Is it too hot to ride your horse?
Heat and humidity are the weather signatures of summer, but sometimes things get out of hand, and it becomes too hot to ride your horse. While horses and humans can sweat to dissipate their body heat safely, it’s sometimes not enough. There may be other factors at work, too, like the intensity of exercise and your horse’s sweating tendencies. Overheating is a real for some horses in summer.
Use temperature plus humidity as a starting point.
- As a very general rule, you can gauge if it’s too hot to ride by adding the actual temperature to the percent of humidity. For a 90 degree day with 85 percent humidity, the total is 175, not to mention a crazy, frizzy hair day.
- Here’s where things get muddy. What is the magic number? It depends. I found so many articles about this topic, each with a different magic number. It might be 140, 150, 180, or above. Generally speaking, the hotter and more humid the weather becomes, the more cautious you should be.
- Humid weather can raise a horse’s temperature because the water in the air prevents the sweat on your horse’s skin from evaporating effectively. When looking for that magic number, consider the humidity more than you would the temperature.
Not a huge fan of this nonsense. Time to skip riding.
The FEI has a different way to measure things
- Sometimes, the “temp + humidity” trick will steer you wrong. So, the FEI started measuring the “hotness” while prepping for the Olympics in 1986. They use a gauge to measure temperature, humidity, solar radiation, and wind. Here’s what the gauge does:
“The WBGT Index The only validated heat index for equestrian sport is the WBGT index3 . This was developed primarily for management of the three-day event cross-country at the Atlanta 1996 Olympic Games but was also used in Athens 2004 and Beijing 2008. An FEI project to refine the guidelines based on the WBGT for Eventing, Dressage and Jumping is currently in progress. The WBGT index is a single “temperature” that takes into account the effects of air temperature, humidity, sun and wind all at the same time. It is calculated from a measurement of Wet Bulb temperature and a measurement of the temperature inside a black globe (Figure 1). Alternatively, it can be measured with an inexpensive (~US$160; £120; €140) handheld device such as the ExTech HT30 which is widely available (Figure 2). The WBGT index = 0.7 x Wet Bulb Temperature (°C) + 0.3 x Black Globe Temperature (°C) Why do we use the WBGT Index? The WBGT Index is used because although it’s only one number, it accurately weighs up all the factors that determine thermal environmental load. It is also easy to measure with simple and inexpensive equipment such as the ExTech HT30 “
- Do we have access to this gauge? Usually not – so we need to use common sense and look at the big picture of things.
Other factors that contribute to your decision to ride, or not.
Your horse’s fitness level.
- The high-performance sport horse ridden six days a week at top levels can usually cope with heat much easier than the weekend warrior horse that is sedentary all week and then worked on the weekends.
- A horse’s fitness level can be measured and tracked over time using vital signs. This includes your horse’s temperature, heart rate, and respiratory rate. You can measure vital signs before you ride, in the middle of your ride, and at the immediate end of the exercise. Then take vital signs every five minutes until your horse’s vitals return to normal.
- As a horse gains fitness from month to month, his vital signs during exercise will lower, and his recovery rate will shorten. Your horse will also be better equipped to work for more minutes of moderate-intensity exercise.
The intensity of your horse’s exercise.
- You may be able to modify your horse’s exercise in hot, humid conditions. No need to gallop cross country, how about a trail ride instead? If you are lucky, you could find a creek and enjoy some cool water splashing around.
Your horse’s health issues.
- A younger horse with a clean bill of health will cool down easier than a horse with health problems. This is especially true for horses with heaves or allergies, which interfere with breathing. While there is not a lot of heat loss due to respiration, there is some. Heaves and some allergies create stress on the respiratory system.
A foamy horse does not mean he’s overworked or overheated. It means the latherin protein in the sweat was rubbed, creating foam.
Your horse’s sweating patterns.
- In the case of anhidrosis, there’s a direct line between the lack of sweating and overheating. Anhidrosis occurs when sweating doesn’t happen at all, or a horse is sweating in smaller amounts. This is particularly dangerous in hot and humid weather, as the horse can’t cool down with sweat. There is a high risk of overheating.
