Optimization
Caffeine and naps: using them well on day one
On arrival day, two tools help you last until the evening: a well-timed coffee and a short nap. Used badly, they sabotage the first night.
- 4 min read
- Fuseo team · September 2026
- Optimization
Caffeine works longer than you think
In one study, a high dose of caffeine taken 6 hours before bedtime still cut sleep by more than an hour, often without participants noticing. How long it acts varies greatly from one person to another.
Practical tip: keep coffee for the start of the day at your destination, and stop well before your planned bedtime. Fuseo shows the time of your last coffee for each day.
Naps, yes, but short ones
NASA studied long-haul pilots allowed to rest for 40 minutes in the cockpit. They slept 26 minutes on average, and both their performance and alertness were better afterwards than those of crews without rest.
A short nap of 20 to 30 minutes in the early afternoon helps you last until the evening. A long nap on arriving in the morning, on the other hand, delays falling asleep at night.
Coffee in the morning, not the afternoon; a nap of 30 minutes at most in the early afternoon, no long nap on arrival.
References
- Drake C et al. Caffeine effects on sleep taken 0, 3, or 6 hours before going to bed. J Clin Sleep Med. 2013;9:1195-1200.
- Rosekind MR et al. Crew factors in flight operations IX: Effects of planned cockpit rest on crew performance and alertness in long-haul operations. NASA Technical Memorandum 108839. 1994.
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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