Exercise tests are assessments used to evaluate the cardiovascular and respiratory function of horses during physical activity. These tests help in determining the fitness level, performance capacity, and potential health issues in equine athletes. Parameters such as heart rate, respiratory rate, blood lactate levels, and oxygen consumption are typically measured during these tests. Variations in these parameters can indicate the horse's adaptation to training or uncover underlying medical conditions. This page compiles peer-reviewed research studies and scholarly articles that explore the methodologies, applications, and implications of exercise tests in equine sports medicine and veterinary practice.
Evans DL, Rose RJ.Six Standardbred horses were used to evaluate the time course of pulmonary gas exchange, ventilation, heart rate (HR) and acid base balance during different intensities of constant-load treadmill exercise. Horses were exercised at approximately 50%, 75% and 100% maximum oxygen uptake (VO2 max) for 5 min and measurements taken every 30 s throughout exercise. At all work rates, the minute ventilation, respiratory frequency and tidal volume reached steady state values by 60 s of exercise. At 100% VO2 max, the oxygen consumption (VO2) increased to mean values of approximately 130 ml/kg.min, which ...
Weber JM, Dobson GP, Parkhouse WS, Wheeldon D, Harman JC, Snow DH, Hochachka PW.This study characterizes the effects of exercise on the cardiac output (Q) and the metabolic rate (VO2) of trained Thoroughbred racehorses. Heart rate, Q, and arteriovenous (a-v)O2 difference were measured at rest and at three levels of submaximal treadmill exercise (1.6 m/s walk and 3-4 m/s trot at 6% incline, and 6.5 m/s horizontal canter). Heart rate and (a-v)O2 difference were also measured during maximal exercise (12.5 m/s gallop, 5% incline) to obtain an estimate of maximum O2 uptake (VO2max). The walk, trot, and canter represented 25, 45, and 55% VO2max. Mean heart rate went from 48.9 (...
De Waal A, Littlejohn A, Potgieter GM, Van der Berg J, Minnaar PI, Smith A.An apparatus was designed to collect four consecutive blood samples from exercising horses. The collection of each sample was controlled by valves activated by radiotelemetry signals transmitted by an observer. Using the device, venous blood samples were collected from ten thoroughbred racehorses before, during and after a 400 m training gallop. Blood glucose increased markedly post-exercise. Both phosphorus and potassium concentrations increased during exercise, decreased post-exercise and recovered to pre-exercise levels within 120 minutes. The system was modified to collect anaerobic sample...
Thornton JR.In the athletic horse, an exercise test may be required to measure the adaptation of the animal to a specific training program; to modify the training program in response to the progress achieved; to investigate the reasons for failure to perform at the expected level; and to form part of an overall clinical examination of a horse with a specific disability. This article includes information on the scope and form of an exercise test, the parameters measured during the test and their interpretation, treadmill and track tests, and the clinical applications of exercise tests.
Parks CM, Manohar M.In recent years, increasing attention has been focused on the physiological responses of the horse to maximal exercise. Cardiovascular response in near maximally exercised galloping ponies (heart rate 225 +/- 7 beats/min; whole body oxygen consumption 122 +/- 12 ml/min/kg) comprised a marked increase in blood flow to the cerebellum, myocardium, diaphragm and the working muscles, while renal blood flow decreased precipitously. Cerebral and brainstem perfusion did not vary from resting values. Transmural homogeneity of myocardial blood flow persisted during near maximal exercise. It was reported...
Rose RJ, Allen JR, Brock KA, Clark CR, Hodgson DR, Stewart JH.Five standardbred geldings received intravenous clenbuterol hydrochloride and saline in a crossover experiment to evaluate the effects of clenbuterol on certain cardiorespiratory parameters during and after treadmill exercise. The exercise test consisted of four steps. Step 1 at a speed of 76 m per minute, step 2 at 129 m per minute, step 3 at 190 m per minute and step 4 at 236 m per minute. The duration of each step was two minutes, except step 4 which was four minutes. The treadmill was set at a grade of 19 per cent. Before exercise, 30 minutes after clenbuterol or saline administration, art...
Westerling D.Thirteen experienced riders and three elite riders underwent bicycle ergometer tests at submaximal and maximal workloads. Oxygen uptake, pulmonary ventilation and heart rate were also studied during riding at a walk, a trot and a canter. The mean maximal oxygen uptake of the experienced riders in the ergometer test (2.71 . min-1) was superior to the average maximal oxygen uptake of other groups of the same age and sex. The average oxygen uptake of the experienced riders in trot sitting was 1.701 . min-1, trot rising 1.681 . min-1 and in canter 1.801 . min-1. The experienced riders used at leas...
