Beating jet lag, our journey to Swakopmund

It took over 32 hours to get to our destination, Swakopmund in Namibia. First an 8 hour overnight flight from Brisbane to Singapore (after working a whole day); a 5½ hours layover; an 11 hour flight to Johannesburg; another 5 hours layover; then a 2 hour flight to Walvis Bay on a small plane; and finally a 1 hour car journey to Swakopmund. We met the tour group for dinner that night but I remembered trying desperately to keep my eyelids open and feeling like a zombie. That amount of time without sleep plus a 9 hour time difference played havoc with my body clock.


Circadian rhythm, the internal body clock that governs your daily eating and sleeping patterns, is controlled by melatonin, a hormone secreted by the pineal gland in the brain. During the day, exposure to light, specifically blue light, triggers light receptors on the retina that lead to suppression of melatonin secretion. When it's dark, melatonin is released and reduces alertness and makes you feel sleepy.

When we travel across time zones, it takes a few days for melatonin secretion to adjust to the new destination, thus giving us jet lag. Crossing more time zones, or travelling east, seem to increase the time to adaptation and therefore making jet lag worse. The number of days jet lag lasts, is roughly two thirds of the number of time zones crossed for eastward flights, or half of number of time zones crossed for westward flights. Eg From Brisbane to New York (travel east 9 time zones) will give you around 6 days of jet lag; whereas from Brisbane to London (travel west 10 time zones) will give you around 5 days.


Jet lag can be reduced by

  • Before travelling, ensure a healthy diet and plenty of sleep
  • You can plan a gradual shift to the new time zone by going to bed a little later if flying west, or a little earlier if flying east
  • Adjust your watch to the destination's time as soon as you board the flight and start eating and sleeping according to the new time zone
  • During the flight, drink plenty of water to remain hydrated, and avoid large meals, alcohol or caffeine. Sleep if you can but also remember to get up and stretch your legs to prevent DVTs (deep vein thrombosis)
  • As soon as you arrive, try to eat and sleep according to the new time. But try and avoid intensive sightseeing or important business meetings on the first couple of days when you may be less alert
  • If you're too tired and absolutely have to sleep during the day, keep naps short, up to 20 minutes
  • At night ensure a good sleeping environment free from noise or distraction, using eye shades or ear plugs if required. Do set an alarm to ensure you don't oversleep
  • During the day, exposure to sun light will suppress melatonin secretion and help adaptation

Medications
  • Melatonin tablets can help - a Cochrane review in 2009 showed that 0.5mg to 5mg melatonin taken close to the targeted bedtime (10pm-12midnight) are similarly effective, but people do fall asleep easier and sleep better when using 5mg. Doses above 5mg are no more effective, and slow release preparations (eg Circadin) are less efficacious.
  • Sleeping pills can be helpful although they may make you feel groggy the next morning, and using sleeping pills to sleep on the flight may increase the risk of DVTs. Some sleeping pills are restricted or banned in certain countries eg UAE.
  • Doxylamine (restavit or dozile) is an over the counter sedating antihistamine. It can help with sleep and can also be quite a useful medication for motion sickness or nausea and vomiting.


It probably was not the cleverest idea, but in order to maximise my vacation time, I planned on flying back home from South Africa to arrive at 8:30pm on Sunday before starting work again at 8am the next day. Using all the above tricks, my jet lag actually wasn't too bad. And by forcing myself straight into a regular schedule I have adjusted to home time a lot quicker. But, do as I preach, and not as I do. It's probably a good idea to leave a few days between coming home and starting work again.


For more info - http://wwwnc.cdc.gov/travel/yellowbook/2014/chapter-2-the-pre-travel-consultation/jet-lag

No comments :

Post a Comment