Sleep Pressure

Sleep Pressure – this may be the reason you’re asking yourself “why won’t my child calm down for nap and bedtime?”

If you’ve ever felt like you nailed the routine, dark environment and snuggles… and your child still won’t fall asleep, this blog is for you!

What you’ll learn from this blog:

What is sleep pressure and why is it so important?
How overtired and undertired can impact your child’s sleep
Other factors to consider

What is sleep pressure?

Sleep pressure, or sleep drive, is a body’s natural inclination to fall asleep after a period of wakefulness. This is a homeostatic response controlled by the neurotransmitter, adenosine. Essentially, the longer your child is awake = the more adenosine accumulated = the more sleep pressure built.

For those adults who love to consume caffeine, this stimulant blocks the adenosine receptor which means your body continues to promote wakefulness. This is why Moms love coffee!

Your child’s capacity for adenosine is minimal when a newborn (which explains why they can’t handle much awake time) and increases as your child gets older and their sleep patterns evolve. The rate at which this capacity for more awake time increases is an individualized experience which is why wake windows should be used as a guide and not gold-standard.

Sleep Pressure as a Balloon

Another way to think of sleep pressure is a balloon. During awake time, the balloon inflates (building sleep pressure). When the balloon is sufficiently inflated, it’s time for the balloon to rest (and your baby to have a nap). If the balloon is not inflated enough, the signal for sleep just won’t be there and if we try to force the sleep, it just won’t happen (e.g., protest at naps, bedtime battles, etc.) During sleepy time, the balloon deflates (reducing sleep pressure) until it’s wake time again to rebuild and inflate the balloon.

If the balloon is too inflated, meaning sleep pressure is in abundance, the balloon may burst! This may mean a very grumpy frantic baby due to overtiredness.

Why is sleep pressure important to understand?

By understanding your child’s unique sleep needs, it helps you understand truly what they need when it comes to naps and nights which will help create optimal sleep patterns and realistic expectations for the whole family.

For example, if your toddler, who needs a recommended 11-14 hours of sleep in a 24-hour period, has a chunky 2+ hour nap at daycare, they may not be ready for bed at 7pm (and they will let you know that by protesting bedtime). For a younger baby, if their total daytime sleep has been a lot (let’s say 3-4 hours), they may have relieved too much sleep pressure during their day and won’t have enough in the tank to help them through the night.

Simply put, if your child’s sleep pressure has been relieved too much during the day, bedtime and nights will be a challenge. Along the same theme, if your child’s sleep pressure hasn’t been built up enough throughout the day/evening, bedtime and the night will be a challenge.

Sleep pressure challenges can happen for any age and stage. Each challenge may present with a different solution depending on your unique scenario. Some solutions may include adding more awake time, taking away sleep time, shortening a nap, dropping a nap, and adjusting a bedtime.

So let’s determine what is overtired and undertired to help set your family up for success.

How can being overtired and undertired impact your child’s sleep?

Being “overtired” is a buzz word in the world of baby sleep and something many parents are nervous about (and I get it, no one likes a fussy frantic baby!) BUT, what this worry brings, is the safety net of too little awake time/not enough sleep pressure being built and an undertired baby which will also make for difficult naps and bedtimes. Seems like you just can’t win, right?

Regardless if your baby is overtired or undertired, they are going to signal this to you and as most babies and children do, they will protest. Seems like you just can’t win, right? But this is where you can become a “sleep detective” and find your baby’s sweet spot and adequate sleep pressure they need to thrive with their nap and bedtime routines.

Wake windows, while not evidence-based, can be helpful to guide your baby’s sleep patterns and give you a bit of guidance on how to support their daytime sleep needs. You can check out my wake window freebie here for a breakdown of wake windows for each age group.

Overtiredness can be the result of many things (nap transitions, too much awake time, skipped napped, later bedtime, poor quality sleep due to undiagnosed sleep health problems, etc.).

Common signs of an overtired baby and child may include:

Having a hard time falling asleep
Waking up from a shorter nap still visibly tired and/or grumpy
Short naps and waking grumpy
Increased whining and fussiness
Irritability
Silly and clumsy
Temporary increase in energy/giggles, what is referred to as the “second wind” or the “zoomies”

If your child is undertired, it may be the result of too much daytime sleep, too little awake time before bedtime/nap, too long of a final nap in the day, or not enough activity and stimulation during their awake time.

Common signs of an undertired baby and child may include:

Taking a long time to fall asleep (30+ minutes) and are restless during this time
Protest before naps/bedtime (they are communicating to you they truly aren’t ready for sleep)
Waking up from a shorter nap but happy/content
Older children may stall bedtime (e.g., asking for 101 things – they also may do this for other reasons too)

Other factors to consider about your child’s sleep

Analyzing your child’s sleep needs (through timing and their unique signals) can help you determine their optimal sleep pressure preferences and may be one step to eliminating bedtime and nap challenges. However, there are many factors to consider when analyzing your child’s sleep struggles and these are to always be taken into consideration for any sleep challenge.

Some (and this is not an exhaustive list) questions to consider:

Is this a developmental transition phase for them?
Are teeth breaking through?
Are they getting sick?
Are there big life changes happening for them (e.g., daycare starting, family dynamic change, room switch, sibling arrival, etc.)
Is there an underlying medical condition (sleep related or developmental) that is impacting their sleep?
Is their sleep environment optimal (e.g., temperature, darkness, familiar) or is it somewhere new?
Are they physically uncomfortable (e.g., gas pains, growing pains, allergies, skin sensitivities)?
Are your child’s sensory needs being met before bedtime routine and during the bedtime routine?
Is separation really hard for them? How can we support them with this?
Are they developing worries and fears?

A sleep journey

Baby and child sleep can be impacted by many variables and it’s important to recognize that there is no one-size-fits-all approach. Your child’s bedtime and nap behaviour is communication. If they had the capacity to tell you exactly what they were feeling and needed in those moments, they would but they can’t (for many reasons) and so it’s your job to be a detective and determine what they’re communicating to you. Being a detective can be challenging for some families when they are overwhelmed and overtired themselves. Because of this, working with a sleep consultant can be beneficial to many families to truly analyze a family’s sleep story from an objective lens and determine the best action plan for them. I use all my experience – academic, professional and personal- to support your family’s journey to more sleep. Your goals. My expert and compassionate support.

Wishing you a smooth sleep journey,

Chelsea

Chelsea is Mom of 2 and a Certified Baby, Toddler and Child Sleep Consultant with advanced certification in Infant and Early Mental Health and Pediatric Sleep Health. She supports families within Hamilton and beyond with hands-on, no cry-it-out, responsive methods. She has a Master’s of Professional Education (specialization in Applied Behaviour Analysis) and over 10 years of professional experience supporting families in the community. Chelsea works collaboratively with families to empower them with the confidence and tools they need to reach their unique sleep goals. Hear from rested families here and book a free call with Chelsea here to discuss how she can support your family’s journey to more sleep.