It’s no secret that eventing ranks among the most physically demanding disciplines for horses. Many horses are sidelined by injuries in training. Could monitoring fitness levels help identify horses most at risk for injuries?
To find out—and to see how common training injuries are— Dutch researchers followed the nine ponies and 20 horses who were selected to prepare for the European Eventing Championships in 2010 and 2011. For horses, the championship is a CCI***; the pony championship is a CCI**. The Dutch National Equestrian Federation selected the horses and ponies based on their performance during the preceding competition year. Carolien Munsters and fellow researchers from Utrecht University in the Netherlands used standardized exercise tests (SETs) to rate fitness. For horses, the SET consisted of four consecutive 1,000-meter gallops at speeds of 6.7, 8.3, 10.0 and 11.7 meters per second (or the horse’s individual maximum speed). Speed and heart rate were monitored, and blood samples were taken to measure plasma-lactate concentration (a measure of muscle fatigue) after each gallop and after a 10-minute cool-down walk.
The horses and ponies were tested at the beginning of the competition season in March and again after 11 weeks of training and competition. But just four horses and three ponies made it to the second test. The rest were all withdrawn from the selection group during the prep period.
The most common reason for withdrawal was “locomotor injury”— 10 tendon injuries, one fetlock-joint injury and two cases of unspecified lameness. The team veterinarian assessed the injuries. Six other animals were pulled because they failed to meet the criteria for the championship competition, and three horses were sold.
In all, injuries claimed 45 percent of this group. Other studies have shown injury rates ranging from 21 percent to 35 percent in CCI horses. “The higher percentage of injuries here might simply have been due to lower numbers and random variation but might also have been related to the fact that all animals competed at the top level,” Munsters writes. She adds Health Update that gathering similar information on event horses in other countries could help to determine if such high injury levels are universal and to understand the effects of training methods.
The study also showed a strong correlation between fitness level and injuries. Based on their first SET results, horses and ponies were sorted into good and average fitness groups. The average horses were far more likely to be injured while all the good performers stayed sound.
For 10 of the horses, heart rate and speed data were also recorded after all condition-training sessions at home. Horses who stayed sound had lower peak heart rates during condition training (about 186 beats per minute) than horses withdrawn later for injuries (about 200 beats per minute) even though speeds were comparable between the groups. In this study, at least, fitness level during training was a good predictor of which horses were most likely to stay sound.
This article originally appeared in the December 2013 issue of Practical Horseman.