If you're someone who only measures the total hours of sleep you get each night, it's time to revolutionize your thinking. It's far more beneficial to understand sleep cycles. Your goal should be to get a certain amount of deep sleep per night.
In this article, we cover the science of sleep stages and your circadian rhythm. We’ll be covering what deep sleep really is, and how much of it you need to improve your overall health. Plus, we provide pointers to teach you how to fall into a deep sleep.
Ready to get more deep sleep? Consider these tips to help you get started.
1. Set a Schedule
To get the necessary amounts of deep sleep, plan ahead and get enough rest each night. There's no way to cut back on light sleep and replace it with deep sleep. You simply need to allow your body to complete five to six complete sleep cycles each night to ensure you're receiving enough rest.
We recommend developing a bedtime routine and improving sleep hygiene, too. Choosing a few nighttime activities to help you wind down sets the tone that it’s time for rest. These can include a warm shower, relaxation techniques, or reading a book. Once you devise a routine, stick with it as best as you can— this will, over time, improve your overall sleeping habits.
Recent studies suggest daily cardio can increase or consolidate deep sleep. Try building time into your day for aerobic exercise, such as:
If you want to use exercise to improve your night’s sleep, just remember to time your workout right. Exercising in the hours before bedtime can impede sleep, causing you to doze off later in the night. However, early morning workouts have been shown to reduce sleep latency and facilitate deeper stages of rest.
3. Reduce Screen Time Before Bed
Blue light impedes melatonin production and delays your circadian rhythm. Staring at a screen in the hours before bedtime can result in serious sleep troubles, from not being able to fall asleep at all, to not being able to enter deeper stages of rest.
To get the best sleep, cut out blue light at least an hour before bed time. If you absolutely must use technology in that time, make sure you’re utilizing the blue light blocker function— known in most devices as “Night Mode.”
4. Keep Your Bedroom Conducive for Sleep
Your bedroom should be conducive for sleep and free from distractions. Many sleep specialists recommend investing in blackout curtains to block out the sun, and setting your thermostat anywhere between 60 and 67 degrees Fahrenheit.
If your room is too cold or too warm, it’ll cause you to wake up uncomfortable. But research has shown temperatures between 60 and 67 degrees promote deeper, more undisturbed sleep. You can also use fans and bedding to help you get cooler or warmer.
Keep your bedroom technology-free, especially if the device emits blue-light. Leave your phone in another room and turn off the TV at least an hour before bed. Your bedroom should be designated for sleep and sleep alone, and distractions can weaken your brain’s association between the two. The only electronics you should be utilizing while at rest are sleep trackers and alarm clocks, and even those aren’t necessary.
5. Take a Hot Shower
When you sleep, your body temperature decreases. One way to jump-start your circadian rhythm is by taking a hot shower before bed. When you take a hot shower, your body temperature spikes. But as soon as you step out of the shower, your body temperature drops. This initial drop in temperature facilitates the following drop in temperature your body needs to produce melatonin and drift off to sleep.
While cold showers do decrease your core body temperature, they can actually impede sleep. If you prefer cold showers, save them for the morning. Cold showers activate your sympathetic nervous system, responsible for your “fight or flight” functions, and stimulate both your mind and body. Many describe cold showers as “energizing,” and you likely aren’t aiming to feel energized right before bed.
What Is Deep Sleep?
Your body has an internal clock known as a circadian rhythm; this controls when you wake up and when you fall asleep. Although our circadian rhythm occurs naturally, some external forces can throw it off, such as exposure to blue light before bed.
While you rest, you go through different stages of sleep. Varying types of brain waves mark the differences between one sleep stage and another. You can categorize each stage of sleep as "non-REM" and "REM" sleep.
REM stands for rapid eye movement. Stages 1-3 are non-REM stages, while stage 4 is REM sleep. A complete cycle takes approximately 90 minutes.
Below, we discuss the differences between each stage of sleep.
- Stage 1 — This is the first stage of sleep when you start to drift off. Although your eyes are closed, it's easy to wake up since this is a light sleep stage. During this slow-wave sleep stage, our brain activity and eye movements begin to slow.
- Stage 2 — We move toward deeper sleep during this stage. Waking up is much more challenging. Brain activity slows, although there are specific bursts of activity known as sleep spindles.
- Stage 3 (Deep Sleep) — During this stage of deep sleep, brain activity consists of long-length delta waves. During delta sleep, it's tough to wake up. When we use the term “deep sleep,” this is the stage we are referring to.
- Stage 4 (REM Sleep) — Brain activity spikes and rapid eye movement occurs during this stage as you begin dreaming. It's easier to wake up during this stage, although you'll likely feel groggy or tired.
Why Is Deep Sleep Important?
Many people believe REM sleep is the most crucial stage of the nightly cycle, but scientists are realizing deep, Stage 3, sleep is just as important— if not more so.
Psychology Today says deep sleep is "a time of nearly complete disengagement from the environment." During this time, your body releases human growth hormone (HGH). HGH is an essential component of cell repair, allowing your body to recover. It helps:
- Strengthen your immune system
- Repair tissues and bones
- Increase blood supply
Researchers also believe deep sleep is the most refreshing part of the sleep cycle. Spending enough time in the third stage of sleep leaves you feeling recharged the next day. Additionally, your brain refreshes itself during deep sleep— preparing itself for a new day of learning and activities ahead.
- Heart disease
- Alzheimer's disease
If you want to wake up feeling more well-rested, tap into your sleep cycle and get the right amount of deep sleep each night.
How Much Deep Sleep Do You Need Per Night?
Too often, people incorrectly measure their sleep by how many hours they get per night. It's better to measure sleep in both the number of cycles completed and the quality of the rest you get while in these cycles.
As mentioned, a sleep cycle takes, on average, 90 minutes to complete. The actual length of a sleep cycle can vary from person to person, but we'll use that as the baseline for this example. Using this number, five cycles would take 7.5 hours to complete.
However, the accepted baseline total sleep time is 8 hours per night. If you were to get 8 hours though, you'd be waking up in the middle of Stage 2 or Stage 3. You'd find yourself feeling exhausted and groggy.
You'd be better off waking up after the completion of the fifth sleep cycle. Even though the actual amount of time spent sleeping is less than 8 hours, you'll find yourself feeling much more refreshed and rejuvenated in the morning than if you were to fall back asleep for another thirty minutes.
Although you should measure sleep in cycles, there are some benchmarks you can strive to achieve in terms of deep sleep. The New Health Advisor recommends adults older than 18 get about 1.5 to 1.8 hours of deep sleep her night. If you're looking for a good night's rest with adequate deep sleep, you'll want to complete five to six full cycles per night— equaling 7.5 to 9 hours of shut-eye.
Once you determine how much sleep you should get, you can set an appropriate bedtime based upon when you need to wake up.
Get a Better Night's Sleep
If you find yourself with sleep troubles or waking up tired each morning, reflect upon your sleeping habits. How much sleep are you usually getting each night? Are you allowing yourself to complete each sleep cycle, or are you waking up in the middle of Stage 2?
Simply looking at when you fall asleep and when you wake up each day can highlight areas for improvement. But if that’s not enough, utilize some of our tips for better sleep to get deeper, more restorative shut-eye.
Lastly, if you’ve tried every trick of the trade to get better sleep, consider replacing your mattress. A lumpy, unsuitable, or uncomfortable mattress can counteract any efforts towards better sleep and leave you feeling grumpy and groggy in the mornings.