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Jet lag? There’s an app for that!

Young Woman in Airport Jeg Lag blogIf you have ever crossed time zones by plane and felt so exhausted afterward that it takes days to get back to normal, you have experienced jet lag. Now, with a new app called Entrain, you can monitor your body’s circadian rhythms using your smartphone—and adjust faster to new time zones and schedules.

Jet lag is the result of a disrupted circadian clock. Entrain simulates your circadian clock and makes mathematically optimal lighting recommendations to help you adjust as quickly as possible to new time zones and schedules. 

Entrain dashboard

Michigan app developers

The optimal lighting schedules were developed by Kirill Serkh, a doctoral student who worked on the project as an undergraduate at U-M, and Danny Forger, Ph.D., who holds faculty positions in mathematics at the U-M College of Literature, Science and the Arts and in the U-M Medical School’s Department of Computational Medicine and Bioinformatics.

Forger has long been involved in developing models of the human circadian clock. He and Serkh applied techniques from control theory to a simple model of the circadian clock to figure out how to transition the clock from one time zone to another as quickly as possible. The journal PloS Computational Biology published their research.

A few months before the publication, Forger asked Olivia Walch to develop an app to release the schedules to the public. Walch, a current University of Michigan applied and interdisciplinary math graduate student, designed and coded the app, which is now available for both iPhone and Android.

Entrain screenEntrain can collect important sleep data

“Since I wrote the app, we have been using it to collect data on the sleep habits of users around the world,” Walch says, but data is collected only with the user’s consent.

If users click the “Submit Data” button on the “Submit” page, their lighting history, travel schedule, jet lag ratings and responses to the demographic questions will be sent to servers at the University of Michigan anonymously.

“The data collection is just an add-on,” Walch says. “If users want to submit their data to us for research after a trip, they can opt-in to do so. We’ve had about 120,000 downloads of the app so far, and about 8% of users have opted-in to submit their data.”

Walch and Forger anticipate that, thanks to Entrain, new research findings about circadian rhythms will be available within the year.

To get over jet lag most efficiently

  • Experience one block of light and one block of darkness each day.
  • During the light phase, be in the brightest light possible.
  • During the dark phase, be in the dimmest light possible. Even a short burst of bright light at the wrong time can extend the time it takes to adjust.
  • Dark phases don’t have to be sleep phases.
  • If you must be outside during dark phases, block blue light with rose-tinted glasses or a visor.
  • If you are using the Entrain app, follow the customized, mathematically optimal schedule offered to you and adjust if necessary.
Take the next steps

U of M Health logoFor more than 160 years, the University of Michigan Health System has been a national leader in advanced patient care, innovative research to improve human health, and comprehensive education of physicians and medical scientists. The three U-M hospitals have been recognized numerous times for excellence in patient care, including a #1 ranking in Michigan and national rankings in many specialty areas by U.S. News & World Report.