On average, light sleep will take up about 50 to 60 percent or more of your night. When you click on the sleep tile from your Fitbit dashboard and then choose Today, you’ll be able to see how much time you spent in each sleep stage and what percent of your total night’s sleep that stage constituted. “By the time the night’s halfway over, you’re done with it.”Ĭycle 2: You’ll get slightly more light sleep, still a lot of deep sleep (but less than before), and a little more REM.Ĭycle 3: You’ll probably log a lot more light sleep, a little bit of deep sleep, and more REM.Īfter this, during the second half of the night, the cycles mostly break down as your body alternates between light sleep and REM for the rest of the night. “It’s very hard to wake up from deep sleep, which is why your body tries to get it over with as quickly as possible,” says Grandner. Then you’ll move q uickly into deep sleep, where you’ll stay for a while before going into 10 minutes or so of REM. “Each cycle lasts, on average, 90 minutes,” says Grandner, “but some cycles can be as short as 50 minutes and some can be as long as 100 minutes or more.” Here, according to Grandner, is how it works:Ĭycle 1: During light sleep you’ll dip into stage one and transition into stage two. In fact, it cycles through all of these stages multiple times a night. Your body doesn’t just hit each sleep stage once a night, nor does it spend an equal amount of time in each of them. It’s also the peak of protein synthesis at the cellular level, which keeps many processes in the body working properly. REM is very important for emotion regulation and memory-you’re clearing the brain of things that aren’t needed, says Siebern. Heart rate increases and your breathing becomes more irregular. REM is when most dreaming happens and your eyes move rapidly in different directions (hence the name). Actually it’s so inactive, you’re actively paralyzed during REM sleep.” “The brain is very active during REM sleep, yet the body is very inactive. “If deep sleep is about body, REM is about the brain,” says Grandner. According to Siebern, deep sleep has also been shown to help strengthen your immune system. Your body is doing a lot of rebuilding and repairing.” Deep sleep is when your body secretes growth hormone, which is associated with cellular rebuilding and repair. You’re not dreaming at all during this time. “The thinking parts of the brain are largely offline. “Deep sleep is very much about the body,” says Grandner.

Breathing slows and muscles relax heart rate usually becomes more regular. Stage 3: During deep sleep, you become less responsive to outside stimuli. So there’s a lot of body maintenance occurring during lighter stages of sleep.” Breathing and heart rate typically decrease slightly during this stage. “It’s when your body processes memories and emotions and your metabolism regulates itself. “Light sleep is very important because it takes up more than half of the night,” says Grandner. That said, stage 2 sleep is not shallow, nor is it less important than other sleep stages.

Stage 2: When people talk about light sleep, this is the stage they’re usually referring to. “Your brain has dipped into sleep but you don’t feel like you’re asleep.” “But it’s usually just a quick transition, so you’re not in it for very long.ĭuring stage one, “you’re still hearing things and have a sense of awareness,” says Fitbit sleep consultant Allison Siebern, PhD, consulting assistant professor at The Stanford Center for Sleep Sciences and Medicine and director of Sleep Health Integrative Program at the Veterans Affairs Medical Center in Fayetteville, NC. Stage 1: “This is the sleep that’s a little more choppy, shallow, not restful,” says Michael Grandner, MD, director of the Sleep and Health Research Program at the University of Arizona in Tucson and a Fitbit sleep consultant. In the app, your sleep will fall into three stages: light, deep, and REM. Sleep researchers divide sleep into five stages-stages 1, 2, 3, and REM-but to keep things simple, Fitbit groups like sleep stages together. Below, a breakdown of what you need to know about each sleep stage. Pretty cool, right? Each of these stages-or sleep types-serve a different purpose, so understanding how much of each stage you log can help you identify and address sleep-related issues.

By tapping into your nighttime heart rate and movement patterns, these devices will be able to estimate how much time you spend in light, deep, and rapid eye movement (REM) sleep. Waking up tired, angry, or cranky? If you use a Fitbit Alta HR, Fitbit Charge 3, Fitbit Versa, Fitbit Ionic, or Charge 4, your sleep data may soon be able to reveal why.

Not getting enough deep sleep fitbit