Man napping at desk Not the best napping technique
Air traffic controllers in the US have been advised to take 26-minute naps,
after a string of incidents involving workers falling asleep. So is 26 minutes
the ideal length of time for a nap?
Five cases of air traffic controllers falling asleep on the job have been
revealed since March.
In three of those cases, disclosed by the Federal Aviation Association, workers
have been fired.
Now the National Transportation Safety Board (NTSB) is calling for "controlled
naps" to be built into nightshifts.
Referring to a 1995 study from NASA which he co-authored, NTSB member and
fatigue expert Mark Rosekind said that a 26-minute nap would improve
performance by 34% and alertness by 54%.
The answer
There was other supporting evidence that said naps of between 20 minutes and 30
minutes were beneficial, he said.
His call for work naps is supported by the controllers' union, which wants naps
to be allowed in both overnight and day shifts.
Beyond the aviation industry, combating fatigue is an issue that affects many
people across all professions, working day and night, although it carries
obvious risks in jobs that involve motoring or machinery.
But other experts are doubtful that 26 minutes is the optimum napping time.
It's a bit too long and risks you falling into a deep sleep, says Jim Horne,
director of the Sleep Research Council in the UK, which advises the government
on guidelines for drivers.
Start Quote
Once you get beyond 20 minutes, you risk a deep sleep and you can be much more
groggy when you wake up
End Quote Jim Horne Sleep Research Council, UK
"What we recommend is that a nap is combined with a cup of coffee so you have
some caffeine, and that takes about 20 minutes to kick in.
"Have a cup of coffee and get your head down. Done together it has a more
powerful effect."
It probably works out that a nap of about 15 minutes is best, he says, because
once you get beyond 20 minutes, you risk a deep sleep and you can be much more
groggy when you wake up.
"A lot of people take caffeine after they wake up, but you have a window of
opportunity of 20 minutes, so it will help you wake up. It works, there's no
doubt about it."
People can't instantly fall asleep, so it's impossible to exactly time how long
you will be asleep, he says. But even 15 minutes of dozing is beneficial.
"At least by having caffeine, you know that in 20 minutes you will feel more
alert."
If you haven't had a wink of sleep the night before, then this tactic won't be
enough to refresh you, says Mr Horne, but for those that have had merely a poor
night's sleep, it will work.
Early or late?
Longer naps would work if they became part of your daily routine, he says,
because your body would get used to it and could wake up quite easily without
feeling too groggy.
Longer naps can work too
Jennifer Ackerman, author of Sex Sleep Eat Drink Dream: A Day in the Life of
Your Body
Health writer Linda Wasmer Andrews, based in Albuquerque, New Mexico, also
believes 26 minutes is too long. She says a nap of between 10 and 20 minutes is
enough.
The timing of the nap is also important, she says. Putting your head down too
early means your body may not be ready to sleep yet, but a nap that is too late
in the day might make it harder to fall asleep come bedtime.
Early afternoon is often the best time, between 1-3pm, she says, when people
experience a post-lunch dip in energy.
Whatever the best strategy is, it's unlikely that the US air traffic
controllers will be adopting any such tactics soon.
Transport Secretary Ray LaHood has dismissed the proposal for on-the-job naps
to be implemented in the aviation industry.
He said workers would not be paid to sleep, and instead ordered for more
managers be hired to supervise nightshift workers and ensure they don't fall
asleep on the job.