Air travel and jet lag

Jet lag

Taking off, spending fourteen hours in the plane, crossing seven time zones, landing in Shanghai and then jumping into a cab to meet an important client… You might be setting off on a business trip or leaving for holiday and wondering how to flip through time zones without experiencing severe jet lag. Quickly travelling across several time zones during a long-haul flight is what causes jet lag. Waking up at three in the morning thinking you are going to be late, craving for breakfast at 11 p.m.: after a long transmeridian flight, you might feel quite confused. Learn how to deal with jet lag and smoothly land into a new time zone!

What is jet lag?

Jet lag is a disorder occurring when the body’s biological clock does not correspond to local time.

Eastward and westward travel

You may feel exhausted after having travelled from Finland to South Africa but your tiredness can only be due to all the hours you spent in the plane, not to jet lag. There is no (or only very little) crossing of time zones when flying from the North towards the South or the opposite. On the other hand, traveling from Barcelona to Sydney or from Prague to Toronto usually will trigger jet lag. The more time zones you cross, the stronger the jet lag effects. Also, adjusting to time change appears to be more difficult when travelling eastward: the body seems to recover better from a lengthened day (flying West) than from a shortened (flying East) one.

Resetting the clock

Crossing time zones at high speed inevitably disrupts the body clock. As the circadian cycle (sleep-wake cycle which lasts about 24 hours) is altered, the body’s usual rhythm is completely desynchronized. To adapt to time zone change, the body needs a little time. Depending on the person, adjustment may be a more or less short process. Usually, getting over jet lag is a matter of a few days but some people feel its effects for over a week. 

Jet lag symptoms

Upon arrival you will have changed the time on your watch within seconds but your body won’t instantly follow the clock hands. Jet lag symptoms, harmless though quite annoying, include:

  • insomnia, disturbed sleep;
  • sleepiness, feeling sluggish during the day;
  • fatigue;
  • stomach problems;
  • headaches;
  • irritability.

Things simply don’t seem right: this feeling of general awkwardness is also caused by time zone change. The day appears to be split up in an unfamiliar way: you may feel like you are having dinner at the wrong time, you might find yourself wondering why your alarm clock still hasn’t rung… People who are used to following a very flexible schedule often are less affected by jet lag.

Preventing jet lag

Land in Tokyo at 10 a.m., hurry to your business appointment scheduled for 1 p.m.… Arrive in Mexico at 2 p.m. and immediately enjoy some holiday fun… Can one avoid jet lag effects and really work efficiently or even enjoy oneself after a long-haul flight? A few tips for outsmarting jet lag.

Before travelling abroad

  • Flying eastward? Go to bed earlier than usual on the day prior to departure.
  • Travelling westward? Move your bedtime later on the night before you leave.

During the flight

  • As soon as you board the plane, adapt to your new schedule by changing your watch.
  • Get as much sleep as you can.
  • Eat light, drink plenty of water and avoid alcohol and coffee.

Upon arrival

  • Avoid napping.
  • Immediately stick to your new schedule: meal times, bedtime & wake up times…

Imagine…

Your eleven-hour flight to Los Angeles has exhausted you but upon arrival, afternoon has only just begun. Napping for two hours would probably cause you to wake up in the middle of the night and be unable to fall back to sleep. Adjustment to your new time zone would be delayed. Take a walk on the beach, explore Chinatown, go out to dinner with friends… Enjoy any activity which will prevent you from sleeping before nightfall!

To find out more about time zone change:

What is the time difference between the country you are leaving and your destination? Check the world time clock to figure it out.

Date of publication Jan 28 2013

Other articles on this subject

Traveling to a country where malaria is a risk
Yellow fever and the International certificate of vaccination
Trips and Vaccines: What to Look For
Travelling when pregnant
Health tip: how to avoid food poisoning
Before the departure: medical precautions
Health and travel: forewarned is forearmed!