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Why Do Horses Sleep Standing Up?

horse sleeping in the stable

You may have wondered why horses fall asleep on their feet. Can they really sleep while standing? Yes, they can.

Horses belong to the prey mammal category, meaning they are always at risk of attack from predators.  As an adaptive technique, they developed a feature called the stay apparatus, where the leg muscles, limbs, and ligaments interlock to provide stability even as they sleep. Other animals with this feature include huge land mammals like elephants, cattle, giraffes, and birds. Other than being targets to predators, these animals are huge, making them very conspicuous.

If they have to lie down every time they need sleep, they can easily be attacked. Sleeping while in a standing position enables them to take flight easily in the face of an ambush.

horse shoe divider new

Do Horses Require Sleep?

Good sleep is a vital part of animals’ overall well-being. They need quality rest for optimal mental and physical soundness. If you are constantly around horses, you will realize that they take a lot of naps during the day.

It is during these naps that they can sleep while standing. However, when they have to take a deep sleep, which they do for approximately three hours daily, they have to lie down properly. To sleep well while standing, they distribute the body weight in three limbs and allow one leg to rest. They can alternate the legs every so often so that all of them get to rest. Remember, they weigh as much as 1,500 pounds, making the ‘stay apparatus’ feature quite intriguing.

horse sleeping close up
Image Credit: vprotastchik, Shutterstock

Do Horses Get Deep Sleep?

As mentioned, horses, like any other land mammal, require deep sleep to function properly. While we need at least six hours of quality, deep sleep, horses only require at least two to three hours, and they’ll have fully replenished themselves. This quality sleep is referred to as REM sleep. The aim of deep sleep, also referred to as desynchronized or paradoxical sleep particularly helps develop the nervous system.

Horses can have a sleep in bits of 20 minutes each at night. This is the only time horse can get serious shut-eye while they lay down. They, however, need to have a safe environment for them to sleep.

This comes back to the idea of them being prey, and their instinct won’t let them rest easy. For example, a noisy vicinity makes them nervous, so you might want to turn down such triggers for them to rest easy. Environmental stress can affect your horses’ sleep time.

Another reason why your horse may not be sleeping could be because the stall space is small. This can make the horse feel trapped and unable to have a serious shut-eye. If possible, have them on separate stalls so that they can feel comfortable in their individual spaces.

Also, let them coordinate their sleeping pattern. It is not unusual to find one horse asleep while others are looking out for them. They continue turn-taking until all of them are well-rested. The wild lifestyle has not shed off completely, no wonder their resilience on survival tactics.

  • Tip: If you want the best results from your horse during training, you have to help them retain and create new memories. Helping them deep sleep is one such way.

Sleeping Patterns for Different Ages

Horses sleeping patterns vary with different ages and for different reasons. First, a fully grown horse requires only 2–3 hours of deep sleep in a day. This is despite the numerous naps they can take throughout the day.

On the other hand, Foals need more sleep, and they do get it since their mothers are always on the watch. They sleep a lot during the day for at least three months. During this time, they [foals] sleep for half the day. After that, they have to learn how to sleep while standing up and taking several naps during the day.

mare and foal sleeping
Image Credit: Anastasija Popova, Shutterstock

What Happens When a Horse Doesn’t Get REM Sleep?

If they do not get enough deep sleep, horses get stressed, irritable, and perform poorly.

There are also likely to display some discomfort despite having regular naps. So, other than physical issues, your horse will also have some mental impediments.

If you have enough land too, it can work to the horses’ advantage as they will have more touch with nature.



We can conclude that horses sleep while standing because they can. Even though they have been domesticated, their natural instinct is in the wild, hence the need to always protect themselves. When having intervals of light sleep, they can stand. For the deep one, they have to go down.

Featured Image Credit: Hanna Alandi, Shutterstock

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