I’ve always liked the idea of napping; you can never get enough sleep I feel. Sara Mednick, sleep researcher and author of ‘Take a Nap! Change Your Life‘ agrees. In a lecture she gives at Google, Dr. Mednick outlines her research on why naps help increase productivity and can help supplement regular night sleep.

I’ve summarized her main points and include the corresponding segment in the video:

Sleep works in three cycles:

• Stage 1/REM
• Stage 2
• Slow Wave Sleep (SWS) ~ 7 minute mark

Nap studies show that a 60 min nap in the middle of the day includes only SWS and helps keep performance from declining throughout the day. 90 minute naps involve both SWS and REM and improves visual memory as much as a nights worth of sleep. Timing of the nap is crucial; we naturally get more REM sleep in the mornings and, for morning wakers, SWS in the evenings/night. ~ 15 minute mark

The functions of the various sleep stages:

• For stage 2 (which you’d get in a 20 min ‘power nap’) – increased alertness and improved motor memory.
• For SWS – restorative, clears mind, helps spatial and declarative memory.
• For Stage 1/REM – Helps creativity, perceptual skills, also responsible for vivid dreams. ~ 20 minute mark

A lot of people say that napping doesn’t work for them. But Dr. Mednick insists that a midday nap of 20-30 minutes helps even if you don’t think you’ve slept because you still get into a state of relaxation akin to sleeping; power napping does not involve passing out. ~ 36 minute mark

Sleep inertia – the feeling of being groggy after taking a nap. Solution: start with 10-15 min nap, and make sure to get out of bed. Napping more than 90 mins (1 full cycle) provides no extra benefit, and often results in sleep inertia. ~ 41 minute mark.

And that’s jus’ the tip.