12 New Methods for Deep Rest: The Sleep Revolution

5. R90 Sleep Cycle Technique

The R90 approach centers on the idea that human sleep organizes in roughly 90-minute cycles of lighter and deeper stages. Rather than aiming for arbitrary block lengths, R90 suggests aligning naps and sleep windows to these cycles so that wake times coincide with lighter stages, reducing grogginess. Practically, this means planning 90- or 180-minute nap windows and structuring nighttime sleep in multiples of 90 minutes where feasible. The technique is especially useful for shift workers, travelers, and people managing short recovery windows. Begin by experimenting with a single 90-minute nap in the afternoon and note whether you wake feeling clearer than after a short 20- to 30-minute doze. Use a simple timer and allow for a gentle wind-down before the nap. R90 isn’t a cure-all; it helps people make their sleep timing more compatible with natural cycles, which can improve sleep quality and daytime alertness when applied consistently. For full nocturnal sleep, R90 can inform sleep timing but still needs to be balanced with total nightly hours recommended for health and cognition.

6. Circadian Lighting and Smart Bulbs

Light is one of the strongest cues for your internal clock, and circadian lighting systems are designed to mimic natural daylight patterns indoors. These systems dim blue-enriched light in the evening and provide brighter, bluer light in the morning to support natural sleep-wake rhythms. For many people, swapping household bulbs for circadian-capable smart bulbs or using targeted light devices can reduce evening alertness and improve morning wakefulness. To start, prioritize bright light exposure soon after waking—natural sunlight when possible—and reduce overhead blue light in the two hours before bedtime. Affordable smart bulbs let you schedule color and intensity changes automatically, which takes the guesswork out of settings. If you work irregular hours, portable light devices or timed bulbs can help shift your rhythm more smoothly. While lighting isn’t a silver bullet, aligning indoor light with natural cycles supports both falling asleep and achieving deeper stages of rest, especially when combined with consistent sleep timing and evening wind-down routines.