Mission Statement

Keeping our horses’ legs cool has always been our mission at Cryochaps. Therefore, we made it our aim to not only cool horses’ legs down after exercise but to also keep the leg as cool as possible during exercise

Why do the legs get so hot when the horses exercises?

 

Tendons produce heat. When we exercise our horses, the tendons in the lower leg act as coiled springs. As the hoof lands, the superficial digital flexor tendon (SDFT) is stretched as the fetlock joint hyperextends and sinks towards the ground. That stretch stores the energy until the hoof leaves the ground and the tendon elastically recoils, converting most of the stored energy back to kinetic energy, propelling the horse forward. The energy stored in the stretch is not all recoverable, and some 5–10% is released as heat. This is the reason our horses’ legs get so hot when we exercise

Insulating effect of boots and bandages

Boots and bandages are needed for protecting your horses legs. Some horses have a habit of striking into themselves and need a boot to protect the legs, or you may be doing a discipline where you are increasing the likelihood of impacts, like dressage and jumping. We have all taken boots and bandages off to find sweaty legs. So how hot do the legs get? Temperatures as high as 45°C have been recorded in the core of this tendon during gallop exercise, while the tendon surface temperature plateaued at 5°C lower, at 40°C (Wilson and Goodship, 1994).

Cryochaps have replicated similar results, using external temperature sensors placed over the middle of the tendon at the back of the leg, underneath a set of boots

What does this mean for our horses legs?

There is clear evidence from two unrelated studies that in the lab, these temperatures are seen to affect the survival of the tendon cells (Birch et al. 1997; Hosaka et al. 2006). After 10 minutes of heating at 45°C, the tendon cell survival fraction was 91%, whereas heating for 10 min at 48°C resulted in a drop in the cell survival fraction to 22%. The study concluded that while temperatures experienced in the central core of the SDFT in vivo are unlikely to result in tendon cell death, repeated hyperthermic insults may compromise cell metabolism of matrix components, resulting in tendon central core degeneration (Birch et al. 1997).

So why is Exoskeleton different?

The Exoskeleton exercise boots for horses uses a process known as forced convection cooling. As the leg moves forward through the flight phase, the horse’s tendons and ligaments relax, making an air gap at the back between the leg and the boot. This allows air to be forced over the back of the leg as it is channelled between the vents, cooling the rear of the leg where most heat build-up is created.

The spacer fabric covering the holes is used a lot in the medical and defence industry to reduce the heat build-up of our bodies. It allows the air to circulate through the boot, wicking away moisture but also providing cushioning to help with protection.

The Exoskeleton exercise boot provides superior patented ventilation, and as exercise intensity increases so does the convective cooling.

Results of test carried out and how temperatures rise with Exoskeleton (orange) versus a Market leading Vented Tendon Boot (MLTB) when the horse is asked to do 15mins or trot and canter followed by a 5 minute walk off

The ­first trot and canter show how the vented MLTB leg temps steadily rise over and above the Exoskeleton  – between blue circles

Walk – the leg temperatures initially rise and then plateau, as less air is being forced over the back of the leg as slower speed – between yellow circles

When the speed increases again there is a marked drop in temperature inside the Exoskeleton boot compared to vented MLTB as the air is being forced over the back  of the leg much more rapidly –  between green circles

Walk off – temperatures initially increase but then start to fall. The Exoskeleton enhances cooling, dropping the leg temperatures to the initial starting temperatures far more quickly than the MLTB as the heat can escape – between red circles

Exoskeleton maintains temperatures under 36.5 degrees, other boots the surface leg temperatures often rise as high as 39 degrees. This indicates that the core tendon temperatures could indeed be getting to levels as high as 45 °C if the external temperatures are at 39.

Having the exoskeleton armour opened up with large vents, also allows the heat to escape when walking off, so the heat is dispersed much quicker than other boots, limiting the time the internal temperatures are at high levels

We would always recommend removing tendon boots as quickly as you can after exercise and there is always a role for cooling the legs with ice boots for horses, such as Cryochaps, to help promote recovery after exercise.