英语拾零: Jet Lag

Jet lag means being tired and confused after a long plane journey, particularly when there is a big difference in time between the two countries.

Jet lag就是我们经常说的因为时差而导致的疲惫，倒时差的过程可是很痛苦的，长时间的飞行，再加上两个国家的不同时间，人们经常会被弄得颠三倒四。要想恢复，可得花上几天时间!

時差: Time difference


source: internet

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WHAT IS JET LAG?

Jet-lag is the curse of modern jet travel, resulting in loss of working efficiency and holiday enjoyment, often for days after arrival. Jet-lag can include a large range of effects from long-haul travel, incuding short-term symptoms such as dehydration and discomfort of legs and feet, and others which continue for days after the flight, such as fatigue, isorientation, lack of concentration and motivation, and broken sleep.

WHO SUFFERS FROM JET LAG?

A major US study shows as many as 94% of long distance travellers suffer from the effects of jet-lag, and 45% consider their symptoms severely bothersome.

A 1994 survey of flight attendants on international routes showed a similar picture, with 96% of respondents saying they suffered from jet-lag despite being accustomed to long-haul travel. Specifically 90% suffered from tiredness after arrival,73% from dehydration, 94% experienced lack of energy and motivation, and 93% reported broken sleep after arrival. Anecdotal evidence indicates jet-lag also makes travellers more susceptible to colds, flu and stomach upsets.

WHAT CAUSES JET LAG? It hardly seems possible that so many problems could result from merely travelling in an aircraft, but as the survey of flight attendants shows, it affects even the professionals. It is worse for passengers, partly because they are confined in their seats for long periods in flight. The greatest cause of jet-lag is rapid transit across world time zones. The time difference disrupts our body clock (circadian rhythm). This in turn affects body temperature, heartbeat, blood pressure and physiological patterns, leading to disorientation and mental and physical fatigue. Altitude and pressure changes at each landing and take-off also upset body systems, and although airliner cabins are pressurised, these changes are a significant cause of jet-lag. In addition, sitting still for long periods in flight causes discomfort and possible swelling of the legs and feet, and the dry atmosphere in airliner cabins can cause body dehydration. The effects of jet-lag may be made worse by excessive eating and consumption of alcohol in flight, by loss of sleep, and also by being tired or not in good condition before the flight, although these are not specifically causes of jet-lag.