Effects of three warm-up regimens of equal distance on VO2 kinetics during supramaximal exercise in Thoroughbred horses

Health of Polo Horses

This literature review analyzes the historical development of polo, its organizational structure, the course of the game, as well as the breeding, rearing, and training practices of polo horses. Frequently occurring ailments, such as musculoskeletal injuries, respiratory diseases, and internal illnesses, are highlighted. Lameness is a major problem, with injuries to the superficial digital flexor tendon being the most common cause. Other notable diseases include exercise-induced pulmonary hemorrhage (EIPH), myositis, rhabdomyolysis, and equine infectious anemia (EIA). To ensure the welfare of polo horses, effective prevention and management strategies are crucial. These include proper training, the adaptation of the ground surface, appropriate shoeing, and compliance with animal welfare guidelines and association rules. Collaboration between associations, players, organizers, and veterinarians is crucial. Promoting responsible management practices and raising awareness among stakeholders can help ensure that polo continues to thrive while maintaining high animal welfare standards.

Influence of Stretching Exercises, Warm-Up, or Cool-Down on the Physical Performance of Mangalarga Marchador Horses

The Horse Agribusiness Complex is an important activity in the Brazilian agricultural sector. Mangalarga Marchador (MM) is the most numerous breed of horses in Brazil and its temperament and gait characteristics (4-beat stepping gait) allow for the constant growth of the breed and the performance of vs. equestrian activities. The training management currently adopted with MM horses is based on empiricism, and scientific support is necessary to improve the well-being of horses in competitions and maintain the physical integrity of these athletes. Therefore, this study aimed to verify the effects of stretching, warming up, and/or cooling down on their performance in marcha tests. 6 MM geldings (aged between 3 and 7 years and average weight of 400 kg) were used. The pre-experimental stage for the physical conditioning of the horses lasted 46 days. The experimental phase lasted 42 days and consisted of 6 marcha tests performed every 7 days. The experimental design was in a Latin square (6 × 6), in which each horse was submitted to the following exercise protocols: A) 50-min marcha test following the official regulations of the Brazilian Association of Horse Breeders Mangalarga Marchador (ABCCMM); B) 10 min of warm-up before marcha test; C) 10 min of cooling after marcha test; D) 10 min of warm-up before marcha and 10 min of cool-down after marcha test; E) 10 min of stretching before the marcha test; F) 10 min of stretching, 10 min of warm-up before and 10 min of cool-down after the test. Horses were evaluated before and after marcha tests for heart rate (HR), respiratory rate, rectal temperature, glucose, lactate, creatine kinase, aspartate aminotransferase and cortisol. Data were submitted to 2-way analysis of variance (exercise protocols and evaluation moments) and means were compared by Tukey's test (P≤0.05). The HR and blood lactate results indicated a beneficial effect of warm-up or stretching practices on the performance of Mangalarga Marchador horses submitted to simulated marcha tests in accordance with the official ABCCMM regulation and lasting 50 minutes.

What’s in a warm-up? A preliminary investigation of how European dressage riders and show jumpers warm-up their horses for training and at competition

Equestrian sports such as dressage and show jumping cause physical and physiological stress on the horses’ musculoskeletal structures, which can lead to decreased performance and injury. Warming-up prior to intense exercise can increase utilisation of the aerobic pathway, increase performance and decrease injury risk. Whilst duration of equestrian warm-up regimes has been reported, details of which gaits and skills related tasks, such as jumping and lateral movements, riders elect to use have not been evaluated to date. The purpose of this study was to understand dressage and show jumping riders’ decision-making when warming up at home and prior to a competition. Surveys (dressage: 39 questions; show jumping: 41 questions) were distributed online via social media. Mann Whitney U tests identified significant differences in warming up practice between dressage and show jumping riders. Most riders reported that a warm-up was beneficial for getting the horse ready for work, increasing responsiveness to aids, enhancing suppleness and relaxation, and decreasing injury risk. Both dressage and show jumping riders typically warm-up between 10-20 min. While dressage riders use the walk as their main warm-up gait, show jumpers preferred the trot. Both dressage riders and show jumpers incorporate technical skills in their warm-up such as lateral work, and quick transitions (when riders change gait for only few strides before changing again). Show jumpers include 4-10 jumping efforts, using different fence types. During a competition most dressage and show jumping riders agreed that factors such as perceived stress level of both the horse and rider, crowdedness of the arena, arena footing and size, as well as time allocated by the venue, were important factors that could impact the duration and content of their warm-up routines. Both groups of riders considered horses were sufficiently ‘warmed up’ when they were responsive to the aids and felt supple and relaxed.

