YOUR 2025 BRAIN BRAWN MINI RESOLUTION SLEEP BETTER: WEEK 5

The Architecture of Sleep

 
Good morning! We hope our sleep tips are helping you wake up feeling primed and ready for the day.

 
CCP's Curated Sleep Tips

 
So far, we’ve discussed sleep pressure (the increasing pressure to sleep during the day determined by rising levels of our neurotransmitter adenosine), circadian rhythm (the daily sleep/wake cycles impacting all human physiology influenced by light exposure) and sleep debt (the difference between how much sleep you need vs. how much you get).
 
Now we would like to discuss another sleep topic: sleep architecture.
 
Theories abound but no one really knows why we sleep. What we do know is what happens physiologically to the body during sleep and how this impacts health and vitality.
 
Human sleep is characterized by a succession of sleep cycles. Within each sleep cycle are 4 stages. Within each stage, different physiological changes happen to recharge, restore and repair the body. Completing each stage and cycle fully is the key to sleep quality.
 
FUN FACT: Newborns and those with narcolepsy are the exceptions to the sleep stages rule. Newborns have three stages specific to their age, and narcoleptics spend very little time in earlier sleep stages and almost go straight to REM.

 
Sleep Stages

For the rest of us, one full sleep cycle runs about 90 minutes, and we go through about 4-6 sleep cycles per night. One full cycle consists of these four stages:

 
STAGE 1
Lasts about 7 minutes

This is your “nodding off” stage, where you are easily awakened.

You know that sensation of falling and being awoken with a start? That is called a Hypnic jerk and happens in Stage 1. Fun Fact: These involuntary, rapid muscular movements fall into the same family as hiccups, called myoclonus.

Brain plasticity begins. Brain plasticity is the ability of the brain to re-wire itself (i.e., learn and modify behavior and as we already know this is critical for avoiding cognitive decline!)

STAGE 2
 Lasts about 10-25 minutes

Still light sleep, but deeper than Stage 1.

Blood pressure and body temperature drops (recall how a hot bath causes a sudden drop in body temperature inducing sleepiness).

Muscles relax.

Memories are consolidated from short to long term, also critical for preventing cognitive decline!

 
STAGE 3
Lasts about 20-40 minutes
Termed "slow wave sleep" (SWS)

It is quite difficult to be awoken from Stage 3 sleep and if you are awoken, you will be very groggy and likely will suffer from sleep inertia.

Stage 3 is where much of the sleep “magic” happens. 

Stress hormones are reduced, also critical for preventing cognitive decline as these hormones can create oxidative stress in the brain.

Toxins washed from brain, also critical to prevent cognitive decline (Fun Fact: your brain swells during the day and at night it shrinks to its normal size through this glymphatic system process).

HGH and testosterone are secreted, encouraging tissue repair, muscle growth and development.

Immune cells are at peak levels improving immunity, also critical for preventing cognitive decline by protecting the blood/brain barrier.

STAGE 4
Lasts up to 4 minutes
known as the Rapid Eye Movement (REM) stage where dreaming occurs
 
This is when you achieve paradoxical sleep where the brain is very active, but the body is paralyzed so you don’t act out your dreams and injure yourself or others.

Here, the brain further consolidates memories and processes information, integrates them into the person’s world view, high level abstractions are formed, creative discovery is enhanced and problem solving occurs (hence the expression “sleep on it”).

Importantly, mood regulation and emotional processing also occur here via the amygdala.

The stages happen in succession and adequate time in each stage is required for the body to achieve benefits of sleep.

 
The Effects of Inadequate Sleep Quality

 What happens if you sleep with a snorer, or have a dog that barks when the wind blows or live on a busy street and as a result, your cycles are disrupted? In other words, what if you get through stages 1 and 2, but as you are entering Stage 3 something arouses you? Well, you go back to Stage 1 and miss out on the “magic” of Stages 3 and REM… uh oh!

Fragmented sleep, i.e., failing to complete the sleep cycles by awakening frequently, ravages the body impacting all areas of our health-no cell is left unaffected.

In addition, recent longitudinal studies have learned that the amount of time spent in each cycle changes with age. As we get older we spend more time in Stage 1 and less time in the critical later stages and these changes are associated with cognitive decline.
 
To complete our sleep cycles and to spend enough time in the later sleep stages, we need to build sleep pressure to fall asleep with relative ease (latency) and stay asleep for most of the night (quality) to achieve efficiency (time in bed vs. time spent sleeping) and reap the magic that sleep brings us.

All our sleep tips help achieve those goals! But the one tip that has the greatest impact on fragmented sleep is alcohol consumption. While a nightcap may help you conk out faster, alcohol will likely prevent you from entering the deeper/later stages of sleep, waking you in the middle of the night, increasing sleep debt.

Alcohol needs time to be metabolized at an approximate rate of 0.016% per hour. If you choose to imbibe before bed, try calculating the time it will take for your blood alcohol concentration (BAC) to drop to negligible amounts. (Please note: we are not encouraging alcohol consumption) Blood Alcohol Content (BAC) Calculator (Beer, Wine & Liquor)
 
TRACK YOUR PROGRESS

Use the calendar below to log your time in bed. If you have a sleep tracker, log actual hours slept. Note that the benefits of each resolution build upon the others, and the habits we develop are meant to stay with us well beyond the month the resolution is held. We will continue to log meals without sugar alongside our sleep progress.

Feel free to email your Motivated Mondays Coach Michele at [email protected] with your individual questions.​

YOUR MINI RESOLUTION: SLEEP BETTER

Log how many hours you've slept each day, and record which sleep tip you followed from the above link. Click or tap to view and download the log