Get A Handle on Your Footing
- Jan 1, 2002
Good footing is important for optimizing performance and reducing the risk of lameness. The main reason why sport horses retire early is due to osteoarthritis from constant wear and tear of the joints, sometimes from long-term schooling on bad footing.
The main symptom of bad footing is decreased performance. A horse might not feel secure enough in his footing to move as well as you know he can, or be as willing to jump or slide if it hurts him. In addition to training difficulties, you also might encounter soft tissue injuries of muscles, ligaments, and tendons.
Horse Movement and Footing
When your horse's foot hits the ground, it pushes forward and downward on the footing. The foot is still moving when it lands, so the hoof has to be decelerated and brought to a stop before the horse can push off to take another stride or launch himself forward to jump. Good footing allows the hoof to decelerate gradually. With poor footing, the hoof will either keep sliding and strain soft tissue, or stop too quickly and cause joint injury.
For example, if a horse lands on cement, the downward motion of the foot stops very quickly because there is no give in the surface. "That is very bad footing in terms of injury," says Hilary Clayton, BVMS, PhD, the Mary Anne McPhail Dressage Chair in Equine Sports Medicine at Michigan State University. She has conducted research on surfaces and how they relate to equine performance and health.
"What happens is a deceleration wave shoots up the horse's leg. And that deceleration is damaging to the bones and joints. But if you have a surface such as sand that moves a little bit with the horse's foot, then the deceleration is more gradual. If in the sand you've got some wood product or rubber that's a little bit cushy, then some of that energy of deceleration goes into deforming the rubber or the wood and saves the horse's leg.
"Good footing allows the horse's foot to move a little bit upon landing," she emphasizes. "But when the horse goes to push off, you don't want footing that gives too much. Everything in footing is a balance: You need some give, but you don't need too much."
Ideally, Clayton says, a horse's hoof should be able to push into the footing and slide forward a little when it lands. The footing should allow the toe to cut in slightly, but the footing should also help the horse's foot remain stable as it pushes off.
Wayne Gregory, general manager of Footings Unlimited, says that there are four main problems with footing that can cause injury: base failure (or a base that has not been created properly), too much surface material, too hard of a surface (usually due to compaction), and too much additive.
Footing and Performance
When you're working on a surface that's comfortable for the horse, he'll move better. Patchy or uneven footing will cause him to lose confidence and shorten his stride. Footing that's slippery is an immediate danger to horse and rider due to the risk of falling.
Footing that is too hard, or frozen, will cause a horse to creep along with not much elevation to his stride. If the ground is just frozen and crusty on the top, harrowing should improve footing conditions.
Horses also have trouble getting out of deep footing, and they can get tired more quickly due to the extra muscle effort. There are no studies to associate certain injuries with footing that is too hard or too deep, but the same type of injuries are associated with both, but they happen for a different reason.
Jumpers have a greater need for secure footing on take-off, and a forgiving surface because of the higher impact on landing (especially over bigger obstacles).
"The smaller fences don't require a horse to project his body mass significantly higher into the air. Fences that are one meter are similar to the canter stride," says Clayton. "When they start jumping bigger fences, they have to raise their centers of gravity higher and there are bigger increases in the forces. They then require footing that offers more cushion."
It is important to school consistently in good footing. Hacking, showing, or riding in poor footing every once in awhile will probably not hurt your horse. It's the surface you are working on for weeks, months, or years that is going to cause problems. Clayton says to use good judgment.
"If it's very bad or slippery, you're risking an acute injury that can put your horse out of action for a long time. If the footing is hard but consistent, there is less risk of acute injuries in most sports, except those performed at high speed, but you should ride more conservatively than on a good surface."
Types of Footing
There are four types of footing products--sand, wood products, commercial rubber products, and polymer-coated sands. Most manufacturers recommend mixing wood and rubber products with sand. Sand gives your footing the most grip, while the wood and rubber products provide spring or cushion.
Sand comes in round and angulated forms. Round sand is not a good choice for footing as its shape makes it unstable. In fact, it is much like dry beach sand that pushes and rolls under your feet as you walk. Angulated sand is a better choice because its shape allows the grains to fit together more tightly, providing more stability.
Wood products include wood chips, sawdust, and shavings. Slipperiness is a problem with arena surfaces made totally from shavings because there is low friction between them, so they just slide over each other if the shavings are fairly deep (this is known as shear). Shavings also break down and turn into dust. How quickly they break down depends on how often the arena is used.
The benefits of wood products include adding "spring" to a sand mix and absorbing water. Also, wood products usually are inexpensive and are almost always readily available.
Commercial rubber products come from two main sources--recycled tires and virgin rubber. The benefit of rubber products is the tremendous spring they give when mixed with sand or coated sand footing. However, Gregory says the benefits come not from the source, but from the different shapes and types of rubber. The type of rubber used depends on the problems of the arena or the discipline using the arena. For instance, granular rubber prevents compaction while providing cushion, while flat rubber does a better job of providing stability. The second factor when choosing a rubber product is particle size. The larger the particle, the less likely it is to stay uniformly mixed in, thus creating inconsistent footing, says Gregory.
"Ideally, you want it to be the size of your pinky fingernail or smaller," he says. "However, this is something people have to be careful of since it is cheaper to just grind rubber into larger pieces. In essence these become like small stones."
One word of caution: All-rubber arenas are not recommended as they get slippery and the footing floats when it's wet.
Clayton is beginning research on rubber footing and how much rubber is beneficial in a mixed surface arena. By measuring the impact shock with an accelerometer on the horse's hoof, Clayton will be able to see how quickly the horse's hoof is decelerated based on the amount of rubber in the sand.