An evaluation of factors affecting show jumping warm-up on subsequent show jumping performance in 1.30 m class

Show jumping causes physical and physiological stress on horses’ musculoskeletal structures, which can lead to decreased performance and injury. Appropriate warm-ups can enhance performance, decrease injury risk, as well as increase oxygen kinetics for better efficiency. Despite this, little is known for how warm-up routines affect show jumping performance. Forty-five warm-up routines of show jumpers preparing to enter the show ring were recorded and analysed. Kruskal Wallis analyses with post-hoc Mann Whitney U tests identified if the number of classes combinations completed, types of jumps attempted, warm-up duration, and time spent in each gait during the warm-up varied with rider and horse sex and age, and faults. Spearman correlations assessed if relationships occurred between warm-up duration and content, and the number of faults in the show ring, and horse age. Warm-up ranged from 3:51 to 62:46 min (median 15:09 min) and included at least two jumps (range 2-15). Walk was the most common gait, while upright fences were jumped the most. Knocking down or refusing a fence when warming up did not affect performance. Male riders jumped uprights twice as much as female riders (P<0.03) but this did not impact their performances. Jumping a class prior to the 1.30 affected warm-up, competitors spent longer on the flat before jumping in they had competed earlier in the day (P<0.05) and had fewer jump attempts if they had competed in the class just prior to the 1.30 m (P<0.007). Even though no significant differences were detected, combinations which accumulated >8 faults spent less time warming up. These results suggest warm-up tactics, riders and horses’ age and sex did not influence significantly fault accumulation in the show ring, however warm up routines were influenced by rider decision making and horse age.

Optimal speed in Thoroughbred horse racing

The objective of this work is to provide a mathematical analysis on how a Thoroughbred horse should regulate its speed over the course of a race to optimize performance. Because Thoroughbred horses are not capable of running the whole race at top speed, determining what pace to set and when to unleash the burst of speed is essential. Our model relies on mechanics, energetics (both aerobic and anaerobic) and motor control. It is a system of coupled ordinary differential equations on the velocity, the propulsive force and the anaerobic energy, that leads to an optimal control problem that we solve. In order to identify the parameters meaningful for Thoroughbred horses, we use velocity data on races in Chantilly (France) provided by France Galop, the French governing body of flat horse racing in France. Our numerical simulations of performance optimization then provide the optimal speed along the race, the oxygen uptake evolution in a race, as well as the energy or the propulsive force. It also predicts how the horse has to change its effort and velocity according to the topography (altitude and bending) of the track.

High-intensity training in normobaric hypoxia enhances exercise performance and aerobic capacity in Thoroughbred horses: A randomized crossover study

