The power of cold therapy

Whether treating new trauma, managing healing injuries or simply helping keep hardworking horses sound, cold therapy is a powerful tool.

It sounds almost too good to be true, like the subject of a pitch from an old-timey snake-oil salesman: an easy-to-use, one-step, drug-free therapy that can minimize the effects of a recent musculoskeletal trauma and accelerate recovery from old injuries. And you’d be right to raise an eyebrow, thinking, “That cannot possibly exist.” But it does, and it really is that good.

Cryotherapy---or, more simply, cold therapy---is one of the most effective methods for alleviating soft tissue-related aches and pains of hardworking horses. Whether it takes the form of ice, frigid water or one of a growing number of commercial “chill-down” products, cold therapy can aid the healing of musculoskeletal injuries both new and old, as well as help prevent them.

Yet this powerful technique is, generally speaking, underutilized by horsemen. “Cold therapy isn’t applied as often as it could be but is very useful,” says Bruce Connally, DVM, a veterinarian in Berthoud, Colorado. “It’s been proven in both horses and in humans to work very well.”

If you’d like to try using cold therapy on your horse, you can start today. Right now, even. Simplicity is a big part of its appeal: Turn on the hose, empty an ice tray and you’re ready to go. But this form of therapy will be more effective if you understand something about the physiological changes set in motion when cold meets limb. Here’s what you need to know.

Cold as a first aid

The benefits of cold therapy in treating acute injuries will be familiar to anyone who has plopped an ice pack on a newly twisted ankle. Something similar happens when you use ice to ease the trauma of a horse who knocks his fetlock on a log or gets nailed on the hindquarters by a kicking pasturemate.

For starters, cold has an analgesic effect, which means it more or less numbs tissues that it touches. This makes the horse feel better almost immediately.

Meanwhile, another important physiological process is triggered by the cold. When a horse knocks a knee, pulls a tendon or otherwise injures himself, damaged blood vessels in the affected area begin to leak fluid into the surrounding tissues. This sets off an inflammatory cascade that we see as swelling and the horse feels as pain. Left alone, this leaking will stop naturally in about 12 to 36 hours, and the body’s natural “cleanup” effort will begin as part of the healing process. Dramatically cooling tissues at a new injury site, however, causes the blood vessels to constrict, limiting the leakage that leads to inflammation. This means there is less for the body to clean up later, shortening total healing time.

“The benefits of cold in the acute stage [first two to three days after the injury] are great,” says Kent Allen, DVM, a sport horse veterinarian in Middleburg, Virginia. “In those first days the cold therapy will slow blood flow, reduce pain perception and limit the amount of inflammatory mediators being released into the area. Thus it lowers cell metabolism, muscle contractility, nerve conduction, and significantly reduces the inflammatory response.”

Application tip: In the case of acute injuries, time is of the essence. The moment you notice a lump or a limp, apply cold to the area, but keep an eye on your watch. “You only need to do it for about 20 or 30 minutes at a time,” says Connally. “You don’t have to do it continually.” In fact, continual cold can damage tissues, and you’ll want to allow for at least 30 minutes between treatments. For maximum effect, follow a 20-minutes-on, 30-minutes-off schedule as closely as you can for the first 36 hours after an injury.

Cold for older injuries

Even after the acute phase of an injury has passed, cold therapy can still aid in recovery. “Another use of cold therapy, which many people tend to forget, is during rehabilitation,” says Katie Seabaugh, DVM, of the University of Georgia and diplomate of the American College of Veterinary Sports Medicine and Rehabilitation. “After the injury is healing, it is helpful to incorporate cold therapy into a recovery plan.”

Just as in application to an acute injury, the benefits of cold therapy in rehabilitation hinge on its vasoconstrictive effects. But when it’s applied to older injuries there’s a twist.

In treating acute injuries, the constriction of blood vessels by cold limits leakage and damage in tissues. In a rehabilitating horse, however, the leakage has stopped and it’s the return of blood to the area after the cold is removed that is most helpful. The renewed circulation brings a “cleanup crew” of white blood cells and natural chemicals that destroy dead cells and clean up physiological debris. This cooling/warming cycle created by intervals of icing also generates a “pumping” action in the tissues that can encourage and speed healing.

Even after healing is well underway and swelling has dissipated, it’s often wise to continue cold therapy even as the horse resumes his normal regimen.“If the horse has been off work for a long time during recovery, perhaps from a tendon injury, and is just starting exercise again, it is beneficial to apply cold therapy when that injured area is put back into work,” says Seabaugh. “This can help minimize possible stress and inflammation as you get the newly healed tissues working again.”

Application tip: During the rehabilitation phase of an injury, cold therapy doesn’t need to be applied as frequently as in the acute phase. One 20-minute session of icing after exercise will usually be adequate.

Cold for faster athletic recovery

Cold therapy can also become part of a horse’s wellness regimen after strenuous athletic effort. When a horse is working hard, capillaries that serve his muscles, tendons and ligaments expand to bring in needed blood. When work stops, however, that excess flow can persist and the now-unneeded fluid can bring with it enzymes associated with inflammation. As these fluids pool in the area, they make the horse sore and stretch tissues, which can lead to stocking up both in the short and long term. You can prevent most of this with cold therapy, which will help close up those vessels, restoring post-workout circulatory conditions quickly.

