Researchers at the University of Michigan have designed a new first-of-its kind app to fight jet lag.
The app, called Entrain, keeps track of how much light your body takes in at different times of day and uses mathematical formulas for tweaking that light exposure to help you adjust faster.
"Overcoming jet lag is fundamentally a math problem and we've calculated the optimal way of doing it," says Danny Forger, a professor of mathematics at the U-M College of Literature, Science, and the Arts. "We're certainly not the first people to offer advice about this, but our predictions show the best and quickest ways to adjust across time zones."
The idea behind the app comes from the premise that daylight helps regulate the body’s circadian cycle, which determines when you sleep and eat.
The app is named Entrain after entrainment, the scientific term for fully adjusting to a new time zone.
Jet lag can cause a host of symptoms, including insomnia, fatigue, trouble concentrating and stomach problems, Mayo Clinic reports. And symptoms tend to be worse the farther you travel.
And scientists have linked regular disturbances and disorders of the system to depression, certain cancers, heart disease and diabetes.
Entrain, is believed to be the first to take a numbers-based approach to synchronizing circadian rhythms with the outside hour. The LA Times reports.
The app uses your travel itinerary to determine what times of day you should seek the brightest light, and when you should put yourself in the dark, or at least in dim light.
You don't even have to be asleep, Science Daily reports.
If you must go outside, you can wear pink-tinted glasses to block blue wavelength light, the researchers say. And if the app prescribes "bright outdoor light" in the middle of the night, a therapeutic lightbox can do the job, they say.
Olivia Walch, a mathematics doctoral student who built the app, says “this is almost like a body hack to get yourself entrained faster."
The University of Michigan explains how it works:
–Start by entering your typical hours of light and darkness in your current time zone, then choose the time zone you're traveling to and when, as well as the brightest light you expect to spend the most time in during your trip (indoor or outdoor.) The app offers a specialized plan and predicts how long it will you take to adjust.
–Say you're traveling from Detroit to London, five hours ahead. Your flight leaves at 10 p.m. Eastern Time and arrives at 11:05 a.m. London time the next day. It's a work trip and you'll have to spend most of your time in indoor lighting. Under those circumstances, the app says it can adjust you in about three days. That's less than the rule-of-thumb one day per hour outside the starting time zone.
–The entrainment clock for any trip starts at the beginning of the first light cycle in the new time zone. So for the London trip, on the day after your arrival, you'd want to get light from 7:40 a.m until around 9 p.m., and not after. Rise earlier on the second day, at 6:20 a.m. Lights out at 7:40 p.m. You may feel like going for an evening walk, but being in the light at a time when the app prescribes darkness would lengthen the adjustment period, the researchers say.
–On the third day, get up before sunrise, around 5 a.m. Stay in light until 7:20 p.m. Your body will be synched the following morning. If you veer from the schedule, you can tell the app and it will recalculate going forward.
–To show how this new method is different, the researchers illustrate circadian rhythms as a clock with a point at the hour when your body temperature is lowest. This usually occurs about two hours before you wake up. If the point is usually at 5 a.m. and you travel overseas, it could abruptly swing over to, say, 3 p.m. in your destination. You're likely to experience jet lag until your system adjusts and your body is once again at its lowest temperature just a few hours before your alarm goes off.