Winston Churchill swore by them.
After polishing off a boozy lunch and a cigar,
the former British prime minister would climb into bed for an afternoon nap.
The last part of his regime may be worth imitating.
Sleeping during the day is usually the preserve of shift workers and cats.
But the science suggests that office workers can benefit, too.
A randomised controlled trial in 2023 found that nappers woke up
with improvements to mood, alertness and memory.
Napping habitually might also be wise.
A study from 2007 by the Harvard School of Public Health found that healthy adults
who took regular naps had a 37% lower risk of dying from heart disease compared with non-nappers.
One published in 2003 in Sleep Health suggested that habitual napping
could even add years to your life by slowing the rate at which your brain shrinks with age.
Timing is crucial, though.
Sleep scientists tend to agree that a short "power" nap, somewhere between ten and 30 minutes, is best.
For example, in 1994 NASA found that a 26-minute power nap enhanced pilots' physiological awareness and performance.
Sleep for too long and you enter the deeper phases of the 90-minute sleep cycle
and wake up feeling groggy.
You may also struggle to fall asleep at night.
Taking longer naps on a regular basis could even have deleterious effects.