Riding on the Right Surface: Footing Considerations with Your Horse’s Health in Mind
In this excerpt, adapted from Your Complete Guide to Equine Arenas, equestrian journalist and horsewoman Abigail Boatwright explains some of the key factors in ensuring our horses’ health, from the ground up.
Grass surfaces have historically been used for horse training and competition arenas. However, with climate issues, year-round use, required maintenance, demanding performance maneuvers, and heightened injury risks, there’s been an increase in the use and availability of synthetic surfaces. Grass is now less common for performance and professional arenas.
In absence of grass, most arenas are now comprised of mixtures of sand, silt, clay, and additives, such as woodchips, rubber, or fibers. Even though we’re working with just a few ingredients, many factors can change how a footing material feels and behaves.
Consistency is crucial to a good arena surface. While a horse can adapt to a range of surfaces, training on dramatically different surfaces may negatively impact performance and can be associated with injury.
There’s a conundrum, though. Unlike surfaces designed for human athletics, an arena footing ideal for equine performance is not always ideal for long-term soundness, according to studies cited in “Equine Surfaces White Paper” (published by the FEI). Footing for any equine sport should minimize concussion—of the hoof—through energy absorption, but still rebound power to aid performance. Here are a few terms used in the “Equine Surfaces White Paper” and throughout the horse world that need to be understood in order to choose and maintain arena footing with your horse’s health in mind:
Shock Absorption—This is either frictional and comes from particles being displaced, or structural, where shock absorption is achieved by compacting particles that will regain their shape. A surface’s firmness against impact, and the amount of cushioning it has, determines how much a surface can absorb shock.
Shear Strength—When a hoof lands on a surface, the shear strength is the amount of resistance the footing can offer to keep the hoof from moving horizontally. This needs to be optimized for specific events—for example, barrel racing requires higher shear strength to avoid potential slipping. Shear strength depends on moisture content, temperature, and the composition of the arena material.
Hardness—This is how much resistance a material has against penetration with a defined object and a defined amount of pressure. It’s difficult to measure hardness accurately on arena surfaces. It is related to stiffness—the ratio of applied force to deflection.
Response Time—The time between deformation of the surface when weight is added—a hoof landing—and the subsequent elastic recovery—a hoof leaving. If the elastic recovery occurs too quickly, increased force will be taken on by the horse’s limbs.
Loss of Energy—When a hoof impacts a surface, some of the energy from the collision is lost. The amount depends on the elasticity of the surface’s top layer.
Consistency—The Oxford English Dictionary defines consistency as “conforming to an unchanging pattern.” When referring to arenas, we are talking about the consistency of the material around all areas of the arena, and from one point in time to another. Moisture content is the largest variable in footing’s consistency. But inconsistent depth contributes the most to the risk of lameness, according to a study on dressage horses.
Impact Firmness—This is the shock experienced by the horse and rider when the hoof contacts the surface. This relates to the hardness of the very top surfaces and its initial stiffness when your horse’s hoof lands on it. Concrete has a very high impact firmness. When you put a thin layer of sand on top of concrete, you have far less impact firmness, while still having good support. When you place wood over wet clay, you have good impact firmness, while still having some cushion as the horse steps.
Cushioning—The supportiveness of a surface to the horse compared to how much “give” it has. You can also think of this as force reduction—how the layers of the footing absorb impact—when a hoof lands. A surface lacking good cushioning is stiff, or hard. One example of footing with good cushioning, but little elasticity, is a sandy beach with dry, deep sand.
Photo by Abigail Boatwright
Responsiveness—This is how “springy” the surface feels to the rider and the horse. Think of a trampoline. When you push downward because of your weight, it springs back and even bounces you upward. If the timing of the rebound matches the horse’s movement, it will feel springy. If not, it will feel “dead” with no springiness to it. For example, a surface that is heavily compacted could rebound too quickly, which makes it feel stiff or “dead.”
Grip—The amount of sliding—horizontal movement—the horse’s hoof does during landing, turning and pushing off. This comes from the interaction between the horse’s hoof and the materials that interlock and hold the surface together. Friction on the top layer affects how your horse’s hoof lands. You want a little bit of slide to help absorb the impact, but not so much that the surface is “slippery.” Your horse needs to be able to push off the layer just below the surface. A high grip surface will stop your horse too quickly, while too little grip will allow him to slide too much.
Uniformity—How consistent the surface feels as the horse moves across it. An arena can look level, but the impact firmness, cushioning, responsiveness, and grip can still vary. Your horse can handle gradual changes across an arena, especially if they’re visible. But sudden or wildly variant changes can cause your horse to trip or become injured.
Consistency Over Time—This refers to how much the surface changes with time and use. Sand can break down into smaller and smaller pieces, which turn into silt. Moisture changes can affect the grip, cushioning, and other factors as the arena dries out during a day. Horses working on the footing can alter consistency along the track and in other high traffic areas.
Surface Composition—Composition varies by region and discipline. For example, riders in the United Kingdom often use surfaces that are comprised of sand and rubber, sand and woodchip, and sand and polyvinylchloride (PVC). Common additives for dressage or jumping arenas include synthetic or natural fibers, rubber, and cloth or felt strips. A polymer or wax coating can also be applied to sand. This binds the footing material together and creates a hydrophobic—water-repellant—coating.
Footing Takeaway: To create the best footing, you not only need the right materials in the correct combination, but the moisture level must be adjusted continually and the arena surface needs proper dragging to promote a consistent loose depth on top of your arena base. You cannot have good footing, with even the best materials, without care and water.
This excerpt is adapted from Your Complete Guide to Equine Arenas by Abigail Boatwright is reprinted with permission from Trafalgar Square Books. You can purchase a copy of the book here.
