Preparation
Preparing your clock before you leave
You can start treating jet lag before you even board the plane, by gradually shifting your sleep in the days before.
- 4 min read
- Fuseo team · September 2026
- Preparation
The principle
For an eastbound trip, researchers tested a simple method: bringing bedtime and wake-up time forward by one hour a day for three days, with bright light on waking. The internal clock advanced markedly before departure, which reduces the distance left to cover at the destination.
Flying west, it is the opposite: go to bed a little later each evening and seek light in the evening.
Fitting it into your life
Three days of shifting are not always compatible with work or family. Even one or two days of preparation, or a partial shift, reduce the gap to catch up. In Fuseo, you choose 0 to 3 days of preparation.
When not to prepare
For a very short stay, it is sometimes better not to shift your clock at all, or only halfway, to avoid a second jet lag on return. Fuseo offers these strategies automatically depending on the length of stay.
A few days of gradual shifting, with light at the right time, reduce jet lag even before departure.
References
- Eastman CI et al. Advancing circadian rhythms before eastward flight: a strategy to prevent or reduce jet lag. Sleep. 2005;28:33-44.
- Burgess HJ et al. Preflight adjustment to eastward travel: 3 days of advancing sleep with and without morning bright light. J Biol Rhythms. 2003;18:318-328.
These articles are for information only and do not replace medical advice.
Fuseo calculates your sleep, light and caffeine times from your flights.
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