Summaries of research studies and reports. Each one has a full citation and a link to the original source, even when the result doesn't help our case.
ResearchReading time 4 min
"A 26-minute nap boosts performance by 34% and alertness by 54%." It's one of the most quoted findings in sleep research. Here is where it comes from and what it means.
26 minutes of sleep
Shorter isn't always worse. Experiments at Flinders University show that the most effective daytime nap is shorter than you might expect, and night shifts have rules of their own.
In hospitals, control rooms and production, night-time fatigue is a safety issue. A planned nap is one of the best-studied countermeasures.
Does an afternoon nap really make you sharper? Two large analyses give a data-based answer, and show where the evidence ends.
Research on the health effects of napping has good news and warnings. Here are both, because an honest picture is more useful than a pretty one.
Lack of sleep isn't just the employee's problem. RAND Europe calculated what it costs five major economies every year.
After a bad night, an afternoon nap may help not only your head but your legs too.
| Study | What was studied | Key finding | Article |
|---|---|---|---|
| Rosekind et al. 1994, 1995NASA, Journal of Sleep Research | 40-minute planned cockpit rest on long-haul flights | The nap improved alertness and performance, and the benefit lasted until landing | The NASA nap: what the pilot study actually showed |
| Brooks & Lack 2006Sleep | 5-, 10-, 20- and 30-minute daytime naps after a short night | The 10-minute nap was the most effective | How long should a power nap be? |
| Tietzel & Lack 2002Journal of Sleep Research | Naps from 30 seconds to 10 minutes | Under 90 seconds gave no benefit, 10 minutes did | How long should a power nap be? |
| Hilditch et al. 2016Sleep | 10- and 30-minute naps on a simulated night shift | 30 minutes was followed by sleep inertia, 10 minutes by very little | How long should a power nap be? |
| Smith-Coggins et al. 2006Annals of Emergency Medicine | 40-minute nap opportunity at 3 am, 49 physicians and nurses | Fewer attention lapses and less fatigue at the end of the shift | Naps on the night shift: what hospital studies show |