness (subtle, mild and moderate) were induced and compared with sound control measurements. Vertical ground reaction force-time histories of all four limbs were recorded simultaneously on an instrumented treadmill. Four compensatory mechanisms could be identified that served to reduce structural stress, i.e. peak vertical f...
Buchner HH, Savelberg HH, Schamhardt HC, Merkens HW, Barneveld A.A kinematic analysis was carried out to compare treadmill and overground locomotion in horses at the trot. Stride variables and limb and trunk movements of 10 Dutch Warmblood horses were measured using the CODA-3 gait analysis system. Overground recordings were made on a rubber ground surface and on an asphalt track. Treadmill recordings were taken after a controlled habituation programme and at the same velocities as measured overground. On asphalt, a shorthened stride duration and a decreased vertical displacement of the withers were found compared with those on rubber ground. On the treadmi...
Wagner PD, Gillespie JR, Landgren GL, Fedde MR, Jones BW, DeBowes RM, Pieschl RL, Erickson HH.Arterial hypoxemia has been reported in horses during heavy exercise, but its mechanism has not been determined. With the use of the multiple inert gas elimination technique, we studied five horses, each on two separate occasions, to determine the physiological basis of the hypoxemia that developed during horizontal treadmill exercise at speeds of 4, 10, 12, and 13-14 m/s. Mean, blood temperature-corrected, arterial PO2 fell from 89.4 Torr at rest to 80.7 and 72.1 Torr at 12 and 13-14 m/s, respectively, whereas corresponding PaCO2 values were 40.3, 40.3, and 39.2 Torr. Alveolar-arterial PO2 di...
Robert C, Valette JP, Pourcelot P, Audigié F, Denoix JM.A thorough knowledge of the horse's back and limb movements at different speeds is important in the design of training programmes and the prevention of speed-related injuries. The objective of this study was to investigate changes in muscle activity and kinematics of the trot with increased speed. To evaluate these effects, 4 Saddlehorses were recorded while trotting on a horizontal treadmill at speeds ranging from 3.5-6.0 m/s. The 3-D trajectories of skin markers on the left side of the horse and the dorsal midline of the trunk were established. Electrical activity was obtained simultaneously...
Jones JH, Longworth KE, Lindholm A, Conley KE, Karas RH, Kayar SR, Taylor CR.This study investigated mechanisms used by horses and steers to increase O2 uptake and delivery (VO2) from resting to maximal rates and identified the mechanisms that enable horses to achieve higher maximal rates of O2 consumption (VO2max) than steers. VO2 and circulatory variables were measured while Standardbred trotting horses and steers (450-kg body mass) stood quietly and ran on a treadmill at speeds up to those eliciting VO2max. As VO2 increased in both species, heart rate and circulating hemoglobin (Hb) concentration increased, thereby increasing O2 delivery by the circulation, while ca...
Keegan KG, Yonezawa Y, Pai PF, Wilson DA, Kramer J.To compare a sensor-based accelerometer-gyroscopic (A-G) system with a video-based motion analysis system (VMAS) technique for detection and quantification of lameness in horses. Methods: 8 adult horses. Methods: 2 horses were evaluated once, 2 had navicular disease and were evaluated before and after nerve blocks, and 4 had 2 levels of shoe-induced lameness, alternatively, in each of 4 limbs. Horses were instrumented with an accelerometer transducer on the head and pelvis, a gyroscopic transducer on the right forelimb and hind feet, and a receiver-transmitter. Signals from the A-G system were...
Martin BB, Reef VB, Parente EJ, Sage AD.To determine results for horses undergoing a high-speed treadmill examination, including videoendoscopy of the pharynx and larynx before and during exercise, echocardiography before and after exercise, and electrocardiography before, during, and after exercise, because of poor performance. Methods: Retrospective study. Methods: 348 horses. Results: A definitive diagnosis was obtained for 256 (73.5%) horses. One hundred forty-eight horses had dynamic obstruction of the airway during exercise, 33 had clinically important cardiac arrhythmias alone, 22 had a combination of dynamic airway obstructi...
McGivney BA, Eivers SS, MacHugh DE, MacLeod JN, O'Gorman GM, Park SD, Katz LM, Hill EW.Selection for exercise-adapted phenotypes in the Thoroughbred racehorse has provided a valuable model system to understand molecular responses to exercise in skeletal muscle. Exercise stimulates immediate early molecular responses as well as delayed responses during recovery, resulting in a return to homeostasis and enabling long term adaptation. Global mRNA expression during the immediate-response period has not previously been reported in skeletal muscle following exercise in any species. Also, global gene expression changes in equine skeletal muscle following exercise have not been reported...
