How do horses sleep?

Whether or not you’re a horse owner, you may find the way horses sleep slightly strange.

After all, how does a horse avoid toppling over when they choose to snooze standing up? Why don’t horses always lie down to sleep? And how much sleep do horses need?

REM sleep in horses

REM stands for ‘rapid eye movement’, and it’s the type of sleep associated with dreaming and muscle relaxation. Even though scientists are still researching the importance of REM sleep, since it’s discovery in the 1950s, they believe this form of deep sleep helps with memory and learning in humans. Studies suggest that REM sleep is just as important for all mammals and birds, too.

 A key difference between us, though, is that horses only need around 30-60 minutes of REM sleep every day, which is less than humans need (about 25% of the time you spend sleeping should be REM sleep)! 

One of the main reasons horses need less REM sleep than humans is that horses can only achieve this state while lying down. It’s difficult for horses to spend much time lying down because, in the wild, they must be prepared to flee from predators.

Lying down is hard work for horses, too. Not only does it take a lot of effort for horses to stand after lying down, it’s also dangerous for horses to lie down for long periods of time (due to the damage it can cause to their organs).

Stay apparatus and check ligaments

The stay apparatus (the arrangement of muscles, tendons and ligaments that work together so that an animal can remain standing) of your horse’s legs help them to sleep safely while standing up. In your horse’s hind (back) legs, the stay apparatus is located within the stifle joint, and it locks their leg in place until they actively step forward.

Check ligaments are situated in your horse’s lower legs and take any strain off your horse’s muscles to allow them to sleep soundly.

Fun fact: Horses don’t have muscles below their knee and hock joints!

How long do horses sleep for?

Foals and older horses can sleep longer, though, in general, most horses sleep for just three hours a day!

If horses don’t get enough sleep, they’re at a greater risk of illness and injury. However, your equine best friend will only sleep if they feel safe. 

It’s important horses are comfortable in their environment, and that they’re happy to lie down when they’re tired. So, by keeping your noble steed’s stable inviting and their turnout situation safe, they’ll sleep better and feel healthier.

Herd habits

As a herd animal, your horse likely loves spending time with their herd! 

Your horse’s herd mates are more than just friends, however. While resting as a herd, one horse tends to ‘stand watch’ as the others enjoy a good sleep. The reason for this brave behaviour is instinctive to your horse, because they are a prey animal.

It doesn’t matter whether they live in a beautifully kept field or the rugged wilderness of a mountain, each horse in a herd will take their turn as guardian while others sleep by keeping an eye out for predators.

If you’re concerned about your horse’s sleeping habits, please contact your vet.