By Nancy Jaffer
April 23, 2017
What type of footing should you put in your ring? The number of options is positively confusing—do you want an artificial surface? And if you choose that, will it include bits of rubber, fiber or wax? How about something more natural, such as sand? How should the surface be cared for and watered?
It’s an incredibly complex subject, but I thought the man with the definitive answers to those questions would be Dr. Jeffrey Thomason from the University of Guelph in Ontario. After all, he is an expert on equine hoof anatomy and mechanics, while the subject of footing (the effects of surfaces) also is a big part of his game.
So when he was one of the keynote speakers earlier this spring at the Rutgers Equine Science Center’s vastly informative two-day “Horses” symposium in Piscataway, I took the opportunity to get his thoughts on the subject. As his bio for the Rutgers program noted about his work, “the effects on limb loading of factors such as surface properties is key to improving equine performance, while reducing the high frequency of limb injuries.” And who doesn’t want to do that?
He was most generous with his time, but the bottom line is that I got no sure-fire footing recipe. Apparently, there isn’t one.
“It’s not a single-answer question,” he told me.
“The jury is still out, there’s no two ways about it,” the professor commented, pointing out, “It depends on the discipline.”
I did, however, receive a lot of information.
In his talk, he noted that risk factors related to the mechanics of motion involve not only the composition of the surface on which the horse is moving, but a number of other factors as well, including whether the activity is strenuous and/or repetitive, and shoeing status—is the horse barefoot or wearing shoes; if it’s the latter, do they have grips or caulks? There are discipline-specific injuries that include (to mention just a few) hock and suspensory problems in jumping and dressage, knee and pelvis problems in thoroughbred racing and navicular in jumping and general use.
Each stage of the hoof’s movement has different kinds of loading. The initial impact is shock. Then you’ve got the slip-and-slide, which is horizontal loading, and the weight of the force, which is vertical loading. Every type of load interacts with a different property of the surface. The first impact involves how much energy the hoof and leg have to absorb, depending on the hardness or softness of the surface. The amount of slide is controlled by the grip and we don’t yet know, he said, what an appropriate amount of slide involves.
In terms of what causes injury—do we want the foot to come to a halt? Definitely no, but then other than reining, we don’t want foot to slide out too much. Sponginess of the surface is important in the weight-bearing phase, because it will increase the amount of force on the leg.
The next step is linking the mechanics to the type of injury you might see, he said. Impact involves hock issues, slip and slide is probably deleterious to tendons; mid-stance, when the leg is vertical, puts 2 ½ times body weight on one leg, so “every tissue in the leg is wronged at that point.”
“Given you’ve got this partitioning out of different types of loading and interaction with different properties at different stages of the stance, every surface has a different combination. One that’s really good for cushioning the landing may actually increase the peak loading, and vice versa,” he pointed out.
Therefore, he added, we shouldn’t be looking at a single property of surfaces. Rather, we must look at them all in combination.
“That makes it complicated. That’s why we don’t have answers. It’s only 10 years into these kinds of studies.”
He also pointed out that among the risk factors for injury, “surface composition is nowhere near the top of the list.” More pertinent are the type and intensity of activity, how strenuous and repetitive it is and whether the animal is conditioned for the competition properly, which leads back to training methods.
Meanwhile, each type of artificial footing comes with its own set of problems. They’re all different, depending on how they’re constructed and who put them together.
Designers are experimenting with varying mixtures of the components, the percentage of rubber vs fiber, types of fiber, types of sand, he said. Clay with its little binding particles is another component. He said it’s a low percentage, 10 percent or less.
More questions: What kind of sand do you use, what’s the moisture content? How often do you water during an event? Water fed from underneath will superhydrate and then the water becomes part of the equation, not just the moisture in the surface, but the water itself has a hydraulic effect.
Water can give more of a cushion, he said, explaining, “Think of a waterbed, it has different properties than a regular mattress.” Systems that can do that are not inexpensive to put in and maintain, however.
He observed, “designers know what they’re doing and know the principles on which they design, but very few actually test forces” (to verify that their design does work).
Understandably, he won’t endorse any particular type of footing, or footing formula.
“We do not have enough information to state that definitively,” he said.
“A 100 percent perfect answer? The reality is not yet, (but) we should be able to get quite a bit closer than we are today. We’re answering basic questions but finding more questions every time we do. The rate of progress is increasing. What we’ll understand in 10 years is five times what we learned in the last 10 years.”
He mentioned it would be useful to check out the racing surfaces testing laboratory (www.racingsurfaces.org). It produces white papers on surfaces and how they’re tested. Although they are focused on racing, not showing, Thomason said, “The principles are the same; the outcomes are different, depending on the need.”
And certainly, you need a different surface for different disciplines. “One size doesn’t fit all,” said Thomason, who envisions the possibility of some kind of meter behind the harrow with a machine, that has a needle the driver can see, showing that the harrowing is appropriate for a certain discipline, as long as the needle is between the green lines. He said there’s no reason that couldn’t be done for all surface types, “so during the daily maintenance, you could recondition the surface to be appropriate for the use.”
So what should you do about your arena? He advises, “Find yourself somebody who’s reputable, because the good designers are good, they can get you the best product you can get for your needs.” Tell them about those, then get them to explain to you what they are doing.
“Interview a couple of them and see the different messages you get. Then make a decision on your best judgment.”
Added Thomason: “Realize that next time you want to put a surface in, your conversation will be very different, because there will be new information.” Rather than trial and error at work, “we should be progressing more toward knowing how the design will affect the horse. That has been the parameter that is missing.”
Remember, surface properties are just one of many risk factors. The intensity of the workload, speed, repetitions, that’s the biggest risk factor for injury, he said. That’s got the direct effect on the mechanics and loading of the leg.
“It’s loaded very differently in each of the different disciplines. Dressage is sufficiently different from show jumping that I think at some point they will have to be different surfaces.
“If you condition it for one discipline you’re going to injure horses in the other. If we know that is going to happen then it’s some kind of negligence. It becomes an ethical issue. We’re not there, but I predict we’ll get to that point where we have enough knowledge and say this surface isn’t good for this discipline.”
On the other hand, there definitely is some leeway. “If you condition a horse to work on different surfaces when they’re training then, they will be able to accept a variety of surfaces for competition too. (It’s like cross-training).
Riders of show jumpers who spend most of 12 weeks on a state-of-the-art artificial surface at the Winter Equestrian Festival in Wellington, Fla., often will try occasionally to take them to shows held on turf during that period, to give their horses a break. While there are many pluses to grass, it can’t take heavy use and weather can wreak havoc on it.
Thomason emphasized that research into surfaces needs more sponsorship. At least 10 different groups around the world are capable of handling it, Thomason said; they just need the funding..
“We’ve gone beyond experience and observation. We’ve got scientific measurement and it’s changing the name of the game.”
Want more details? The FEI has produced a white paper on the subject: http://inside.fei.org/system/files/Equine%20Surfaces%20White%20Paper.pdf