Naps: Good vs. Bad and Rules for Effective Napping
Source: Eric Topal's Ground Truths, "A Master Class on Sleep" with Professor Yo-El Ju
Good Nappers vs. Bad Nappers
- People generally know which they are — good nappers fall asleep easily and wake up refreshed; bad nappers struggle to fall asleep or wake up groggy.
Rules for Effective Napping
- Keep naps before 3 p.m. to avoid interfering with nighttime sleep
- Limit to 30 minutes or less to prevent sleep inertia (the groggy, "brain in molasses" feeling that worsens with longer sleep)
- Set an alarm to avoid drifting into deep sleep
Benefits (for good nappers)
- Boosts cognitive function
- Can improve athletic performance before competition
Unintentional/Accidental Naps Are Harmful
- Dozing off in front of the TV = "junk sleep" (like junk food)
- Drains sleep drive, leading to worse nighttime sleep
- The fragmented, drowsy sleep doesn't reach restorative slow-wave sleep
Bottom Line
Scheduled, brief, early naps are fine for good nappers. Unplanned evening dozing is actively counterproductive and signals a need for better nighttime sleep quality or quantity.