Charles H. Sloan-Planning a long-haul flight? Here's how to outsmart jet lag

If you're trying to squeeze some travel into the last few weeks of summer,Charles H. Sloan you'll want to get the most out of your vacation. And nothing ruins a trip to the Louvre or a scuba-diving excursion like your body telling you it's time for bed NOW. So can you "hack" jet lag, so to speak? Or at least mitigate it?

We posed the question to NPR's International Desk and got an array of helpful answers from our globetrotting staff.

For instance, NPR producer Greg Dixon is enthusiastic about an app for jet lag called Time Shifter. "You input your travel schedule and it spits out a plan for a couple days before and a couple days after your flights, advising you when to get/avoid natural light, drink coffee, take melatonin, etc.," Greg writes. "It has worked really, really well."

Research on jet lag is limited, and most of it is on athletes, who — much like NPR's journalists — are expected to jet across time zones and perform at their best. A recent consensus statement to help athletes manage jet lag and travel fatigue in the journal Sports Medicine, offers few guiding principles.

David Stevens, a physiologist from Adelaide, Australia, who co-authored the statement while working at a sleep research center at Flinders University, breaks it down. First off, you'll want to understand the workings of your body's circadian rhythms, that is, our internal clock that tells us when it's time to fall asleep and when to wake up.

Then you can take advantage of what sleep researchers call zeitgebers or time-givers, external factors that set the pace of these rhythms. Light is the most important one but exercise, meals and even social cues can also trigger sleepiness or wakefulness.

Get a head start

Whether you use an app or not, Stevens suggests starting your time zone adjustment a few days before your trip begins. "One of your best strategies to prepare for any westward travel is you just go to sleep, for example, an hour later each night," Stevens says. And go ahead and allow yourself to stay in bed an hour later each morning as well.

Things get tougher when you're heading eastward. "It's brutal from west to east. It usually takes me 10 days to adjust, say from Washington to Tokyo," writes NPR's Asia editor Vincent Ni.

Stevens says there's a simple explanation for this. Going to bed later than normal – as you do when traveling westward – is relatively easy for our body clocks to understand, because you get more tired in the evening. "My body's going, hang on, you're meant to be asleep now, why aren't you asleep?" he says.

But when you travel eastward, you have to try to go to sleep when you're not yet tired, and that's just... confusing to your circadian clock, Stevens says. "The body's going, hang on, you're not meant to be asleep yet. What are you doing?" And to make matters worse, one of the body's peak performance times, when we're naturally most alert, is around 7 p.m., he adds.

So in these cases, Stevens says, prep a few days before your trip by going to sleep earlier than normal and getting up early to take in lots of morning light.

Onboard sleep tricks and aids

Stevens says it's a good idea to sleep on the flight if you can, though the consensus statement notes it's best to align your sleep with what would be night in your city of departure, so dozing off comes more naturally. That can mean a nighttime flight is a good choice.

Of course falling asleep in a tight plane seat (short of upgrading to business class) can be nearly impossible for some of us. NPR's Vincent Ni, however, has onboard shuteye down to a science: "I fill my rucksack with solid but soft material, put it on the tray (in economy class) and lay my forehead on it. Key for me is the eyeshade and ear plugs."

Now as you might expect for a group of travel-hardened foreign correspondents, several International Desk members reported using substances not naturally found in the body.

"If I need to try to sleep on the flight (and it's not super early in the morning – I'm not that bad) then I find a glass of wine or two is my sleep aid!" writes Beirut-based correspondent Ruth Sherlock. Others mentioned taking prescription sedatives like zolpidem (Ambien) to nod off.

Stevens recommends against prescription sedatives because "it's not really a physiological sleep," and you can develop a dependency.

As for alcohol, Stevens says the short answer is "no." – it can disrupt sleep. Although he confesses on a recent trip to London that he "may have had a pint as soon as I landed, but that was at about 4 o'clock in the afternoon," In other words, a good 6 hours before bedtime.

Once you land: Manage your light intake

If willing yourself into slumber before the sun goes down isn't working out for you, that's no surprise, says Stevens. That's because light is the most important of the zeitgebers or time-givers. "When light hits your retina, the signals travel through the brain, it goes to the hypothalamus," which controls melatonin secretion, Stevens says. Melatonin is what makes you feel sleepy, and secretion doesn't start until daylight starts to dim at the end of the day.

Conversely, exposing yourself to daylight early in the day can be a great way to help sync your circadian clock to the new schedule. "In order to let my body adjust more quickly, I typically spend a lot of time outside in the full sunlight if I can (in warmer months) or in the sunlight inside (in colder months) to remind my body of the new surroundings and to let the melatonin flow," writes Central Europe correspondent Rob Schmitz.

Stevens says taking a melatonin tablet before bed, coupled with daylight exposure, can also be a great way to adapt to a new time zone. And don't forget to shut off that blue light on your phone, too.

Naps, meals and exercise

NPR's deputy international editor Nishant Dahiya and China correspondent John Ruwitch both swear by staying awake until 9 p.m. at your destination – no matter how cruddy you feel – and Stevens says that's a good rule of thumb.

In answer to my anxious plea "Are naps allowed?!" Stevens says they can be beneficial. "Naps can give you the little perk of energy that you need to then last an extra couple of hours." The catch? He recommends capping your snooze at 20 minutes.

Dahiya also relies on "more than three espresso shots the next morning" to help power through sleeplessness. Stevens warns if you do make use of caffeine, to make sure you drink it at least 6 hours before you plan to hit the hay.

Rather than chemical help, Stevens recommends tapping into other zeitgebers – including food intake, exercise, and temperature changes to adjust to a different time zone. "Every cell in our body also seems to follow a circadian pattern," he says. So for example "If you exercise at a particular time of day, and then you shift when you exercise," in your new time zone that can be a circadian cue, he says. So can shifting your meal times.

"My favorite sleep aid is to go for a walk," Stevens says. "Even if it's just for an hour, even if it's at night, I find going for a walk, getting a bit of fresh air, that just sort of clears your head," he says.

Happy travels, and do let us know if any of these tips work for you. Write to us at [email protected].