Whether you’re an avid reader or simply enthusiastic about wellness, you must have stumbled upon numerous articles recommending getting adequate sleep. However, the one thing that most of these publications fail to underscore is that sleep occurs in various phases, and each stage provides certain benefits for our overall health and well-being. Deep sleep is one of the various sleep phases.
But exactly what does it mean to be in deep sleep?
This article shall answer that question before delving into the benefits of deep sleep and common behaviors you can practice getting a restorative night’s rest.
What Are The Different Stages of Sleep?
The best way to understand what constitutes deep sleep is to begin by introducing all the sleep phases.
Now, the sleep cycle falls into two main categories. They include Non-rapid Eye Movement (NREM) Sleep (also known as quiet sleep) and Rapid Eye Movement (REM) Sleep (also called active sleep).
As the name rightfully suggests, REM sleep is a phase during sleep characterized by rapid, uncontrollable movements of the eyeballs within the sockets. Experts assert that REM is the stage during sleep when the mind is fully awake. That explains its nickname – active sleep.
In contrast, the body usually goes into a state of atonia (temporary loss of muscle control) during REM sleep. The only muscles that remain vividly active are those that control eye movements and breathing.
Most dreams also occur during REM sleep. And as you may have guessed, this sleep phase tends to get more pronounced when approaching dawn.
Non-rapid eye movement sleep is the exact opposite of REM sleep. There are no rapid eye movements or heightened brain activities during NREM sleep.
NREM sleep further falls into three subcategories, namely;
1. NREM Stage 1 (N1)
NREM Stage 1 is the first sleep phase, when you begin to drift off to sleep. This stage typically lasts about 2 – 10 minutes, although the actual duration will ultimately depend on your sleep latency.
2. NREM Stage 2 (N2)
NREM Stage 2 quickly follows NREM Stage 1. It lasts about 20 minutes per cycle and is marked by a gradual reduction in consciousness.
Body temperature, breathing pattern, muscle activity, and heart rate also reduce further as you slip into N2.
3. NREM Stage 3 (N3)
NREM Stage 3 is the final phase of NREM sleep, coming right before the onset of REM sleep. N3 lasts anywhere from 20 to 40 minutes per sleep cycle.
Most importantly, NREM Stage 3 is the sleep phase that constitutes deep sleep. A person in N3 sleep is very difficult to awaken.
More About Deep Sleep and Its Benefits
Deep sleep, as the name rightfully implies, is the most restful sleep phase. But it’s what happens during NREM Stage 3 that makes it arguably the most significant sleep phase.
Muscles get more relaxed during N3 compared to N2 and N1. The relaxation cuts across all muscles in the body, including those that control eye movements and breathing, which tend to be rather active during REM sleep.
Muscle relaxation, coupled with slow breathing during sleep, provides several benefits. Most notably, it prevents physiological arousal that might result from pain, inflammation, or stiffness.
NREM Stage 3 is also the sleep phase, with the slowest brain waves ever recorded in human beings. These waves are known as delta waves.
Delta waves are more common in infants and young children. That essentially means children spend more time in deep sleep than adults.
Research has shown that delta waves may provide immense restorative benefits. These waves play a role in improving thinking abilities and solving complex learning problems. They’ve also been linked to an ability to escalate recovery from brain injuries and treat cognitive problems like attention deficit hyperactivity disorder (ADHD).
It’s also while in deep sleep that the brain’s pituitary glands release growth hormones. These hormones are responsible for increasing our height. They also have restorative effects and may help in the repair of damaged muscles, tissues, and bones.
Some research also points to a role of deep sleep in regulating glucose metabolism.
Ever wondered why many experts associate poor sleeping habits with weight gain? Well, it turns out that sleep deprivation impairs the body’s ability to expend glucose.
A build-up of excess glucose in the blood and without enough mechanism to get rid of these molecules may cause the body to store them in tissues as fat.
Last but not least, deep sleep is involved in memory consolidation. N3 plays such a crucial role in memory consolidation that it’s sometimes known as “sleep-dependent memory processing.” More specifically, deep sleep affects spatial declarative memory, in which short-term memories are consolidated into long-term memories via repetition.
Tips for Restorative Sleep
1. Follow a Routine
Consistency plays a key role in promoting a healthy sleep cycle. Therefore, endeavor to go to bed around the same time every day.
Now, maintaining regular sleeping hours may be understandably difficult for shift workers.
However, you can make up for that by sleeping the recommended number of hours every 24 hours. That’s 7 – 9 hours for adults and up to 16 hours for infants.
2. Mind Your Late-night Diet
There’s a reason nutritionists recommend eating a heavy breakfast but having a light dinner.
Overeating can lead to bloating, constipation, and/or diarrhea. The resultant discomfort and frequent bathroom visits can make sleeping for longer hour blocks difficult.
It’s also vital to avoid diuretics like caffeine and alcohol at bedtime. The exception is if you’re on a prescription for diuretic drugs.
3. Make Your Bedroom Comfortable
The easiest way to experience sleep disruptions is to sleep in an uncomfortable bedroom. Many environmental factors, such as bright lights and noisy appliances, can easily cause frequent sleep disruptions.
Therefore, ensure your bedroom is quiet, dark, and mentally appealing. This may need you to remove all computers, televisions, and smartphones from the room.
You might also consider investing in soundproofing curtains to block off excessive outdoor sounds and lights from getting into your bedroom. Soundproofing drapes are especially recommended if you live in noisy neighborhoods.
4. Get Some Exercise
Exercising a couple of hours before going to bed (preferably two hours earlier) can elevate your core body temperature, signaling your body to be awake.
But after about 90 minutes, your body temperature will begin to fall in readiness for bedtime.
According to Johns Hopkins Medicine, this is one of the many ways exercise might impact your sleep quality.
Wrap Up
Deep sleep provides numerous restorative benefits for children and adults alike. It’s even more reassuring to know that you can improve your sleep quality using certain natural interventions.