We examined the effects of high-intensity training in normobaric hypoxia on aerobic capacity and exercise performance in horses and the individual response to normoxic and hypoxic training. Eight untrained horses were studied in a randomized, crossover design after training in hypoxia (HYP; 15.0% inspired O2 ) or normoxia (NOR; 20.9% inspired O2 ) 3 days/week for 4 weeks separated by a 4-month washout period. Before and after each training period, incremental treadmill exercise tests were performed in normoxia. Each training session consisted of 1 min cantering at 7 m/s and 2 min galloping at the speed determined to elicit maximal oxygen consumption ( V ˙ O2 max) in normoxia. Hypoxia increased significantly more than NOR in run time to exhaustion (HYP, +28.4%; NOR, +10.4%, p = .001), V ˙ O2 max (HYP, +12.1%; NOR, +2.6%, p = .042), cardiac output ( Q ˙ ; HYP, +11.3%; NOR, -1.7%, p = .019), and stroke volume (SV) at exhaustion (HYP, +5.4%; NOR, -5.5%, p = .035) after training. No significant correlations were observed between NOR and HYP for individual changes after training in run time (p = .21), V ˙ O2 max (p = .99), Q ˙ (p = .19), and SV (p = .46) at exhaustion. Arterial O2 saturation during exercise in HYP was positively correlated with the changes in run time (r = .85, p = .0073), Q ˙ (r = .72, p = .043) and SV (r = .77, p = .026) of HYP after training, whereas there were no correlations between these parameters in NOR. These results suggest that high-intensity training in normobaric hypoxia improved exercise performance and aerobic capacity of horses to a greater extent than the same training protocol in normoxia, and the severity of hypoxemia during hypoxic exercise might be too stressful for poor responders to hypoxic training.

Risk factors for exertional heat illness in Thoroughbred racehorses in flat races in Japan (2005-2016)

BACKGROUND

Exertional heat illness (EHI) is recognised in horses, but few reports have investigated its risk factors.

OBJECTIVES

To identify risk factors for EHI in racehorses participating in flat races in Japan.

STUDY DESIGN

Descriptive epidemiology and retrospective unmatched case-control study.

METHODS

Between 2005 and 2016, veterinary records of horses diagnosed with EHI after flat races were reviewed retrospectively and data of the months from April to September were used for a case-control study. For each case, three control horses were randomly selected from starts between April and September. Race records of horses and estimated wet-bulb globe temperature (WBGT) indexes at the local meteorological observatory closest to the racecourse were investigated. To identify risk factors for EHI, univariable and multivariable logistic regression analysis was used.

RESULTS

Of 194 cases during the study period, 188 cases occurred between April and September. The highest incidence risk was in July (1.1 cases per 1000 starts, 95% confidence interval 0.84-1.45). In the final multivariable model, WBGT index, sex, race distance, age and bodyweight were associated with EHI. When WBGT index exceeded 28°C, the risk of EHI was considerably higher than <20°C (OR 28.5, 14.2-62.4, P<0.001). Compared with uncastrated males, geldings (OR 4.9, 1.8-13.3, p = 0.002) and females (OR 2.4, 1.5-3.7, P<0.001) were at high risk of EHI (P<0.01). Furthermore, races of >1600 m (OR 1.8, 1.2-2.8, P = 0.002), 4-year-old (OR 3.5, 1.6-7.9, P = 0.002) and ≥5-year-old (OR 3.9, 1.8-9.2, P = 0.001) horses and horses with low bodyweight (OR per 20 kg, 0.8, 0.7-1.0, P = 0.02) were associated with increased risk of EHI.

MAIN LIMITATIONS

The median straight-line distance between the racecourse and the local meteorological observatory was 14.2 km (range, 1.1-28.3 km). There was a lack of objective criteria of EHI due to the retrospective nature of the study.

CONCLUSIONS

We identified specific risk factors for EHI in racehorses. These results may be useful to the equine industry for reducing EHI occurrence in racehorses.

Development of a perceived exertion scale for dogs using selected physiologic parameters

OBJECTIVE

To develop a perceived exertion scale for dogs exercising on a treadmill and to assess intra- and inter-observer variability.

MATERIALS AND METHODS

Fifteen healthy client-owned dogs participated in paired exercise trials. Measurements of lactate, glucose, heart rate, temperature, respiratory rate and regional tissue oximetry were obtained before, during and after exercise. Perceived exertion scale scores were recorded during exercise and using video recordings to evaluate inter-observer variability. Correlations were evaluated using the Spearman's non-parametric method.

