Is jet lag worse if you travel east rather than west? Does going with or against the rotation of Earth have an impact?
@JohnRei78302499
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Whenever your day gets shorter, your body has a hard time adjusting. I am a long-haul airline pilot. Flying east is always the problem. One of the hardest things to adapt to is the jet lag. It plagues the lives of those in my profession.
Dorothy Graham
Macclesfield, Cheshire, UK
As a dual national of the UK and the US, I have travelled back and forth between these places many times. The jet lag going westwards to the US isn鈥檛 too bad, but flying eastwards home to the UK is definitely always worse.
My theory is that the trip from the UK to the US, going west and hence travelling to earlier time zones, is like staying up late and sleeping in the next day. But coming back, you lose a night鈥檚 sleep and it takes at least three days to recover, no matter what you do. When there are no clocks or cues from light, I believe that the human body tends to adopt a 25-hour day. Maybe this is why it is easier to cope with extra-long days rather than extra-short nights.
However, some friends who worked abroad were convinced that jet lag was always worse coming home, whatever the direction of travel.
Richard Swifte
Darmstadt, Germany
It is widely acknowledged that jet lag is worse when travelling east, but this has nothing to do with the direction of Earth鈥檚 rotation.
Like many creatures, humans have a circadian rhythm that follows a 24-hour period and is kept in sync by the eyes鈥� response to natural light levels over the day. In fact, various studies indicate the average period is slightly longer than 24 hours, which would make it slightly easier to cope when flying west towards earlier time zones.
But probably the main reason is simply that it is easier to get to sleep later rather than earlier than one鈥檚 normal bedtime.
Hillary Shaw
Newport, Shropshire, UK
The human body clock is nearer 25 hours than 24 hours, as shown by experiments where people live for long periods in caves, with no clues as to day or night. Therefore, travelling westwards should be easier than going east and having to get up earlier than your brain 鈥渨ants鈥� to.
For short journeys east, say two time zones into Europe from the UK, this isn鈥檛 an issue: most of us adapt to the 1-hour biannual clock change within a day or so.
For longer journeys east, I force myself to stay awake the whole time 鈥� for example, for around 24 hours to Beijing, seven time zones ahead of the UK. Then, after arrival, I sleep for much longer than the usual 8 hours. Next morning, I am acclimatised.
Simon Dales
Oxford, UK
Yes, the direction you fly does make a difference, as shown by , which show a clear disadvantage for the teams travelling westwards.
Teams going west, say from New York to San Francisco, play later in their physiological day than the locals. For a 6pm kick-off, they feel as if it is 9pm, and well past their bedtime when the match finishes. But Californians competing in a match in New York play in their afternoon.
Nik Kelly
via Facebook
It also depends if you are a dawn or a dusk person: the former finds it better going east, the latter going west. The same applies when the clocks go forwards or back by an hour. As a night owl, I prefer the 鈥渇all back鈥� when the clocks go backwards in autumn.
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