The Matt Walker Podcast

#03: Circadian Rhythms

August 26, 2021 Dr. Matt Walker
The Matt Walker Podcast
#03: Circadian Rhythms
Show Notes

#03 Circadian Rhythms

Continuing on from last week’s episode about sleep pressure, today, Matt Walker dives into the second half of the sleep-wake story, circadian rhythm. 

Matt explains that your circadian rhythm, or your 24-hour internal clock, begins drumming out its loud activating beat just before you wake in the morning and gets louder throughout the day, peaking in the early afternoon and hitting its lowest point in the middle of your sleep phase overnight. 

Matt describes how circadian rhythm and sleep pressure work independently of one another, yet coincide with a beautiful synchronicity to naturally and gently rouse you from sleep in the morning and rouse you into full wakefulness, then pull you into a wonderful, restorative sleep at night. 

You’ll also hear about the reliable mid-afternoon drop in alertness we see each day, what this means in terms of how humans were designed to sleep, and why it may explain the occasional need for a siesta.


The episode is sponsored by the wonderful folks over at Athletic Greens, who are providing a discount and free product if you use the link above. Athletic Greens is a comprehensive daily nutritional beverage containing 75 vitamins, minerals, and whole food-sourced ingredients, including a multivitamin, multimineral, probiotic.

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Finally, if you have thoughts on sleep topics that you want Matt to cover, or you have feedback you’d like to share so he can be better at podcasting, please reach out to Matt on Instagram @drmattwalker. He'd love to hear from you🤗!