RESULTS

Thirteen dogs completed both trials. Dogs walked or trotted on the treadmill with an average perceived exertion score of 2 in both trials. Holter heart rate was positively correlated with perceived exertion scale scores from all observers for both trials. In trial 1, plasma glucose decreased in association with increase in perceived exertion and, in trial 2, cutaneous oximetry decreased, respiratory rate increased and temperature increased with increases on the perceived exertion scale. Inter-observer perceived exertion scale scores were positively correlated in both trials. There was no intra-observer variability between trials.

CLINICAL SIGNIFICANCE

The perceived exertion scale correlated with the measured physiologic parameters in dogs exercising at mild to moderate intensity. The perceived exertion scale was consistent and repeatable but larger study numbers and further validation are needed before it can be widely applied.

Studies on the exercise physiology of draft horses performed in Japan during the 1950s and 1960s

Although the total number of horses raised in Japan dramatically decreased after World War II, because draft horses were still used for farm work in paddy fields and on farms during the period of the 1950s and 1960s, a performance test for selecting better draft horses was needed. In order to determine the most suitable size of draft horses for Japanese farm conditions, the working power of horses weighing from 185 to 622 kg was evaluated by performing an endurance test, several kinds of working power tests, and maximum pulling power tests. Oxygen consumption during draft exercise was measured by the Douglas bag method in order to evaluate effects of draft workload under the conditions of different types of work (14- and 18-cm plow depths, cultivator, and tillage), traction methods (shoulder traction, shoulder-trunk traction, and chest-trunk traction), walking speeds (40, 60, 80, 100, and 120 m/min), and depths of water (0, 18, 36, and 54 cm) on energy expenditure. The relationship between energy consumption and pulse rate during exercise was also evaluated. A study of a performance test for draft horses was conducted to establish a new approach for evaluating draft horse performance using heart rate as an index. For this study, a beat meter for measuring heart rate was developed, and experimental protocols were used to evaluate the relationship between heart rate and workload. Although the research results obtained from these studies do not have particular relevance in the current day, these studies are valuable for understanding the history of equine exercise physiology in Japan.

Effect of a bandage or tendon boot on skin temperature of the metacarpus at rest and after exercise in horses

OBJECTIVE

To determine the skin temperature of the metacarpus in horses associated with the use of bandages and tendon boots, compared with the bare limb, at rest and after 20 minutes of lunging.

ANIMALS

10 adult horses.

PROCEDURES

Skin temperature on the bare metacarpus of both forelimbs was measured at rest and after lunging. Subsequently, a bandage was applied to the left metacarpus and a tendon boot to the right metacarpus and skin temperature was measured at rest and after lunging. Skin temperature was measured with fixed sensors and thermographically.

RESULTS

Mean ± SD skin temperatures of the bare metacarpi were 14.1 ± 2.4°C (left) and 14.1 ± 3.4°C (right) at rest, and 14.4 ± 1.8°C (left) and 13.6 ± 2.6°C (right) after exercise. Skin temperatures under the bandage were 15.3 ± 1.6°C at rest and 24.8 ± 3.6°C after exercise. Skin temperatures under the tendon boot were 15.3 ± 2.6°C at rest and 20.6 ± 2.9°C after exercise. Skin temperatures under the bandage and tendon boot were significantly higher after exercise than at rest. Skin temperatures at rest were not significantly different with a bare limb, bandage, or tendon boot.

CONCLUSIONS AND CLINICAL RELEVANCE

Skin temperature of the metacarpus in horses increased significantly during exercise but not at rest when a bandage or tendon boot was used. The authors speculate that both a bandage and a tendon boot accelerate the warm up phase of exercise. Further research should focus on the effects of warm up and maximum exercise on the temperature of other anatomic structures such as tendons.