Updated 19 May 2015

Jet lag

Jet lag results when one's “physiological clock” gets disrupted after hours of flying.

  • Jet lag is more than mere tiredness after a long journey
  • The symptoms experienced when your physiological clock is disrupted (“confused”) are referred to as “jet lag”.
  • Jet lag seems to be more severe when travelling from west to east than east to west.
  • Precautions can be taken before the flight, during the flight and upon arrival.

What is jet lag?

Jet lag should not be confused with the tiredness that one feels after a long journey in a car or after flying north or south for a considerable number of hours.

One’s body functions are controlled by a “physiological clock” which gets disrupted when one flies from east to west or vice versa to destinations in different time zones.

The symptoms experienced when this “physiological clock” is disrupted (“confused”) are referred to as “jet lag”.

What are the symptoms?

  • Feeling of tiredness during the day upon arrival at one’s destination.
  • Listless and unable to perform or train optimally.
  • Change in normal bowel activity eg. constipation.
  • Unable to fall asleep at night.

The duration of the jet lag would depend on the number of time zones crossed. The symptoms will last one day for every time zone as well as what measures were taken to eliminate these symptoms.

Jet lag seems to be more severe when travelling from west to east than east to west. Therefore South African sports teams playing in Australia or New Zealand will continue to be at a disadvantage when playing away from home.

It theoretically would take South Africans who are travelling to Oceanic countries between nine and eleven days to recover from jet lag if precautionary measures are not taken.

Who is at risk?

Trained sportspersons tend to cope better than administrators or untrained sportspersons.

Older individuals tend to have more severe symptoms.

Prevention and precaution

Precautions can be taken before the flight, during the flight and upon arrival.

Before the flight

  • Suitable planning of training schedules/dietary needs prior to flight.
  • Adjust sleeping patterns to the new time zone the week prior to the flight, such as the time of rising and going to bed.
  • Adjust training times to coincide with that of your final destination.
  • Give yourself sufficient time to overcome the symptoms of jet lag prior to the commencement of an important event. In the event of the Oceania travelling it is advised to arrive there at least seven days prior to the commencement of competition.  

During the flight

  • If one is going to arrive at the final destination during the day, you should make every attempt to sleep on the plane. Short-acting benzodiazipines such as Imovane/Dormicum/Dormonoct have all been proven to be effective in inducing sleep, yet allowing people to wake up without headaches and alert after four to six hours sleep.
  • Minimise alcohol intake and avoid coffee or tea.
  • High carbohydrate meal prior to retiring but not large quantity.
  • Drink plenty of fluids during flight before retiring.  

Should one arrive at the destination at night one should refrain from sleeping. Instead do static exercises or walk inside the plane as much as possible.

Upon Arrival

Adjust to the destination’s time as soon as possible.

  • Bright light can “advance” one’s body clock so exposure to sunlight (outdoors) instead of getting into bed upon arrival is advised. Best time would be between 11h00 and 17h00.
  • Do not sleep during the day.
  • Increase fluid intake.
  • Melatonin capsules taken in the evenings have proved to be useful in some instances.
  • If you need to train after arrival, arrange training sessions in late afternoon and try to keep them to the bare-minimum in the first couple of days.

 Written by Dr Ismail Jakoet, MBChB, MSc Sports Medicine. General Manager: Medical at SA Rugby (Pty)Ltd.


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