Light provides your body’s most important cue for synchronizing circadian rhythms. Light exposure in the morning helps your body clock spring forward (just as clocks do at daylight saving time), and light at night prods your body clock to fall backward. Here’s how to use light to sync your body clock to the local time.
When traveling east:
●A few days before you leave, start exposing yourself to bright light in the morning.
●When you arrive, seek bright light in the morning hours.
When traveling west:
●Several days before leaving, seek bright light in the evening.
●When you arrive, expose yourself to light during the evening hours.
When traveling more than eight time zones east:
●On first and second days after arriving, avoid bright light during the first two to three hours after dawn. On the third day, seek bright light in the early morning.
When traveling more than eight time zones west:
●On Day 1 and Day 2, avoid bright light during the two to three hours prior to dusk. Starting on Day 3, expose yourself to bright light in the evening hours.
If these calculations seem too complicated, researchers at the Mayo Clinic have created a chart that can help: www.ccjm.org/
content/78/10/675.full.pdf. A smartphone app such as JetLag Genie (www.
jetlaggenieapp.com) can help you figure out your optimal light schedule.