Deep sleep, also called slow-wave sleep, is a term used to define stage three and four of sleep. During these stages, your heart rate and breathing are at their lowest, your brain waves slow down, and your muscles and eyes relax. This is also known as the ‘restorative’ phase of sleep because your body repairs tissues and strengthens its immune system.
While you sleep, you experience different stages of the sleep cycle. Deep sleep is the stage needed to wake up feeling refreshed. As we get older, the amount of deep sleep we get each night decreases. This is because our bodies are already fully developed and we don’t need the same growth that children do.
To help quiet your mind and learn how to increase the amount of deep sleep you get each night, practice the tips below.
It’s no secret that getting in a daily sweat sesh is beneficial to sleep. Those who work out during the day tend to fall asleep faster than those who don’t work out at all. Researchers also found that those who work out 150 minutes a week are twice as likely to get a good night’s sleep. However, make sure to avoid intense workouts right before bed as these can raise your heart rate — leading to interrupted sleep.
A healthy diet does more than just improve weight loss, it also has an impact on the quality of sleep you get. Studies have shown that a greater intake of fiber can result in more time spent in the stage of deep sleep. During the day, make a conscious effort to add more fiber to your diet in addition to other foods that promote sleep.
Not only is yoga a great way to center your body and mind, but it can also promote better sleep quality. One study found that those who practiced cyclic meditation — an exercise that combines yoga poses with rest periods of lying on your back — were more likely to experience deep, slow wave sleep. Work yoga into your daily workout routine or right before bed. Focus on yoga poses for sleep that relax the body and mind.
Caffeine is a stimulant that can make it harder for you to fall and stay asleep. It also can reduce the amount of deep sleep you get. One study found that consuming caffeine seven hours before bedtime reduced the amount of sleep received by one hour. Stick to water, tea, and other decaffeinated drinks instead. Certain drinks such as warm milk and chamomile can help induce sleep.
An alcoholic drink before bed may help put you to sleep, however, it’s likely you won’t stay asleep. When you have a nightcap before bed, the alcohol gets processed by the body. The sedative effect it once had disappears and will often create a rebound effect — waking you up in the middle of the night and interrupting deep sleep. If cutting alcohol out of your nightly routine seems impossible, stick to drinking a glass earlier in the evening to avoid a wake up call at 3 AM.
Stress from a busy workday or taxing afternoon with the kids can make it difficult to shut your mind off and enjoy sleep. Creating a personalized bedtime routine can help your body relax and curb any looming sleep anxiety.
Your bedtime routine should be anywhere from 30 to 60 minutes and the key is to keep your routine consistent. This will help your mind associate the routine with sleep and set you up for a productive next day.
The environment where you lay your head each night should be sleep-friendly. That means no bright lights, no loud noises, and a cooler temperature. The best temperature for sleep is between 60 and 67 degrees Fahrenheit.
On your nightstand, use low, amber light bulbs and avoid using electronic devices at least an hour before bed. It’s also important to make sure you have a comfortable mattress that supports you when you sleep. Pair this with your favorite pillow and a plush comforter and you’ll be fast asleep in no time.
Sound plays an important role in your ability to fall and stay asleep. If you live in the heart of a city or have noisy neighbors, try using white noise to block any sound that may be keeping you from falling and staying asleep.
Those looking to increase deep sleep may benefit from listening to pink noise. Pink noise represents calming nature sounds like steady rainfall or waves crashing on a beach. This type of noise has been found to increase deep sleep and improve memory in older adults.
If you are the type of person that likes to doze off to music, add some binaural beats to your playlist. A binaural beat is when you hear a different tone in each ear that is slightly different in frequency. In order for a binaural beat to work, the tones have to be listened to separately through each ear and they have to have frequencies less than 1000 Hz.
Music is a great way to soothe your mind and body. To slip into a deep sleep, look for tracks with lower beats per minute. Tunes around 60 BPM include music composed of binaural beats. These types of beats have been associated with higher levels of deep sleep and relaxation.
Similar to sound, light also has a drastic effect on the quality of sleep you get each night. If you have a partner who likes to read with the light on or if you work night shifts and catch up on your zzz’s during the day, a sleep mask can help. One study found that the use of eye masks on participants resulted in more REM sleep and elevated melatonin levels.
So, what actually happens during deep sleep? To understand deep, slow wave sleep, it’s important to understand the sleep cycle as a whole. There are two phases of sleep: non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep.
When your brain first enters sleep, your mind travels through the three stages of NREM sleep and then goes through one stage of REM sleep. Once this cycle is repeated, the process repeats itself until you wake up. Below is a look into each stage of sleep.
Stage One
The sleep cycle begins with stage one where your body is just beginning to relax. People will often experience slow, rolling eye movements, sudden jerks or muscle spasms, or a sensation of falling. During this stage, you can easily be awoken.
Stage Two
During this stage, your slow eye movements will stop, your heartbeat will slow, and your body temperature will begin to drop. Your muscles will also begin to contract and relax as you drift deeper into sleep.
Stage Three
Stage three is where deep sleep occurs. During this stage of sleep, your brain waves slow down and become delta waves, making it much harder for you to be woken up. This stage is so important because it’s a restorative stage of sleep. It’s during this time that your body repairs and regrows tissues, strengthens its immune system, and builds bone and muscle.
Stage Four
The last stage of sleep is REM sleep — the deepest stage of sleep. During this time, your brain becomes more active by helping you form memories and experience vivid dreams. In this stage, your breathing, heart rate, and eye movements speed up and your blood pressure increases.
Deep sleep stages — REM sleep and stage three of the sleep cycle — are the most important stages of sleep. They are known as restorative phases that are critical for hormone regulation, growth, and physical renewal. REM sleep is also when the brain forms and stores information in a person’s long-term memory. It also helps boost feel-good chemicals like serotonin.
If you were to forgo deep sleep, it’s likely you would wake up feeling groggy and depressed. You may also gain weight and have difficulty concentrating and being social during the day. Deep sleep is not only important for the body and mind, but for your overall quality of life.
The average adult needs between 1.6 and 2.25 hours of deep sleep a night. Newborns and babies need around 2.4 to 3.6 hours of deep sleep; children ages one to five need around 2.2 to 2.8 hours of sleep; and teenagers need around 1.7 to 2 hours of deep sleep.
Sleep needs change as you age. The older you get, the less deep sleep your body requires, however, that does not make it any less important. While there is no specific requirement of how much deep sleep you should get, people who are younger generally need more as it promotes growth and development.
A good tell-tale sign you aren’t getting enough deep sleep is if you wake up feeling exhausted. When we don’t get enough deep sleep we wake up feeling groggy and lethargic. There are also different types of sleep technology that can help you track your sleep.
Sleep tracking apps such as the SleepScore app and the Sleep Cycle app can document your sleep and lifestyle habits. While these won’t magically improve the amount of deep sleep you get, they will provide insight into your sleep habits and help you identify areas where you can improve.
Deep sleep does wonders for the body and mind. Understanding how deep sleep works can help you identify ways you can increase it. First look at your lifestyle habits. If you aren’t making an effort to work out daily, start there. Just getting outside for a 30 minute walk can go a long way.
Of course, everyone is different. Some people may benefit more from adding yoga to their daily routine. Whatever it is, make sure you’re setting yourself up for a successful night’s sleep with a mattress type that’s right for your body and specific needs.