Best quote from The Lost Rhythm of Segmented Sleep: History of First and Second Sleep
We’ve become so obsessed with getting that 'perfect' eight-hour block of sleep that we’ve forgotten it’s actually a very recent invention; for most of human history, people slept in two distinct segments with a purposeful gap of wakefulness in the middle.
This audio lesson was created by a BeFreed community member
Create a lesson on the history of human sleep patterns from ancient times to today. Explain segmented sleep (‘first sleep’ and ‘second sleep’), siesta cultures, monophasic and polyphasic sleep. Include how artificial lighting and industrialization changed sleep habits, the psychological and biological benefits of each pattern, and compare which sleep style may work best for modern humans.
Frequently Asked Questions
Segmented sleep, also known as biphasic sleep, was the historical norm before the Industrial Revolution. According to historian A. Roger Ekirch, people typically slept in two distinct periods known as first sleep and second sleep. Instead of one continuous eight-hour block, individuals would wake up in the middle of the night for a period of wakefulness to socialize, reflect, or perform light tasks before returning to bed for their second rest.
A. Roger Ekirch is a historian who spent years researching old diaries and medical texts to understand human sleep habits. He discovered that for most of human history, people did not sleep in one long stretch. His research highlights that the modern obsession with a single eight-hour block is a relatively recent invention, and that our ancestors naturally followed a rhythm of segmented sleep with a purposeful gap of wakefulness in between.
The Industrial Revolution marked a major shift in how humans perceive time and manage their biological clocks. Before this era, waking up at 2:00 a.m. was seen as a natural 'watch' rather than a medical problem. As society moved toward standardized work hours and artificial lighting, the traditional rhythm of first and second sleep was replaced by the modern expectation of a single, uninterrupted block of rest, leading many to view natural wakefulness as insomnia.
Discover more
Learn stable AM/PM routines for better sleep
Learn stable AM/PM routines for better sleep
Consistent sleep routines are foundational to physical health, cognitive function, and emotional wellbeing, yet many people struggle with disrupted sleep patterns. This learning plan helps anyone experiencing sleep difficulties or energy fluctuations establish science-backed daily routines that work with their body's natural rhythms.
I want to learn how to fall asleep quickly
I want to learn how to fall asleep quickly
Modern stress and digital distractions have disrupted our natural ability to rest, making sleep onset a common struggle. This guide is essential for professionals and restless sleepers who want to master the science of relaxation and reclaim their nights through proven psychological and environmental shifts.
Overcome insomnia
Overcome insomnia
Insomnia affects millions of people and can seriously impact mental health, productivity, and overall quality of life. This learning plan is designed for anyone struggling with difficulty falling asleep, staying asleep, or waking too early, offering evidence-based solutions that address both the psychological and practical dimensions of sleep problems. Whether you experience occasional sleep disruptions or chronic insomnia, these structured approaches can help you reclaim restful nights without relying on medication.
Biohack my sleep for oeak daily energy
Biohack my sleep for oeak daily energy
In an era of chronic burnout, mastering your rest is the ultimate competitive advantage. This plan is designed for high-performers and professionals who want to leverage biological science to eliminate fatigue and unlock peak daily energy.
Sleep better
Sleep better
Quality sleep is the foundation of cognitive health and physical recovery in our fast-paced world. This plan is ideal for professionals, students, or anyone struggling with insomnia who wants to transform their rest into a competitive advantage.
Spot hidden habits killing productivity
Spot hidden habits killing productivity
In an era of constant digital noise, traditional time management is no longer enough to stay effective. This plan is designed for professionals and students who feel busy but unproductive, offering the tools to reclaim focus and master cognitive energy.
Sleep early, recover, and align rhythm.
Sleep early, recover, and align rhythm.
This learning plan is essential for high-performers and anyone struggling with burnout or irregular sleep patterns. It provides a science-backed framework to transform rest into a competitive advantage by mastering biological timing and recovery habits.
Explore Sleep, Culture & History
Explore Sleep, Culture & History
This plan bridges the gap between biological science and human history to provide a holistic view of rest. It is ideal for curious minds and health-conscious individuals looking to reclaim their well-being by understanding the evolution of the sleeping mind.
