What Causes Jet Lag and How to Avoid It 1. Facts ■ a long flight affects 【T1】________ 【T1】_________ ■ the natur

What Causes Jet Lag and How to Avoid It
   A long flight can affect one’s biological clock, sometimes for days. Air travelers can get very tired and develop unpleasant feelings when they fly great distances across time zones. The natural order of things can become unbalanced on long, overseas trips from east to west or from west to east. So today we are going to talk about jet lag and how to overcome it.
   The natural system tells our bodies when to sleep and helps to control many other processes. This internal body clock is affected by environmental signals, like sunlight and temperature.
   Sometimes we use the word "desynchronized" when talking about jet lag. This means to cause a process that takes place at times or in cycles independent of another process. In unscientific terms, you might say "out of sync" or "out of whack".
   Cells change their activity when a light is shown directly on them. They actually become desynchronized amongst the groups and within the groups. So when you feel out of whack with the environment after you experience jet lag, your nervous system actually reflects that same thing in becoming desynchronized within itself.
   In this state of desynchronization, communication between some neurons weakens. Using light to temporarily reset your biological clock before you travel could help to reduce symptoms when you arrive at your final stop.
   So here are some suggestions on how to fight jet lag.
   1. Try changing your meal and sleep times before you go
   Several days before you travel, start moving your bedtime and hours for meals closer to the times when you plan to eat and sleep on your trip.
   2. Start making small changes while in flight
   Change your watch when you get on the airplane. This is playing a trick on the mind. But it can help you to start thinking of the time at the other end of the flight. Try to sleep on the plane if it is nighttime in the place where you are going. Try to stay awake if it is daytime.
   3. Arrive early
   If you are traveling for work or for a personal reason, try to arrive a few days earlier, if possible. This will give your mind and body more time to correct to the new hours.
   4. Drink water
   Drink lots of water before, during, and after your flight. Avoid drinking alcohol or caffeine a few hours before you plan to sleep. Alcohol and caffeine can interfere with sleep. 5. Move around
   During your flight, get up and walk around or stretch so often. But after you land, avoid heavy exercise near bedtime. Exercise near bedtime can delay sleep, whether on an overseas trip or at home.
   If you travel, what are some tips you use to make it more enjoyable?...