Why Do People Twitch in Their Sleep?

February 8, 2021 · Mattress Warehouse
twitch in sleep

It’s happened to a majority of us. You’re lying in bed, right at the cusp of falling asleep, when BAM! You are startled awake by the jolt of your arms and/or legs moving suddenly without you telling them to do so. What just happened? As you try to fall back asleep, you’re left to wonder – why do people twitch in their sleep?

Twitching in your sleep, also called hypnogogic jerks or hypnic jerks, affects up to 70 percent of people trying to sleep, according to research. While these contractions might sound scary, there’s no cause for concern.

Walter James, M.D., a sleep medicine physician at Piedmont Healthcare in Georgia, says these hypnic jerks or sleep starts are a totally normal phenomenon that is in no way harmful or an indication of underlying illness.

“Experiencing a hypnic jerk upon sleep onset can be compared to unplugging an electric appliance — sometimes you see a little spark,” says Dr. James. “In the same way, your muscles may experience an involuntary muscle spasm as your body transitions to a restful state.”

Still, why do people twitch in their sleep? There are a few trains of thought on the reasons why.

twitch in sleep

Top 5 Reasons People Twitch in Their Sleep

Anxiety and Stress

It seems like everything is caused by anxiety and stress, doesn’t it? Here’s another thing you can chalk up to being anxious before going to bed.

Anxiety and stress tend to keep your brain in an “active” mode while the rest of your body is trying to relax and call it a night. While your muscles are relaxed, your brain might send a message to your body that causes it to twitch, which causes you to be fully awake. As you try to fall asleep again, the process starts all over.

Of course, because anxiety loves to keep you awake, there’s a chance you might become anxious about the hypnic jerks, causing you to continue to twitch in your sleep.


It should come as no surprise that stimulants, such as caffeine and nicotine, will keep you awake at night. In fact, many people will drink coffee or smoke cigarettes just to stay awake. However, if you’re not trying to stay awake, drinking that soda or lighting up that smoke before going to bed will have the same effect on your brain as anxiety and stress.

Your body wants to sleep, but your caffeinated brain would like you stay awake for awhile and think about a million and a half things. Your muscles do their thing for the night, but your brain decides it’s time to wake your body up with a jolt just as you’re nodding off.

Sleep Deprivation

Sleep deprivation falls right into the same category as anxiety and stimulants when it comes to why people twitch in their sleep. Think of it this way – can you remember a time you were so utterly exhausted all you wanted to do was sleep, but once you got to bed, you couldn’t fall asleep for all the money in the world? There could be outside factors (any new parents out there?) causing the sleep deprivation, or it could just be your body and brain have decided not to work together.

You want to fall asleep so badly and your body agree with you, but your brain still has other ideas. That’s why sleep deprivation can also play into why people twitch in their sleep.


Surprise, even healthy things can cause you to twitch in your sleep! While of course exercise is good for you – and exercising at night can help you fall asleep faster – you also run the risk of overstimulating your brain, causing it to go haywire such as in the examples above.


You know, sometimes you can do everything right and you’ll still twitch in your sleep.

“They’re healthy people with a very unpleasant experience,” explains James K. Walsh, executive director and senior scientist at St. Luke’s Sleep Medicine and Research Center in St. Louis.

Genetics – and, to a certain degree, evolution – can explain why some people twitch in their sleep. The spasms could be an ancient primate reflex to the relaxation of muscles during the onset of sleep — the brain essentially misinterprets the relaxation as a sign that the sleeping primate is falling out of a tree, and causes the muscles to quickly react.

How to Stop Twitching in Your Sleep

Fortunately, there is no underlying medical reason for why people twitch in their sleep. There are a few ways to try and help prevent twitching in your sleep:

  • Try to relax as much as possible before going to bed.
  • Stay away from stimulants before bed.
  • Try to avoid exercise an hour before bedtime.
  • Stay as close to a regular sleep cycle as possible.

Another thing that might help is making sure you have the right mattress. An old, lumpy mattress might also keep you up at night, which can cause a variety of health issues.

At Mattress Warehouse, we don’t guess which mattress is best for you – we let science determine your best mattress. bedMATCH®, our patented diagnostic sleep system, can narrow your mattress search down to a handful of types and prices in minutes. And, with our Clean Shop Promise, it’s completely safe to visit any of our stores.