The effectiveness of post-workout cold therapy to hasten recovery is well documented in human athletes. “One article, for instance, showed the effectiveness of cold water immersion on post-match recovery in elite football players,” says Seabaugh. “The players participated in a game and then completed performance tests 24 to 48 hours after the game, after being randomly assigned to different groups. One group utilized passive recovery, another utilized cold therapy recovery and another used contrast water therapy [hot and cold]. The only group that showed a significant beneficial effect was
the group that utilized cold-water immersion. Those athletes came back to peak performance faster and had less pain and fatigue after the match. Cold water immersion helped them get back to desired performance levels quicker.”

After-activity icing has also been shown to help with the soreness that can accompany athletic efforts. “Another study looked at delayed-onset muscle soreness in humans, which is the stiffness/soreness you tend to get two days after the event,” says Seabaugh. “The cold water immersion reduced this delayed-onset muscle soreness after exercise.”

It’s no surprise that many post-game television interviews are conducted with athletes immersed in tubs of ice, but it’s still not a particularly common practice for horses outside of the racing world (see “A Time-Tested Technique,” opposite).

“Human athletes often use ice packs taped to their shoulders or use an ice bath after a performance,” says Seabaugh. “In racing, however, and in some performance disciplines, we see horses after a race or a strenuous workout standing in buckets of ice water or ice boots up to their elbows or past the hocks. These methods are being utilized by some parts of the horse industry, but there is not a lot of research on this. As we start to pay more attention to our equine athletes, however, beyond just racehorses, we will find there are benefits.”

Application tip: Keep it simple when incorporating cold therapy into your post-workout care routine. After the horse has been walked until his respiration rate has returned to normal, apply whichever cooling method you choose to his limbs for about 20 to 30 minutes. There’s no need to repeat the process if you’re simply helping him recover as opposed to treating an identified injury.

“You don’t get any additional benefit if you use cold therapy longer than about 30 or 40 minutes because after that you start getting the vasodilation effect,” says Allen. “Standing a horse in a bucket of ice all day doesn’t provide any more benefit. Using the cold too long is actually counterproductive.”

Cold therapy methods

Regardless of why you are using cold therapy, your options for applying it are the same. From the simple to the high tech, all techniques have the same ultimate goal: to lower the temperature of targeted tissues. “Our target temperature within the tissues should be somewhere between 10 and 15 degrees Celsius, which is about 50 to 59 degrees Fahrenheit,” says Seabaugh.

The simplest and most common form of cold therapy is hosing---running a stream of cold water directly over the area. This, however, isn’t likely to lower tissue temperatures to the desired range. “[Hosing] is the most popular method, and your veterinarian may tell you to cold hose an injury or a limb for 15 to 30 minutes,” says Seabaugh. “This is better than nothing, but it typically does not achieve cool enough temperatures needed for maximum benefit.”

A bucket of water supplemented with ice will be cold enough for effective therapy, if you can convince the horse to stand in it. (You may hear advice to add rock salt to the mix to further lower the temperature of the ice bath, but that can make the mixture too cold, damaging tissues. Stick to straight ice and refresh it as necessary.) It may help to use a large muck bucket with a towel placed on the bottom to provide more secure footing for the horse. For the best results, try placing the horse’s foot in the bucket, then fill it with water to just above the injured area, then add the ice.

If an ice bucket won’t work for your horse, try a more “targeted” approach. “Some horses do better with commercial ice boots or cold-water soaking boots you can strap on the
lower leg, since they can move around while wearing them,” says Allen. “Boots with pockets you can put ice into are also handy and fairly comfortable for the horse. There is usually something between the ice and the horse’s skin. The cold seeps through, but it doesn’t give the horse such an initial cold shock like putting the foot into an ice slurry.”

Cold packs can work, even if they are unconventional. “I have one client who keeps a bunch of bags of frozen cranberries in her freezer,” says Allen. “Whenever she has a situation where a horse needs an ice pack, she just tapes these on. They stay frozen/cold for about 20 to 30 minutes, which is as long as you’d need an ice pack. Then she refreezes them for next time.”

“Human athletes often take a frozen ice cup and massage the injured area,” says Seabaugh. “It is certainly useful in humans, but it may be more difficult to obtain results in horses with their thicker muscles. Ice packs over a certain area that gets sore after performance might be useful, however.”

If you’ll be using cold therapy often or want to be more certain that you’ll cool the target area enough, it might make sense to invest in one of the higher-tech systems for cooling limbs, such as saltwater “spas” and compression boots with continuously circulating fluids that cool the limb without getting it wet. “Many of the three-day event barns and some of the major training facilities have equipment like this to help with the recovery of equine athletes,” says Seabaugh. Horses typically become acclimated to their use and will stand quietly for, and even appear to enjoy, regular treatments. 

For better or worse, most of us are always ready to embrace innovative methods of caring for our horses. We aren’t daunted by new or complex techniques so long as there is the promise that they will benefit our horses. Sometimes, however, simple is good. And cold therapy, when applied properly, is just that---a good, simple
way to help keep horses sound, comfortable and healthy.

This article first appeared in EQUUS issue #457, October 2015.