The Science of Sleep
How sleep actually works, and what to change tonight to get more of it.
For anyone who sleeps badly, wakes at 3am, or just wants more energy in the day. You'll learn the machine behind the advice: the two forces that put you to sleep, what your body clock listens to, and why trying harder to sleep never works. You finish with a two-week plan built from your own nights, and a clear list of the signs that mean seeing a doctor instead.
By the end you can
- Explain why you're wide awake at 9pm and foggy at 7am, using sleep pressure and your body clock
- Set your day's light, caffeine, meals and exercise so your sleep window lands where you need it
- Get back to sleep at 3am without making the night worse
- Run a two-week sleep plan on yourself and know when to take it to a doctor
How sleep works
- The two forces that put you to sleep
Sleep pressure builds all day; your body clock decides when it's allowed to win. Learn how the two work together, and why you get a second wind at 9pm.
- Sleep stages and the 90-minute cycle
A night of sleep is not one flat state. Learn the four stages, how they repeat in cycles, and why an early alarm costs you more dream sleep than you'd guess.
- What sleep does for you
Sleep is a work shift, not downtime. See what it does for memory, mood and your body, what one short night costs the next day, and why you can't train yourself to need five hours.
Your body clock
- Light, the master signal
Your body clock is set by light. Learn why morning daylight pulls your sleep earlier, why bright evenings push it later, and how to build a simple light plan for your day.
- Larks, owls and social jet lag
Some body clocks run early and some run late, and much of that is inherited. Learn your type, measure how far your days off drift from your workdays, and shrink the gap.
- Caffeine, alcohol and nicotine
Three everyday substances change your sleep more than you feel. Learn how caffeine hides sleep pressure, how long it stays in you, why alcohol's sleep is poor sleep, and what nicotine really does.
Building a good night
- The bedroom: dark, cool, quiet
Your body has to cool down to fall asleep, and your room decides whether it can. Learn why a cool room helps, why a warm shower cools you, and how to handle light and noise you can't remove.
- Wind-down and a fixed wake time
You can't decide to fall asleep, but you can decide when to get up. Learn why the wake time is the anchor, how to build a wind-down that works, and how to nap without wrecking the night.
- Food, exercise and screens
The three evening habits people argue about most. Learn what a late dinner really does, when exercise helps and when it doesn't, and why screens cost you more time than light.
When sleep goes wrong
- Insomnia: why trying harder backfires
With sleep, effort is the one thing that never helps. Learn how a bed turns into a place your body expects to be awake, the rule that breaks the loop, and what the evidence says to try first.
- Awake at 3am: a toolkit
Waking in the night is normal. What you do in the next ten minutes decides whether it costs you the rest of the night. Get a plan for the clock, the breathing and the thoughts.
- Your two-week sleep plan
Turn eleven lessons into one plan you'll actually run. Keep a simple diary, change one thing at a time, and know the signs that mean it's time to see a doctor instead.
Keep it, don't just read it
Pathwise brings each idea back just before you'd forget it, with a quick question. Free on Android and on the web, in English and Persian.