The Science of Napping: Recovery Without the Hype
Evidence review updated: September 6, 2026.
Naps can improve alertness and may help performance when nighttime sleep has been short. They are a useful tool, not a replacement for adequate regular sleep.
Choosing a nap
A brief nap—often around 20 to 30 minutes—limits the chance of waking from deeper sleep and feeling groggy. A longer nap provides more sleep opportunity but may cause sleep inertia, so allow time to become fully alert before driving or training. Individual responses vary.
Earlier afternoon naps are less likely to delay bedtime. If you have insomnia, long or late naps may reduce sleep pressure and make nighttime sleep harder. Shift workers and athletes with unusual schedules may need a different plan.
Create a quiet, dim, comfortable setting and set an alarm. After waking, allow a few minutes for movement and light exposure. Caffeine immediately before a brief nap can increase later alertness for some adults, but it can also interfere with subsequent sleep.
Needing frequent naps despite adequate nighttime sleep, or falling asleep unintentionally, can signal insufficient sleep, medication effects, sleep apnea, or another condition. Discuss persistent excessive sleepiness with a clinician.