Power Nap — 90 Min

How to Use

Lie down fully in a dark room. This is a real nap — treat it like bedtime. Use headphones, close your eyes, and let yourself fall asleep. The session will carry you through a complete cycle and wake you at the lightest point. Give yourself the full 90 minutes without interruption.

How It Works

This session mirrors a complete 90-minute sleep cycle — the fundamental unit of human sleep architecture. You descend from alpha through theta into delta (deep sleep), where growth hormone peaks and physical restoration occurs. Then you rise into theta for a REM-like phase, where emotional processing and creative consolidation happen. By timing the wake to coincide with the natural return to light sleep, you emerge at the shallowest point of the cycle — the same reason you feel refreshed after exactly 90 minutes but groggy after 60.

Frequency Guide

Full cycle architecture: alpha (10 Hz) → theta (6 Hz) → deep theta (4.5 Hz) → delta (2.5→1.5 Hz deep sleep) → theta (5→6 Hz REM) → alpha (8→10 Hz) → alert beta (12 Hz). Mirrors the natural NREM→REM→wake progression.

Science & Research

A 90-minute nap encompasses one full ultradian sleep cycle. Research by Mednick et al. (2003) found that a 90-minute nap containing both SWS and REM improved perceptual learning as much as a full night's sleep. The REM phase is critical for emotional regulation and creative insight.

Tips

Reserve for days when you truly need recovery
Set a backup alarm for 95 minutes in case you want extra buffer
A dark, cool room makes a significant difference at this duration
Weekends and rest days are ideal — don't fight guilt, this is restorative

Precautions

Avoid after 2pm if you need to sleep that night
Not for daily use — can disrupt nighttime sleep architecture
Allow 5 minutes after waking before driving
May not be suitable if you have insomnia