How to end those wrong time blues

JET lag is a fact of life in distance flying, be it in a corporate Lear jet or economy class on a budget charter flight.

Rapidly crossing several time zones has a profound effect on the body's natural rhythms, creating a problem for many business travellers whose schedules may not allow them time to recover after a flight.

Medical research has determined that more than 70 per cent of international passengers suffer from jet lag, 20 per cent of them severely.

Symptoms include loss of appetite, disturbed sleep, slowed reflexes and impaired judgment.

A sense of disorientation may persist for some days after the flight.

More importantly, when travelling on business, judgment and reasoning faculties may be affected for a long time.

West-bound travellers can take heart, the ill-effects of their extended flying day are lessened by the body's internal clock already running in a circadian cycle, which is actually longer than 24 hours.

Flying east makes the days, and particularly the nights, much shorter, depriving the body of the opportunity to sleep normally and, therefore, demanding more time to recover.

Exposure to daylight at the right time after arrival can help to ''jump-start'' the body on to local time.

Researchers at Brigham and Women's Hospital in the United States have found that after a trip from San Francisco to Sydney, a few hours in the sun will stop the body clock from working on US time.

Another session outdoors will shift it into the Australian rhythm.

With exposure to interior light only, the same result will take 10 days.

Tricks such as remaining on ''home'' time, eating and sleeping wherever possible at normal hours, and even arranging meetings to coincide with ''peak'' time at home are all useful tactics for surviving a short trip away of up to 48 hours.

Longer visits require a more complete re-synchronisation to local times and conditions. This process can start before the plane leaves the ground.

Re-setting your watch to the time of your destination, and adjusting your routine on board to suit will prepare the body for the shock of being in the right place at the wrong time.

Light meals before the journey, gentle exercise and rest all help prepare you to survive a long flight.

Airlines recognise that many executives on business will not have time to make their own pre-flight checks, so do all they can to ensure the least stress in the air.

British Airways went back to basics when it redesigned its Club World seats to provide maximum comfort.

Flexible lumbar supports and large adjustable footrests, coupled with the generous width of the seat, give the impression of a ''favourite armchair'', which encourages rest and relaxation.

Being able to stretch out fully makes sleep far more refreshing.

The benefits of working through a flight without resting may be negated by the increased time taken to get over the ensuing fatigue.

Many airlines now prohibit passengers from using portable computers on board because they interfere with navigation equipment, so the chance to spend all night typing up reports, even if the computer batteries lasted that long, has been removed.

On-board electronic typewriters, however, are a recent option for the workaholic travelling on Emirates Airlines.

Carriers have paid great attention to the effect of food and drink on the body during flight.

Following the general trend to healthier eating, all carriers offer menus with light, easily digestible meals, often served at times to best suit the individual.

Drinking water or fruit juices is strongly recommended to counteract the drying effects of the cabin air.

The effects of drinking too much alcohol during a pressurised flight are well documented.

Red, itchy eyes, blotchy skin and dehydration are common results, and getting drunk is much more likely.

The natural desire to combat the monotony of a long flight with a few drinks, however appealing the entertainment, may lengthen the time it takes the body to recover from jet lag.