The 'rest' of the story

The competition season is over for most: Why, when and how to provide the off-season rest an equine athlete needs for optimum performance
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Feb 01, 2008


Paying attention to the 5 systems
For most of the country, the wind blows and the snow swirls. It is not quite foaling season, too early for breeding and, except for those clients chasing points and heading to warmer weather competitions, things are relatively quiet for most equine practitioners.

Now is the time to get a bit of well-deserved rest.

It's probably a good time, too, to take a look at the basic concept of "rest" in an equine training and conditioning program; very few horsemen and women give this topic the attention it deserves.

Most owners and trainers spend a significant amount of their time thinking about their horse's conditioning, charting workout times, recording speeds and distances and assessing fitness.

Owners will consult with their veterinarians as to nutrition for these performance horses. Decisions will be made on soundness issues and plans formulated to promote foot growth, muscle development and joint wellness. They may request any number of tests to look at various blood parameters and may even seek veterinary advice as to the overall fitness of their equine athlete and its readiness for competition.

Addressing the need for rest

But few owners or trainers ask about rest.

How much rest does the performance horse need in a conditioning/training program? When do you implement that rest period? What constitutes the best method of rest for exercising horses? How long does it take a horse to get back into condition after a period of rest?

It is beneficial for equine veterinarians to understand the research behind answers to these questions and to be able to advise their clients on this issue. Overtraining (the result of too little rest) is a very real concern in competition horses, often leading to serious problems requiring veterinary attention. Proper rest for performance horses ultimately may help eliminate some of these problems.

"Preparation of a horse for competition involves a combination of training (schooling) and conditioning," according to Dr. Hilary Clayton, a leading sports-medicine researcher and director of the Mary Anne McPhail Equine Performance Center at the College of Veterinary Medicine at Michigan State University.

"Training develops neuromuscular coordination and mental discipline," Clayton says, "while conditioning induces physiologic and structural adaptations that maximize performance and maintain soundness."

Conditioning affects 5 systems

There are five systems in the horse — cardiovascular, muscular, nervous, thermoregulatory and support structure — systems that must adapt during physical conditioning and each has a different time schedule for that physiologic change.

The cardiovascular system must improve its capacity to deliver oxygen to working muscles. Muscles must improve their capacity to use that oxygen, increase their efficiency to use fuel and improve the mechanisms for the removal/buffering of the metabolic by-products of exercise.

The maximal rate of oxygen consumption (VO2max) is a measure of the ability of cardiovascular, respiratory and muscular systems to work at full capacity.

The most substantial increases in VO2max occur during the first two to three weeks of training, with a 9 percent increase occurring in just 10 days, according to one study of Thorough-breds performing moderate-intensity exercise.

VO2max improvements tend to plateau within six to eight weeks of training. Increases in plasma volume occur quickly, while increases in red blood cells, hemoglobin and muscle mitochondria and capillaries take longer (two to six months).

The horse's temperature regulatory system is extremely important to its ability to perform maximally. The horse must increase blood flow to the skin, improve its ability to sweat effectively and adapt so that it has an earlier onset of sweating with exercise. These changes may require a minimum of two weeks to occur.