Page 92 - Speedhorse November 2019

WHEN HAS YOUR HORSE HAD ENOUGH?
Part of planning a preventive strategy for your horse’s training relies on knowing what situations and management decisions add stress and have potential to develop overreaching or overtraining.
Nancy S. Loving, DVM
by Nancy S. Loving, DVM
As your horse gets fitter, it is tempting to keep asking for more in his daily workouts. But, when is
it enough, or when have you passed a safe threshold? Perhaps everything seemed to be going just fine,
but suddenly your horse isn’t putting out as much as usual and he seems irritable and less cooperative when asked to perform his normal tasks under saddle. Not only is he not as interested in food, he also isn’t much stimulated by things happening around him. He just doesn’t seem himself.
These signs reflect that your horse is being
asked to do too much work relative to his ability to cope with the exercise stress. Terminology for this syndrome has specific meanings. Many might refer
to this as overtraining when, in fact, most horses engaged in performance and sport horse activities are more likely to experience a less severe syndrome called “overreaching.” Horses that train in high-intensity exercise like racing and high-speed sports are the ones that more commonly experience “overtraining.” This type of performance shutdown can happen to horses that aren’t yet adequately prepared and even to those that are well prepared for the exercise demands.
Let’s look at the differences in these two condi- tions and discuss ways to keep your horse mentally sharp and in peak fitness without overdoing the exercise demands.
OVERREACHING VERSUS OVERTRAINING
In any equine sport, accumulated stress of train- ing and competition can lead to fatigue if overdone; horses display standard responses to chronic fatigue. No matter if your horse is trained in racing, bar- rels, gymkhana, reining, roping, Eventing, dressage, competitive trail, endurance, polo, or other Western equestrian sports, the variety of signs of chronic fatigue will be similar.
The key difference between these two syndromes
is that a horse that is overreached recovers within days or at most a two-week period when given time to rest. In contrast, the chronically over-trained racehorse, for example, is one that may not recover for months or even years due to extreme stresses on his physiology; in some cases, the consequences could be career ending.
What possible signs might tip you off to a fatigue problem? You might notice:
• Decreased performance or lack of improvement in
performance despite on-going training.
• Decreased body weight by as much as 10%. Usu-
ally, weight loss is around 3% but this requires accurate scales to evaluate. Muscle glycogen (an energy source) normally adds to body weight by increasing water content in the muscles. Body weight reductions have more to do with dimin- ished muscle glycogen stores rather than result- ing from reduced feed consumption.
• Elevated heart rates during exercise. This is de- tected using a heart rate monitor.
• Delayed heart rate recovery, i.e. the time to return toward resting heart rate following exercise.
• Behavioral changes: head tossing, tail wringing, unwillingness to perform tasks, irritability, grumpy or nervous behavior – in humans, emotional changes are referred to as profiles of mood state (POMS) and are sensitive indicators of overtraining. Similar behaviors occur in horses if you just know to look.
• Less interest in interacting with other horses, including introduction of a new herd member.
Behavioral changes, such as head tossing, tail wringing, unwillingness to perform tasks, irritability, and grumpy or nervous behavior, are all possible signs of a fatigue problem.
90 SPEEDHORSE, November 2019
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