- On the other hand, too much sweat can be a problem, too. That blasted humidity traps moisture on the skin, and your horse may respond by sweating more. Horse sweat is unique because it’s a lot of fluids, but it’s also chock full of salt and other electrolytes. Too much sweat will create dehydration and upsets your horse’s vital mineral levels. Humidity just makes everything worse.
- Thanks to some brilliant horse-stuff manufacturers, you can get cooling blankets for your horse. Perfect for cooling down after a ride. (links to shopping down below)
Is your horse already a bit dehydrated?
- Check his vital signs. Temperature, pulse, respirations, and even digital pulses as you are grooming your horse. Above normal vital signs tells you that his body is working hard already to overcome the heat and humidity. It’s always a good idea to check in with your vet, just in case.
- To monitor hydration levels, check his gums. They should feel slippery, not sticky or dry. Anything other than slick is a sign of dehydration.
- You may notice that his gums have changed colors; that’s also a sign that things can go sideways. Pale pink gums are the norm; any other color like hot pink, purple, red, or even shades approaching blue are a sign to call your vet.
Your horse’s weight.
- If your horse is a bit chubby or even downright fat, he’ll have a terrible time trying to regulate his temperature with the extra weight. That extra insulation traps heat and may help bring a horse’s temperature to dangerous levels. Overweight horses may also tax their cardiovascular systems more. Read more about the overweight horse here.
Your farm’s amenities.
- Are you riding outside in the blazing sun, or is the arena covered and nicely ventilated? Are their shaded round pens or paddocks that your horse could exercise in instead of the sun?
- Sure, you have a hose and a cross tie for a cold water shower after a workout, but is it shaded? Or do you have access to a ventilated area with shade? What about fans? While cool water is helpful when your horse is hot, adding a fan boosts the evaporative cooling. His body will thank you when he can chill in some breezy shade.
This is my horse’s normal sweat pattern for a hot-ish day.
The time of day.
- I love to start my day early – so I can ride before things heat up. The mornings tend to have cooler temperatures, and if you’re lucky the bugs will still be asleep. Twilight or later is also a great time, beat the heat by going early or late! High noon is asking for trouble.
How long has your horse been in the hot, hot climate?
- Acclimation to temperatures and humidity levels takes time. Hot humid weather isn’t the norm for all horses. If you live in Canada and travel to Florida for the winter, you will leave the icy cold and arrive in a sauna.
- Don’t forget about crazy weather changes that bring weirdly hot days. There is nothing wrong with taking a few days off from riding and exercise to get through the heatwave.
How are your horse’s diet and drinking habits?
- If you even suspect your horse will be sweating, feed electrolytes beforehand. For all-day sweating and non-stop heat, refresh those electrolytes in the afternoon too.
- Because dehydration is possible, tempt your horse to drink as much as possible. Ideally, you already know what your horse likes mixed with his water. You can try adding apple or fruit juice, a tablespoon of his favorite feed, or even a sports drink. Always offer flavored water alongside unflavored water in case your horse is feeling picky.
- Add water to your horse’s meals. Soak hay for a few minutes and turn feed meals into more of a mush.
Is your horse overheated?
- The sure-fire way to know if your horse is overheated is to take his temperature. Now, you may come back from riding, and he’s his temp is above normal. He needs to trend back down towards his normal body temp. Check every five minutes.
Other signs of overheating include:
- Gum discoloration
- Abnormal vital signs
- Sweat that is sticky and thick
- A previously sweating horse stops sweating
- Acting depressed and lethargic
Call the vet. Don’t wait, don’t check the internet, don’t grab lunch, call the vet.
For the love of all things horse, use a thermometer for your guy.
What to do if your horse is getting overheated.
- Do not feed electrolytes. His body is already unbalanced. This can make it worse. Electrolytes should be given before exercise or when your horse will be sweating.
- Do not force any water into his mouth. If he wants to drink, he can. You may want to provide super fresh water.
- Do not give any medications.
Your vet can give you exact instructions to follow. This may include dousing with water and using fans. Some treatments can actually make matters worse, so rely on your vet’s plan. Play it safe when in doubt and talk to your veterinarian about what is best for your horse.
If you want to quickly shop for TPR tools to take your horse’s vital signs, you can click these links. As an Amazon Associate, I earn from qualifying purchases, which are not a penny more for you. I couldn’t be more grateful for your support!