Polymer-coated sands are angulated sands that are coated in high-tech polymers. These are the only footings that come with a written guarantee to not produce dust or mud. However, this type of footing is very expensive.
What About Turf?
Turf is a wonderful surface to work on, provided it's kept at the perfect moisture level. Turf allows gradual deceleration as the hoof hits the ground, and it allows the toe to dig in when pushing off for the next stride. The roots help stabilize the soil, allowing the hoof to dig into the ground and push off for the next stride. However, as the horse runs the impact of the hoof compresses the ground, which eventually rips the roots apart, Gregory says.
The properties of turf vary with the moisture content of the soil. If the soil dries out it can get very hard, has higher impact shock, and the toe cannot dig into it. If it rains too much, turf can get slippery or deep and muddy. Turf is very difficult to maintain in a perfect state. You can't control the amount of rain, and it wears out if you get a lot of horses working on it.
Step One: All arenas must start with a very solid and level base. It must be impenetrable to hooves and water. If your horse's hooves can bite into the base, or water is able to seep in, very soon you'll have ruts that will make the footing uneven and unstable. The base should be as hard as asphalt, and it normally will be made of crushed stone, blue stone, decomposed granite, road pack, or crusher run, depending on the materials available in your area. Some people use clay, which is cheaper if it is available.
The depth of the base depends on the quality of the material. "As a general rule, use no less than four inches after compaction and no more than 10 inches," Gregory recommends. "The single most important part of the arena is the base. Do not skimp on the base. Ninety-nine percent of arena failures are base-related."
Your goal is to have a well-draining surface with two to three inches of surface material. A hard, non-permeable base should be graded so that water will run off, while a base that allows water to drain through it should use a drain tile. You should only grade at 1-2%, otherwise horses will be going up and down a hill or across a slope all the time. It is also recommended to place an arena on high ground so that water will not drain into it.
Gregory suggests working with a local contractor or footing company since many will provide advice.
Step Two: For the cushion, add sand and the additive you've chosen--rubber or wood. If you are putting in a new arena, keep in mind that it's easier to add footing than to take it out. English disciplines use 1 1/2 to three inches while western disciplines will use three to six inches. It is essential to keep footing level and consistent--many times the rail might have one inch of footing while the middle is five inches deep. This can really throw a horse off, and that's when injuries occur, Gregory says. He recommends regularly measuring footing.
Gregory says that the rule of thumb for additives is that less is better. "When adding these to your arena, never apply more than two pounds per square foot." However, he says this recommendation can vary based on the company providing the footing.
He cautioned that if a horse trains on a surface that is too cushiony, it will decondition the horse. When the horse changes locations, such as for a show, the horse might not be conditioned for that type of footing, and he will perceive that footing differently. An additive should not provide too much bounce.
Step Three (optional): In certain situations--such as dusty arenas or when the sand is unstable--you might need to add dust control or bonding agents. These agents can hold footing together, keep the sand from rolling, stop footing from getting too deep, and keep loose footing from blowing away.
Some agents can add more shock absorption to your surface material and help control the amount of moisture. Some, such as calcium chloride, prevent footing from freezing. For more on dust control and bonding agents, see "Dust Control and Bonding Agents" at left.
The best way to prevent arena problems from occurring is to pay close attention to footing maintenance. Some arena problems can be solved with frequent dragging and watering. Without dragging, ruts can develop along the arena wall and the corners can become compacted. The amount of dragging will vary with the surface materials and with how much the arena is used. If a lot of horses are using an arena on a daily basis, dragging every day might be needed. If the arena gets used infrequently, dragging once a week might be all that is needed. The more you allow your footing to be inconsistent, the more likely it is to affect your base. Footing loses its spring and bounce without water and maintenance.
In addition to dragging and water, adding footing when the surface thins out can improve conditions. Adding rubber and coarse sand can help. Wood products help in the short term. Also, one should keep a vigilant eye out for foreign objects such as thrown shoes or nails.
Your investment in your footing (both labor and money) can help protect your number one and most important investment--your horse.
Top Five Footing Problems
1. Problem: Inconsistent footing. Uneven or patchy footing hurts your horse's performance confidence.
Cure: Usually the culprit is the base. Consider taking off the surface material and re-rolling the base to pack it, then re-applying the surface material. If you longe horses in your arena, try to longe in different areas to avoid making a circular rut.
2. Problem: Stones and foreign matter can cause bruised hooves.
Cure: Organize a stone-picking party.
3. Problem: Surface is too deep for the discipline. This type of footing trouble can cause soft tissue injuries.
Cure: Water acts as a bonding agent, so water your arena so that it gets wet all the way through. This is the most common type of footing mistake. It increases the surface tension and that tends to hold the footing together. Deep footing fatigues muscles quickly and puts a strain on tendons and ligaments.
4. Problem: Surface is too hard. This jarring type of footing can cause osteoarthritis.
Cure: Sometimes hard footing is a sign of insufficient cushion. To fix it either add sand, wood, or a rubber product, or water your arena. (In this case, the water softens the footing.) If footing is hard due to compacting, drag or harrow your arena.
5. Problem: Use of manure and used shavings as surface footing.
Cure: This kind of footing is only good for extremely dry and hot climates such as in desert regions. Manure footing can get very deep and boggy. It's also an unappealing footing--it smells and draws flies. Take off the surface and replace with a clean mixture.
About the Author
Sharon Biggs Waller is a freelance writer for equine science and human interest publications. Her work has appeared in several publications and on several websites, and she is a classical dressage instructor.
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