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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Jet Lag vs Travel Fatigue: What's the Difference?

Jet Lag vs Travel Fatigue: What's the Difference?Jet lag is a circadian-rhythm problem caused by crossing time zones. Travel fatigue is a physical-stress problem caused by long sitting, dehydration, and the cognitive load of travel itself.How to tell which one you haveCrossed three or more time zones and feel wide awake at the wrong hour for several days? That is jet lag. Stayed within one or two time zones but feel wiped out? That is travel fatigue, and it clears with one or two normal nights of sleep.Why the difference mattersTravel fatigue resolves on its own with rest, water, and movement. Jet lag does not — it requires actively pushing your circadian rhythm in the right direction with timed light, sleep, and meals.When they stackOn long-haul flights you usually have both. Handle the fatigue first (hydrate, walk, eat a normal local meal, sleep at a reasonable local time), then run a circadian plan over the next several days for the jet lag.