How Horses Sleep: A Closer Look

Horses can experience three distinct phases of sleep.

They may be drowsy, in a state known as Slow Wave Sleep (SWS), or Deep Sleep during Rapid Eye Movement (REM) sleep.

Horses require at least 30 minutes to 2 hours of deep REM sleep daily to maintain their health.

Horses experience various stages of sleep just like humans.

However, their sleep patterns and habits are unique.

Last update on 2025-05-19 / Affiliate links / Images from Amazon Product Advertising API

Here are the critical stages of sleep in horses:

• Drowsiness: This is the stage where the horse is half awake and half asleep. They usually stand with their heads lowered and eyes half-closed, appearing very relaxed.
• Light sleep (Slow-wave sleep): During this phase, horses often stand up. Their muscles are relaxed, but they can move quickly if necessary. This is the most common sleep stage for horses and can last several hours throughout the day and night.
• Deep sleep (REM sleep): This is the stage where horses achieve their deepest sleep when dreaming occurs. Horses need to lie down to reach this stage of sleep because their muscles relax entirely. This stage is crucial for their overall health and well-being, but it usually lasts only for short periods, typically around 3-4 hours over 24 hours.
• Awake: Horses are awake for the majority of the day and night. They are either eating, interacting with their surroundings, or standing relaxed.

Each stage is essential for a horse’s overall health and well-being.

Lack of background, especially REM sleep, can lead to health and behavioral issues.

How Horses Sleep – Deep Sleep

When it comes to sleeping, humans and animals experience various rest stages. We doze off, experience Slow-Wave Sleep (SWS), and then need REM sleep to dream.

Horses also go through this cycle of rest, though not every horse has the opportunity to complete all the different phases.

Many horses require at least 20 to 30 minutes of sleep each night, even when safely resting in their stables.

During this period, blood pressure and heart rate usually slow down, and human growth hormone is released, aiding bone and muscle repair.

Horses also need deep, restorative REM sleep to function optimally day and night. Unfortunately, just like humans, horses only have access to this deep form of rest when lying down.

To achieve this, horses must lie in either sternal or lateral recumbency with their muzzles resting on the ground.

This position is necessary because during rapid eye movement (REM) sleep, horses lose all muscle tone and will collapse if standing up.

Though it may sound scary, REM sleep is integral to a horse’s life. Without it, they won’t be able to function normally.

Sleep is essential for horses’ performance and overall well-being.

Not only does it improve memory and learning abilities, but it also helps prevent diabetes and obesity, boost physical energy levels, and strengthen the immune system—and it can also boost performance levels!

Without enough deep, restorative REM sleep, stress levels can skyrocket.

This could lead to various issues, such as depression and anxiety, fatigue, decreased coordination, balance issues, and difficulty making decisions.

If your horse refuses to sleep, consult a veterinarian immediately to identify the source. It could be a minor injury or a more serious medical issue.

Last update on 2025-05-19 / Affiliate links / Images from Amazon Product Advertising API

How Horses Sleep – REM Sleep

REM sleep is an integral part of a horse’s nightly rest. It helps the brain recover from the day’s stresses and prepare for future activities.

Studies have even discovered that REM sleep can improve athletic performance, speed of reaction time, and cognitive function.

The duration of each REM stage varies between individuals and is affected by several factors, including age, recent sleep patterns, alcohol consumption, and other environmental influences.

These factors can influence how much REM sleep a person experiences.

For instance, a young child may require more REM sleep than an adult due to their increased focus and concentration during this stage.

Newborns also tend to have more extended REM periods than older individuals and may enter them immediately after falling asleep.

Horses can drift off to a light sleep while standing but cannot achieve deep rest due to a complex system of bones, muscles, and ligaments known as the stay apparatus.

Standing allows them to drift off into light sleep, but they cannot get the rest they require for optimal well-being.

During this stage, the horse’s body temperature drops, its heart rate slows, and muscles relax. Their brain waves become synchronized and appear to “drift off.”

However, this can be dangerous if a horse does not sleep. If they enter REM sleep while standing, their muscles relax and may collapse from the associated muscle relaxation.

Another issue with REM sleep for horses is that it may lead to paralysis. This is especially common in horses with chronic orthopedic disease and could result in serious injuries.

Horses with chronic orthopedic diseases may also be more vulnerable to other health issues and neuroses.

These horses may have difficulty adapting to their environment, leading them to stop sleeping when feeling uneasy or threatened by something in the vicinity.

Monitoring horses’ sleep patterns and being alert for signs of sleep deprivation is essential. These could include decreased REM sleep, lack of energy and mental alertness during the day, and poor performance.

How Horses Sleep – Snoozing

Snoozing is an automatic sleep pattern for many horses. It’s how they unwind from a long day, and often, it’s their only chance to stretch out on their own in safety.

When a horse is dozing, its head lowers (midway or slightly), its eyes may close (or slow blink) occasionally, and its lips relax and droop.

Dozing often occurs during activities like grooming or being left alone at the crossties while you clean stalls.

Horses typically take short naps, lasting 15 minutes at a time. While horses may also doze off during the day, they commonly doze more at night.

When horses nap, they typically lie down and relax on the ground. This is the best way for them to achieve deep REM sleep – which they need for optimal health and alertness.

However, if a horse cannot lie down safely due to an impending thunderstorm or feeling unsettled, they may doze off in more sedentary positions instead.

They can doze off while standing, but this is a risky and uncomfortable position for them; thus, lying down allows them to fully relax and enter a deep sleep state.

Most studies of equine sleep only measure it overnight, which presents a challenge since this doesn’t accurately reflect a horse’s overall cycle.

Many studies lack enough data to compare with human equivalent sleep cycles.

Factors such as diet, temperature, workload, and gestation can also impact a horse’s sleep quality and quantity.

Horse owners must record their horses’ sleeping patterns to ensure their animals get enough rest. Changes to routine, such as moving to a new barn or placing lights while riding, can also affect these cycles.

But even when these changes happen, horses are highly adaptable; they quickly adapt to their new environment and return to their regular sleeping patterns.

Horses’ night behaviors vary based on their environment, individual habits, and health.

Last update on 2025-05-19 / Affiliate links / Images from Amazon Product Advertising API

However, generally, here are a few things horses tend to do at night:

• Resting and Sleeping: Horses do sleep at night, but not in the same way as humans. They go through cycles of drowsiness, light sleep, and occasional deep sleep. Deep sleep typically occurs in short bursts; horses must lie down to achieve this.
• Eating: Horses are grazing animals and spend a lot of time eating, even at night. If they have access to food, they will often feed intermittently throughout the night.
• Standing or Lying Down: When not eating or sleeping, horses often spend time simply standing or lying down. They can rest while standing due to a particular arrangement of muscles and bones in their legs called the “stay apparatus.”
• Socializing: Horses are social creatures. If housed with other horses, they may spend part of the night interacting with their companions.
• Moving Around: Depending on the size of their enclosure, horses may move around during the night, either walking or trotting.

Remember, every horse is unique, and their nightly activities can vary.

Changes in their routine or behavior can also indicate health issues, so their caretakers must monitor them closely.