Jet lag : all about it!

Hey
Again a copy paste post...
Found it informative, so sharing it.
The most important factor in setting our body clock is the cycle of light and darkness. However, our body clock does not cope well with rapid and large changes in the timing of environmental signals like light, which is what happens when we fly quickly across world time zones.

'Jet-lag' is the term used for the symptoms you may feel while your body clock adjusts to time in the new location. Symptoms of jet-lag include feeling tired during the day in the new time zone, and yet experiencing disturbed sleep at night, feeling less able to concentrate or to motivate yourself, decreased mental and physical performance, increased incidence of headaches and irritability, loss of appetite and gastro-intestinal problems such as constipation.

Jet lag vs Travel fatigue :

Any journey, particularly if more than 3 hours, can cause discomfort and tiredness whether you are travelling by car, bus, train or aeroplane. You may spend long periods in a cramped position and there may be other stresses such as delays, unplanned stops or detours. These symptoms do not last long and often improve after a rest, some light exercise, or a shower or bath. You will usually experience symptoms of travel fatigue after any long-haul flight, but you will only suffer from jet-lag if you cross several (probably more than 3) time zones. You only cross time zones if you travel eastward or westward, so you won't suffer from jet lag if you fly more or less directly north or south, for example from the UK to Africa or from North to South America.

Severity of jet lag :
The severity of jet-lag depends on the number of time-zones you cross and, to a lesser extent, on the direction of travel. For most people, the symptoms are worse if they travel eastwards than if they travel westwards. The symptoms may also depend on whether you are a morning-type "lark" or an evening-type "owl". There is little evidence that jet-lag symptoms are different between men and women, or between older and younger people.

How does one come out?
The symptoms of jet lag will naturally get better as the body adjusts to the new time zone. However, recovery may take 1-1.5 days per time zone crossed and there are a number of ways in which you can try to speed the process up. 

You can start the process of adjustment before you even leave home by changing the time at which you go to bed and get up. If your journey is eastward, for example from the UK to India, you could move your body clock forward by going to bed and getting up an hour earlier. Similarly, if you are travelling westward, for example from the UK to Canada, you could move your body clock backwards by going to bed and getting up an hour later. You should not attempt to re-set your body clock by more than 2 hours before you travel. 

If you have a choice of different flight schedules and arrival times, a late afternoon or early evening arrival might be better, since you can "use" the tiredness due to travel fatigue to help you get a full night's sleep in the new time-zone. 

The most important factor in setting our body clock is the cycle of light and darkness. Not surprisingly, exposure to (or avoidance of) light is an important factor in how quickly you adjust to a new time zone.

Exposure to daylight has the most effect, but the best time to be outdoors if you are trying to combat jet lag depends on your direction of travel and the number of time zones you have crossed.

So far so much!
Thanks!