Nicholl TK, Fregin GF, Gerber NH.The literature on exercise physiology in the horse with special reference to swimming is briefly reviewed. The use of a pool for swimming horses is described and a technique discussed for the collection of haematologic and haemodynamic data using this form of exercise.
Maier-Bock H, Ehrlein HJ.During a gradually increasing exercise test heart rates were determined in healthy animals and in 2 groups of sick horse. These included 31 animals with a chronic pulmonary disorder and 5 with chronic heart disease. The alteration in heart rate was correlated with the clinical signs exhibited. In the horses with lung disease there was a close correlation between the stage of the diseases and the heart rate during the exercise test. In 3 animals with heart valve disease there was no apparent difference in heart rate compared with healthy horses. On the other hand the exercising heart rate of ho...
Kohn CW, Muir WW, Sams R.Plasma volume and extracellular fluid volume were determined in horses at rest and immediately after a standardized exercise test. Exercising during training demonstrated no detectable effect on plasma or extracellular fluid volume determinations when compared with resting values. An explanation of this finding and an argument for the proper analysis of plasma and extravascular fluid volumes are presented.
Skarda RT, Muir WW, Milne DW, Gabel AA.Five healthy, mature, previously trained Standardbred horses were given no exercise (left in a stall) for 4 months, then jogged (slow exercise) for 3 weeks, and placed in a 6-week training period. Cardiac variables were measured at the beginning of training and after 14, 20, 35, and 42 days of training before and at 10, 15, 20, 25, and 30 minutes after a 1.8-km (in 3:12 +/- 2 seconds) standard, submaximal exercise test on a deep 0.53-km track. There was no significant change during the 6-week conditioning period in the following variables at rest or at any of the times observed during recovery...
Buntenkötter S, Deegen E.Cardioversion through varying quinidine sulphate treatments was achieved in 3 riding horses with auricular fibrillation. The horses were subjected to continual telemetric ECG registration before and after reversion in a uniform exercise-tolerance-test. A comparison of the heart rate curves showed a strong decline of the heart beat frequency during the exercise phase after synchronisation. The decrease in heart rate during exercise was greater than 30% in all 3 patients. Anti-arrhythmic treatment is, therefore, recommended for horses with auricular fibrillation and without concurrent heart dise...
Brown DG.Physiologic responses of irradiated and nonirradiated Shetland Ponies to controlled exercise were measured over a period of 5 years. The 5-year test began when the ponies were 3 years old and 5 months after they were exposed to 650 R of 60-Co gamma radiation. Significant differences in heart rates, respiratory rates, and rectal temperatures were demonstrated between irradiated and nonirradiated ponies when subjected to exercise and high ambient temperatures. Inthe irradiated group, heart rates were usually slower, especially during recovery immediately after exercise, and respiratory rates and...
Davies HM.The third metacarpal bones (MC3) of racing Thoroughbreds are a common site for bone damage. The midshaft dorsal cortex (DC) of MC3 thickens in response to fast exercise. It is not clear if it changes to a shape and size that limits the peak bone strains to a range associated with normal loading in other species. Objective: To relate the proportionate size of the DC cortex in racehorses exercising at racing speed to surface strains, and test whether the DC reached a plateau that was sustained through subsequent exposures to racing speed exercise. Methods: Standardised lateral MC3 radiographs we...
Martin A, Lepers R, Vasseur M, Julliand S.Large amounts of high-starch concentrates are traditionally fed to horses in training. However, this has been associated with digestive or muscle diseases and behavioural modifications. In parallel, it has been demonstrated that horses fed high-fibre, low-starch diets achieve the same performance over an exercise test as the ones fed high-starch diets. However, whether the same performance level can be maintained over a longer training cycle is still being determined. This study aimed to compare the evolution in physical performance and cardiorespiratory responses of two groups of French Trott...
Gregg SR, Barshick MR, Johnson SE.Following strenuous exercise, skeletal muscle experiences an acute inflammatory state that initiates the repair process. Systemic hyaluronic acid (HA) is injected to horses routinely as a joint anti-inflammatory. To gain insight into the effects of HA on skeletal muscle, adult Thoroughbred geldings (n = 6) were injected with a commercial HA product weekly for 3 weeks prior to performing a submaximal exercise test. Gluteal muscle (GM) biopsies were obtained before and 1 h after exercise for gene expression analysis and HA localization. The results from RNA sequencing demonstrate differences in ...
