Sleep Cycles
Understand Your Sleep & Wake Up Fresh

Time Spinning Clock

Sleep cycles are universal. We all sleep the same way and isn't that complicated.

But by taking the time to understand how we actually sleep, you might find it much easier to wake up in the morning.

A typical sleep cycle last around 90 to 110 minutes so during one single night we go through several cycles. And each cycle consists of several different stages which has its own characteristics. That's what I will explain here today.

But first, I just want to mention that we can separate the types of sleep into two distinct types - REM and NREM. REM is short for Rapid Eye Movement while NRAM simply means Non Rapid Eye Movement. NREM is then subdivided into several separate states.

So let's get into the steps of each sleep cycle.

NREM Stage 1 - Sleepiness

This stage is when you are beginning to fall asleep. Basically, you are not fully asleep, but also not fully awake. If you wake someone up during this stage, they might not even have noticed that they drifted off. The muscles are still active during this stage as well.

NREM Stage 2 - Light Sleep

By this stage, you are sleeping fully. You are not easy to wake up and you are muscles are relaxed.

NREM Stage 3 & 4 - Deep Sleep

This stage is usually referred to as deep sleep or delta sleep. As you might have guessed, you are not affected by external events anymore and are sleeping quite heavily. Also note that what was previously called stage 3 and 4 is now usually merged into one single stage.

During this stage is when your dreaming occurs and it usually accounts for around 25% of your total sleep time.

REM - Dreaming

The name REM was coined in 1953 after observations of a specific pattern of brain signals during this stage. All your muscles are paralyzed, except for a certain muscles in your eyes, hence the name rapid eye movement sleep. REM sleep is reached once every cycle after around 90 to 110 minutes as mentioned earlier.

So during the night you go through these phases in cycle after cycle. But the order it all happens is a little bit different than you might have imagined. Take a look at this hypnogram showing the stages of sleep during a night. During the second half of the night, it's quite common to actually not reach the deep sleep stage anymore.

Sleep Hypnogram

But I'm not going to go into detail about your entire sleep. What I want to mention now is how you can use this knowledge.

The absolute best time to wake up if you want to feel relaxed and fresh is during the shift from one sleep cycle to another. These happen at about every 90 minutes and are the time when you are very easy to wake up. I mean, wouldn't it be great if you just felt energetic to start a new day as soon as you open your eyes in the morning?

How The Sleep Cycles Will Help You Wake Up

So now then to the real important question, how can you make sure that you wake up at one of these times?

The best method I know is to from a habit of waking up at the same time. If you every single day of the week (yes, that includes weekends) wake up at, say 6.00 a.m., then after quite a short while will your sleep cycles start to adapt to this scenario. You will feel tired in the evening at around the same time and you will also fall asleep at a time that makes it possible to fit a certain number of complete sleep cycles during a full night.

That's how your body works. So my best advice is to form a very strong habit.

Some other people might suggest that you should count backwards from the time you wish to wake up. So 6.00 a.m. and 5 sleep cycles of 90 minutes each would provide you with 10.30 p.m. as your sleeping time. But what about if you’re not feeling sleepy at that time?

That's exactly why this approach usually doesn't work very well. But by having a habit you will soon see that you start to feel sleepy at the same time every single evening. And you will also start to wake up 5 minutes before your alarm clock - all fresh and ready for a new day!

So now you hopefully know how your sleep cycles work so make sure you use it to your benefit.

Early Riser > How To Wake Up > Sleep Cycles

Thanks for reading! By Matthew M. McEwan

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