Kawcak CE, Frisbie DD, Werpy NM, Park RD, McIlwraith CW.To identify changes in imaging outcomes in a controlled model of osteoarthritis (OA) vs exercise. Methods: Sixteen 2-year-old horses were randomly assigned to an exercise control (n=8) or an exercise OA (n=8) group. All horses had middle carpal joints arthroscopically explored and an osteochondral fragment was induced in one middle carpal joint of the OA group. All horses were treadmill exercised for the duration of the study (91 days). Clinical, radiographic, nuclear scintigraphic, computed tomographic and magnetic resonance imaging (MRI) examinations were performed and outcomes of these were...
Physick-Sheard PW, Marlin DJ, Thornhill R, Schroter RC.The pattern of variation in heart rate on a beat-to-beat basis contains information concerning sympathetic (SNS) and parasympathetic (PNS) contributions to autonomic nervous system (ANS) modulation of heart rate (HR). In the present study, heart period (RR interval) time series data were collected at rest and during 3 different treadmill exercise protocols from 6 Thoroughbred horses. Frequency and spectral power were determined in 3 frequency bands: very low (VLF) 0-0.01-0.07-< or = 0.5 cycles/beat. Indicators of sympathetic (SNSI = LO/HI) and parasympathetic (PNSI = HI/TOTAL) activity were...
Hoyt DF, Wickler SJ, Cogger EA.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...
Fedak MA, Heglund NC, Taylor CR.This is the second paper in a series examining the link between energetics and mechanics of terrestrial locomotion. In this paper, the changes in the kinetic energy of the limbs and body relative to the centre of mass of an animal (EKE, tot) are measured as functions of speed and body size. High-speed films (light or X-ray) of four species of quadrupeds and four species of bipeds running on a treadmill were analysed to determine EKE, tot. A mass-specific power term, EKE, tot/Mb was calculated by adding all of the increments in EKE during an integral number of strides and dividing by the time i...
Weishaupt MA, Wiestner T, Hogg HP, Jordan P, Auer JA.The compensatory mechanisms of horses with weightbearing hindlimb lameness are still not fully understood. Objective: That weightbearing, unilateral hindlimb lameness would not only alter stride characteristics to diminish structural stress in the affected limb but also induce compensatory load adjustments in the other supporting limbs. Objective: To document the load and time shifting mechanisms of horses with unilateral weightbearing hindlimb lameness. Methods: Reversible lameness was induced in 8 clinically sound horses by applying a solar pressure model. Three degrees of lameness (subtle, ...
Griffin TM, Kram R, Wickler SJ, Hoyt DF.We studied nine adult horses spanning an eightfold range in body mass (M(b)) (90-720 kg) and a twofold range in leg length (L) (0.7-1.4 m). We measured the horses' walk-trot transition speeds using step-wise speed increments as they locomoted on a motorized treadmill. We then measured their rates of oxygen consumption over a wide range of walking and trotting speeds. We interpreted the transition speed results using a simple inverted-pendulum model of walking in which gravity provides the centripetal force necessary to keep the leg in contact with the ground. By studying a large size range of ...
Manohar M.Using radionuclide-labelled microspheres, 15 micron in diameter, we studied blood flow in the respiratory muscles (diaphragm and intercostal muscles), abdominal organs (adrenal glands, kidneys, pancreas, spleen and the small and large intestines), muscles of propulsion (gluteus medius and biceps femoris), and other working (triceps brachii and longissimus dorsi lumborum) and non-working (temporal and masseter) muscles of ponies at rest and during maximal exercise performed on a treadmill. During maximal exercise heart rate, whole body O2 consumption, cardiac output and mean aortic pressure inc...
Licka T, Frey A, Peham C.The pattern of electromyographic activity of the equine long back muscle at the walk has not yet been reported. The aim of this study was to use surface electromyography to measure activity of the longissimus dorsi muscles of horses walking on a treadmill. Fifteen horses without back pain were used and electromyographs were recorded bilaterally from the longissimus dorsi muscles at the level of T12, T16 and L3. Mean electromyograph activity and mean motion were calculated for each horse. At the walk, only one maximum activity for each longissimus dorsi muscle was detected during each motion cy...