Massie SL, Léguillette R.Barrel racing involves sprinting through a cloverleaf pattern in under 20 s. The prevalence of upper airway obstructions (UAO) in barrel racers is unknown, thus a retrospective analysis of 164 client-owned horses referred for overground endoscopy (OGE) between 2014 and 2022 was performed. Referring complaints included respiratory noise, cough, epistaxis, behaviour (owner reported stress/anxiety, refusal to enter arena, excessive head shaking), and/or poor performance. Horses performed a standardized exercise test with low and high-speed components. Videoendoscopic recordings were systematical...
Ramos GV, Titotto AC, da Costa GB, Ferraz GC, de Lacerda-Neto JC.The maximal lactate steady state (MLSS) is a well-known gold standard method for determining the aerobic capacity of athletic horses. Owing to its high cost and complex execution, there is a search for standardized exercise tests that can predict this value in a single session. One of the methods described for this purpose is the lactate minimum test (LMT), which could be more accurate despite being adequate to predict MLSS. This study aimed to examine the impact of training on the speed corresponding to lactate minimum speed (LMS) and to apply new mathematical methods to evaluate the fitness ...
Schrurs C, Dubois G, Van Erck-Westergren E, Gardner DS.In-training racehorse physiological data can be leveraged to further explore race-day performance prediction. To date, no large retrospective, observational study has analysed whether in-training speed and heart rate recovery can predict racehorse success. Speed (categorised as 'slow' to 'fast' according to the time taken to cover the last 600 m from a virtual finish line) and heart rate recovery (from gallop to 1 min after exercise) of flat racehorses (n = 485) of varying age, sex and type according to distance (e.g., sprinter, miler and stayer) were obtained using a fitness tracker from a si...
Takahashi K, Mukai K, Ebisuda Y, Sugiyama F, Yoshida T, Hatta H, Kitaoka Y.Evidence suggests that positive pacing strategy improves exercise performance and fatigue tolerance in athletic events lasting 1-5 min. This study investigated muscle metabolic responses to positive and negative pacing strategies in Thoroughbred horses. Eight Thoroughbred horses performed 2 min treadmill running using positive (1 min at 110% maximal O uptake [V̇Omax], followed by 1 min at 90% V̇Omax) and negative (1 min at 90% V̇Omax, followed by 1 min at 110% V̇Omax) pacing strategies. The arterial-mixed venous O difference did not significantly differ between the two strategies. Pl...
Nankervis K, Tranquille C, Tacey J, Deckers I, MacKechnie-Guire R, Walker V, Hopkins E, Newton R, Murray R.Repeated exposure to water treadmill (WT) exercise could elicit kinematic responses reflecting adaptation to WT exercise. The study's aim was to compare the responses of a group of sport horses to a standardised WT exercise test (WTSET) carried out at three time points, week 0 (n = 48), week 20 (n = 38), and week 40 (n = 29), throughout a normal training programme incorporating WT exercise. Horses were recruited from the existing client populations of two commercial water treadmill venues for the purpose of this longitudinal, observational study. Limb, back, poll, wither, and pelvic kinematics...
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...
Riley JW, Chance LM, Barshick MR, Johnson SE.Hyaluronic acid (HA), a glycosaminoglycan found in joint synovial fluid, is administered to horses as an anti-inflammatory with lubrication properties. This experiment examined the effects of HA administered before and shortly after an exercise test on metacarpophalangeal (MCP; fetlock) and tibiotarsal (hock) joint range of motion (ROM). Horses were injected intravenously (IV) with placebo (4 mL, saline) or HA (4 mL, 40 mg) 24 h before performing a standardized exercise test (SET) on a high-speed treadmill and again at 6-h post-SET. Passive fetlock flexion was measured at 4 and 24 h post-...
Massie S, Léguillette R, Bayly W, Sides R, Zuluaga-Cabrera AM.Workload associated with the high frequency Colombian Paso Fino gait has not been evaluated. Objective: To determine the oxygen consumption (V̇O), heart rate (HR), stride frequency: breathing ratio, and hematology associated with the Paso Fino gait, including whether exercise-induced pulmonary hemorrhage (EIPH) occurs. Methods: Eleven Paso Fino horses. Methods: Prospective cohort study. Horses performed a standardized Paso Fino gait test across a wooden sounding board, simulating competition. V̇O and ventilatory parameters (tidal volume [V]; peak inspiratory and expiratory airflows [PkV̇, P...
