28/02/2026
Why Short Naps Refresh and Long Naps Drag
Short naps feel refreshing because they usually stay within the light sleep stage (NREM stage 1–2). During these 20–30 minutes, your brain gets a quick reset without entering slow-wave sleep (deep sleep, NREM stage 3). Longer naps, around 60–90 minutes, allow your brain to enter deep slow-wave sleep and sometimes even REM sleep, which is important for memory consolidation and emotional processing. Waking up during these stages can interrupt the brain’s natural cycles, causing sleep inertia, making you feel groggy, heavy, and slow.