Jet lag happens when fast travel across time zones desynchronizes your internal circadian clock from the local day-night cycle, leading to fatigue, poor sleep, and reduced concentration.

How long does jet lag last?

As a rule of thumb your circadian rhythm shifts roughly one hour per day, so a six-hour time change typically takes several days to fully adjust. Eastward travel is usually harder than westward.

Can a planner actually reduce jet lag?

Yes. A structured plan that times sleep, light exposure, and activity in the days before and after a flight can meaningfully shorten adjustment compared with doing nothing.

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How to Beat Jet Lag from the US to Japan: A Complete Guide

How to Beat Jet Lag from the US to Japan: A Complete GuideTokyo is 13 hours ahead of New York and 16 hours ahead of Los Angeles. Eastward shifts are usually harder than westward ones, and the long flight adds sleep debt on top of the phase shift.Two to three days beforeShift bedtime earlier by about an hour per day. Get morning light immediately on waking. Avoid caffeine after midday.On the planeReset your watch to Tokyo time at boarding. Sleep when it is night in Tokyo. Prefer flights that land between 14:00 and 19:00 local. Hydrate; skip alcohol.First 48 hours in JapanBright daylight within an hour of landing. Push to a normal local bedtime (22:00–23:30). Caffeine in the morning only.Sample plan: LAX to HNDDay −2 bedtime 22:30 / wake 06:00. Day −1 bedtime 21:30 / wake 05:30. Arrive 17:00, dinner 19:00, bed 22:30. Most travelers feel close to normal by Day 3.