Pineau V, Ter Woort F, Julien F, Vernant M, Lambey S, Hébert C, Hanne-Poujade S, Westergren V, van Erck-Westergren E.Gastric disease is highly prevalent in sport horses and may lead to poor performance, cause behavioral changes and impact welfare. Objective: Assess whether diet affects gastric disease and pain expression during riding, and whether it has an impact on physiological and locomotor variables during an exercise test, including jumps. Methods: Nine healthy show-jumping Warmbloods trained at the same stable. Methods: Prospective observational cohort study. The horses receiving a pelleted diet, high in sugar and starch (>30%), were examined at T0 and after 12 weeks (T12) of changing to a cooked, m...
Lendl L, Barton AK.This literature review focuses on diagnostics of equine asthma (EA), possible influencing factors on diagnostic techniques and latest developments in diagnosing horses during EA remission or with subclinical disease. Routine EA diagnostics include a clinical examination of the respiratory system with percussion and auscultation including a rebreathing examination, and clinical pathology including white blood cells and arterial blood gas analysis. Subsequent diagnostics include bronchoscopy to evaluate the amount and viscosity of respiratory secretion, bronchoalveolar lavage, and the cytology o...
Barshick MR, Ely KM, Mogge KC, Chance LM, Johnson SE.Methylsulfonylmethane (MSM) is a sulfur-containing molecule with reported anti-inflammatory and antioxidant activities. Exercise causes the formation of free radicals and stimulates inflammatory gene expression in leukocytes and skeletal muscle. The hypothesis that dietary supplementation with MSM alters the exercise-mediated inflammatory and oxidant response was assessed in unfit adult thoroughbred geldings. Ten geldings (6.7 ± 1.6 yr) were assigned to a diet supplemented without (CON, = 5) or with 21 g of MSM ( = 5) for 30 days. Following the supplementation period, horses performed a stan...
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...
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...
Wang T, Meng J, Wang J, Ren W, Yang X, Adina W, Bao Y, Zeng Y, Yao X.The purpose of this study was to explore the relationship between blood lipid levels and the differences in cardiac structure and function of trained and untrained Yili horses as related to exercise performance. We utilized quantitative lipidomics technology to elucidate how the differences in lipid compounds in the blood influenced performance outcomes. Sixteen 18-month-old Yili horses were selected, ten of which received a 15-week training regimen, and six were kept as untrained controls. Cardiac structure and function were assessed by echocardiography, while plasma lipid metabolites were de...
Coelho C, Vintem C, Silva AS, Santos C, Santos AM, Leite A, Souza V, Siqueira R, Filho HCM, Simões J.The present work aimed to evaluate the influence of a training programme on energy expenditure (EE), cost of transport (COT, cardiac beats to move the body mass during exercise) and metabolic power (Pmet) in young Purebred Lusitano horses used in dressage. With this purpose, nine male horses, ~4 years old, were evaluated before (M1) and after 6 weeks (M2) of a training programme that included 40-80 min of preparatory dressage exercises, 6×/week, individually adjusted. In M1 and M2, the animals were examined in a dressage field test (DFT), when heart rate (HR) and respiratory rate (RR), body...
Simões J, Santos AM, Santos C, Silva AS, Vintém C, Fonseca J, Coelho C.Show jumping is a popular and complex equestrian modality practiced by a athletes of different levels. However, most studies focus on elite athletes. Objective: The aim of this work was to assess the effect of a show jumping test (SJT), designed for novice athletes, on the physiological biomarkers and energy indexes of a group of horses, bred and trained in Portugal. Methods: In this prospective cross-sectional study, thirteen horses and their riders performed a SJT with obstacles set at 80 cm height using a heart rate monitor (M430 with H10 sensor). Physical examination and blood samples, for...
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...
Massie S, Vega LCC, Zuluaga-Cabrera AM, Bayly WM, Léguillette R.Colombian Criollo horses are bred for their smooth gaits that emphasize full collection and rapid footfall. The physiological demands of these gaits remain unknown. Our objective was to determine if oxygen consumption, ventilation, locomotor-respiratory coupling, and running economy differed between the trot or trocha and the gallop. Unassigned: 7 competition horses completed a controlled design standardized field test between January 10 and 20, 2025. Horses wore a cardiotachometer and ergospirometer to measure heart rate, oxygen consumption, and ventilation at the trot or trocha and the gallo...