Couëtil LL, Denicola DB.The purpose of this study was to evaluate the relationship between bronchoalveolar lavage (BAL) cytology, arterial blood gases and plasma lactate concentration during a standardised treadmill test (STT) in racehorses with small-airway inflammation (SAI), or exercise-induced pulmonary haemorrhage (EIPH). Sixteen Thoroughbred and 20 Standardbred actively racing racehorses, were divided into a control group (n = 10), EIPH group (n = 13) and SAI group (n = 13). Each STT consisted of a 2 min trot at 4 m/s followed by 5 x 1 min, incremental speed steps (6, 8, 10, 11 and 12 m/s) at 10% incline for Th...
Keegan KG, Wilson DA, Wilson DJ, Smith B, Gaughan EM, Pleasant RS, Lillich JD, Kramer J, Howard RD, Bacon-Miller C, Davis EG, May KA, Cheramie HS....To estimate sensitivity and accuracy of subjective evaluation of mild lameness in horses during treadmill locomotion and to correlate subjective evaluation with kinematic analysis. Methods: 19 lame and 5 clinically normal horses. Methods: Lameness was evaluated by subjective score and kinematic analysis before and after palmar digital nerve block (PDNB). Evaluations were made by 6 clinicians and 7 interns or residents. Within- and between-observer agreement analyses (kappa values) were calculated and compared, using a Student's t-test. Pearson's product-moment correlation coefficients were cal...
Faber M, Johnston C, Schamhardt H, van Weeren R, Roepstorff L, Barneveld A.To determine movements of the vertebral column of horses during normal locomotion. Methods: 5 young Dutch Warmblood horses that did not have signs of back problems or lameness. Methods: Kinematics of 8 vertebrae (T6, T10, T13, T17, L1, L3, L5, and S3) and both tuber coxae were determined, using bone-fixated markers. Measurements were recorded when the horses were trotting on a treadmill at a constant speed of 4.0 m/s. Results: Flexion-extension and axial rotation were characterized by a double sinusoidal pattern of motion during 1 stride cycle, whereas lateral bending was characterized by 1 pe...
Faber M, Schamhardt H, van Weeren R, Johnston C, Roepstorff L, Barneveld A.To determine kinematic movements of the vertebral column of horses during normal locomotion. Methods: 5 Dutch Warmblood horses without apparent lameness or problems associated with the vertebral column. Methods: Kinematics of 8 vertebrae (T6, T10, T13, T17, L1, L3, L5, and S3) and both tuber coxae were determined, using bone-fixated markers. Horses were recorded while walking on a treadmill at a constant speed of 1.6 m/s. Results: Flexion-extension was characterized by 2 periods of extension and flexion during 1 stride cycle, whereas lateral bending and axial rotation were characterized by 1 p...
Rhodin M, Gómez Alvarez CB, Byström A, Johnston C, van Weeren PR, Roepstorff L, Weishaupt MA.Dressage involves training of the horse with the head and neck placed in a position defined by the rider. The best position for dressage training is currently under debate among riders and trainers, but there are few scientific data available to confirm or disprove the different views. Objective: To evaluate the kinematic effects of different head and neck positions (HNPs) in elite dressage horses ridden at trot. Methods: Seven high-level dressage horses were subjected to kinetic and kinematic measurements when ridden on a treadmill with the head and neck in 5 different positions. Results: Com...
Birch HL, McLaughlin L, Smith RK, Goodship AE.The equine superficial digital flexor tendon (SDFT) functions as an energy store during high-speed gaits reducing the energetic cost of locomotion. To enable the SDFT to function effectively, the appropriate mechanical properties are essential. We tested the hypothesis that the SDFT does not undergo gross hypertrophy in response to high-intensity exercise whereas tendons not involved in energy storage undergo adaptive hypertrophy. Two groups (n = 6) of Thoroughbred fillies were trained at high-intensity on a high-speed equine treadmill for 5 months (short-term study) or 18 months (long-term st...
Lorenzo-Figueras M, Merritt AM.To assess effects of exercise on a treadmill with changes in gastric volume and pH in the proximal portion of the stomach of horses. Methods: 3 healthy adult horses. Methods: A polyester bag of approximately 1,600 mL was placed into the proximal portion of the stomach of each horse via a nasogastric tube. Changes in bag volume, determined by an electronic barostat, were recorded before, during, and after a training session on a treadmill with and without prior withholding of food. In separate experiments, pH in the proximal portion of the stomach was continuously recorded during exercise for f...
