The effort produced by the rider

Any physical activity subjects the organism to significant physiological modifications. These are variable and depend on several parameters such as :
    • Level the activity is practiced at
    • The intensity
    • Individual parameters such as age, weight, aptitude, medical history…

Effort tests enable a precise assessment of the physiological modifications the body is subjected to during effort, and  therefore also assess the athlete’s fitness level for field tests, or to prevent cardiovascular risk factors during laboratory tests.

Laboratory tests

Laboratory tests are conducted on an indoor bike, rowing machine, or treadmill (figure 2). These tests assess heart, breathing and metabolic response, under medical supervision. The aim being to detect any abnormalities and estimate physical potential.

Similar tests are carried out on the horse athlete, on a treadmill in progressive stages, under veterinary supervision. These tests measure more parameters than field tests, but more importantly enable detection of pathologies and more specifically of breathing pathologies which may only become apparent with effort.

Tests in the field (Luc Léger, Léger-Boucher, Vameval, Cooper…)

The field tests aim to establish a training programme from evaluting MAS (Maximum Aerobic Speed, or speed at which the runner’s maximum oxygen uptake occurs, VO2max). The protocol is different acording to the test conducted.

Cooper test

The Cooper test calculates VO2Max after running for 12 minutes non-stop, at a constant speed and as fast as possible. The distance covered in 12 minutes gives an approximation of VO2Max = 22,351 x D – 11,288.

Luc Léger ou Vameval test

(Figure 3), this test consists in increasing one’s speed by 0,5km/h between two points situated every 20m. The runner should reach the following stage at the blow of a whistle. The test ends when the runner does not reach the cone at the required speed. The MAS is then estimated with a conversion chart.

These tests are easy to implement, but to assess the athlete’s stamina potential, they require of the athlete a good mastery of running techniques. VO2Max is an easy parameter to assess, useful at the start of the season, after a break due to injury or to a training problem, but while keeping in mind that this parameter is not the only one to influence performance.

Parameters

To assess the horse’s aerobic capacity the reference parameters calculated from track tests are S200 (Speed at which the heart rate reaches 200 beats/minute) and S4 (Speed at which lactate concentration reaches 4mmol/l).
These parameters are calculated from the following :

• Continuous measurement of heart rate (figures 4 and 6), which reflects effort. For both man and horse, a cardio frequency meter is composed of a belt around the thorax, which detects heartbeat and sends the information to a watch. The data can then either be read directly, or transferred to a computer so as to follow and optimise training programmes. The latest versions are equipped with a GPS. Speed and topography are integrated to analyse intensity of the effort. One of the benefits of using a cardio frequency meter is to analyse the athlete’s progress in terms of heart rate.
• Lactate concentration (figure 5), shows up muscle condition at the end of each stage.  This is most used for the horse. The quantity of lactates present is propotional to the intensity, length , and type of exercise. It is one of the refernce points used to plan a training programme. (For more information : Couroucé  A., 1995).

Figure 6 : On the left an example of the recording of the heart rate (in red) and the speed (in blue) during a training period for an eventing horse. On the right, an example of the heart rate recording of a 21 year old riding school rider during a flat work session (Galop 7 (equivalent to BHS stage 4) infrequent rider).

Studies are few and far between, with results thet differ significantly depending on the population studied, the level and the discipline.

« I feel exhausted after cross country….. »

Lactate concentration

Lactate concentration and heart rates have been measured for event riders.  Of course, lactate concentration varies, and depends on several parameters, particularly on the horse being ridden. Nevertheless the values were high, above the aerobic threshold, which indicates latic anaerobic activity. When lactate concentration is high at the end of a cross country course, it can be difficult  to be at one’s best to complete a second round on another horse for example. The rider’s fatigue is great enough to disturb some motor reactions (Auvinet, Galloux, 1993).

O₂

Measuring an event rider’s oxygen uptake showed a significant effort (80 % of Maximum heart rate reached  on average over the course, and  V02max reached for 20 % of the time)  over a cross country training course, with no specific difficulties (Berlanger 2008, figures 7 and 8).  A competition environment, with higher stress levels than during training most probably leads to almost reaching V02max.

« It depends on the horse I’m riding… »

Variability of the energy expenditure according to the horse being ridden has been demonstrated for flat work and show-jumping (Devienne 1999) with V02max increasing significantly when riding an « unknown » horse. Amateur riders on a novice show-jumping track reach 75 % of their V02max during training.

Figure 7 : equipment for measuring gas exchanges to determine VO2max : Maximum oxygen uptake, a parameter used to determine aptitude for intense prolonged effort. Expressed in ml/kg/min, for the human it can reach 70 to 90 ml/kg/min and between 130 and 165 for the horse. The difference stems from the fact that the heart rate of a horse in exercise is considerably higher, and the horse can increase its resting heart rate significantly. Horses are unique in their capacity for oxygen uptake.

All these measurements show that the rider’s metabolism is  considerably solicited when riding, and that good aerobic capacities are a factor in determining rider performance. They also show that an increase of this aerobic capacity can be achieved with several hours a day of intense practice, which is not the case of many competition riders.  General and specific physical preparation therefore appears essential..