There's no stopping jet lag, but you can hack your circadian rhythm to fix it faster. This is best done by exposing the photoreceptors in your eyes to light at specific times, which will help your inner clock readjust. But knowing exactly how much light and dark you need can get confusing. Previously, researchers’ prescriptions could be as specific as “get 500 watts of light at 1 p.m., 720 watts at 1:15 ... ”—which sort of takes the fun out of vacation.
University of Michigan professor Daniel Forger is out to make the process work for the layperson. He figured out that the fastest way to recalibrate the circadian clock is to get the appropriate amounts of light at dawn and dusk. Then he and his team created an app called Entrain, which advises when to turn the light on in the morning and off in the evening based on your typical schedule and the one you’re trying to adjust to. If Forger’s math is right, you’ll wake up feeling fresh in no time.