From Columbia University alumni built in San Francisco
"Instead of endless scrolling, I just hit play on BeFreed. It saves me so much time."
"I never knew where to start with nonfiction—BeFreed’s book lists turned into podcasts gave me a clear path."
"Perfect balance between learning and entertainment. Finished ‘Thinking, Fast and Slow’ on my commute this week."
"Crazy how much I learned while walking the dog. BeFreed = small habits → big gains."
"Reading used to feel like a chore. Now it’s just part of my lifestyle."
"Feels effortless compared to reading. I’ve finished 6 books this month already."
"BeFreed turned my guilty doomscrolling into something that feels productive and inspiring."
"BeFreed turned my commute into learning time. 20-min podcasts are perfect for finishing books I never had time for."
"BeFreed replaced my podcast queue. Imagine Spotify for books — that’s it. 🙌"
"It is great for me to learn something from the book without reading it."
"The themed book list podcasts help me connect ideas across authors—like a guided audio journey."
"Makes me feel smarter every time before going to work"
From Columbia University alumni built in San Francisco
"Instead of endless scrolling, I just hit play on BeFreed. It saves me so much time."
"I never knew where to start with nonfiction—BeFreed’s book lists turned into podcasts gave me a clear path."
"Perfect balance between learning and entertainment. Finished ‘Thinking, Fast and Slow’ on my commute this week."
"Crazy how much I learned while walking the dog. BeFreed = small habits → big gains."
"Reading used to feel like a chore. Now it’s just part of my lifestyle."
"Feels effortless compared to reading. I’ve finished 6 books this month already."
"BeFreed turned my guilty doomscrolling into something that feels productive and inspiring."
"BeFreed turned my commute into learning time. 20-min podcasts are perfect for finishing books I never had time for."
"BeFreed replaced my podcast queue. Imagine Spotify for books — that’s it. 🙌"
"It is great for me to learn something from the book without reading it."
"The themed book list podcasts help me connect ideas across authors—like a guided audio journey."
"Makes me feel smarter every time before going to work"
"Instead of endless scrolling, I just hit play on BeFreed. It saves me so much time."
"I never knew where to start with nonfiction—BeFreed’s book lists turned into podcasts gave me a clear path."
"Perfect balance between learning and entertainment. Finished ‘Thinking, Fast and Slow’ on my commute this week."
"Crazy how much I learned while walking the dog. BeFreed = small habits → big gains."
"Reading used to feel like a chore. Now it’s just part of my lifestyle."
"Feels effortless compared to reading. I’ve finished 6 books this month already."
"BeFreed turned my guilty doomscrolling into something that feels productive and inspiring."
"BeFreed turned my commute into learning time. 20-min podcasts are perfect for finishing books I never had time for."
"BeFreed replaced my podcast queue. Imagine Spotify for books — that’s it. 🙌"
"It is great for me to learn something from the book without reading it."
"The themed book list podcasts help me connect ideas across authors—like a guided audio journey."
"Makes me feel smarter every time before going to work"
"Instead of endless scrolling, I just hit play on BeFreed. It saves me so much time."
"I never knew where to start with nonfiction—BeFreed’s book lists turned into podcasts gave me a clear path."
"Perfect balance between learning and entertainment. Finished ‘Thinking, Fast and Slow’ on my commute this week."
"Crazy how much I learned while walking the dog. BeFreed = small habits → big gains."
"Reading used to feel like a chore. Now it’s just part of my lifestyle."
"Feels effortless compared to reading. I’ve finished 6 books this month already."
"BeFreed turned my guilty doomscrolling into something that feels productive and inspiring."
"BeFreed turned my commute into learning time. 20-min podcasts are perfect for finishing books I never had time for."
"BeFreed replaced my podcast queue. Imagine Spotify for books — that’s it. 🙌"
"It is great for me to learn something from the book without reading it."
"The themed book list podcasts help me connect ideas across authors—like a guided audio journey."
"Makes me feel smarter every time before going to work"
