Jet lag is a common symptom of long-haul travel, but its effects can be diminished
JET LAG and travel fatigue are integral parts of travelling. There are a number of simple strategies you can put in place to make sure that the transition to your destination is smooth and stress free.
It is important to plan your itinerary well in advance of departure. This includes checking whether you require visas and inoculations for your voyage.
While flights and transfers are scheduled, you should be prepared for delays. If you are physically active, try to avoid any heavy training the day before travelling. Keep exercise light or take a rest day.
Depending on the direction of travel, partial pre-advancement or delay of the body clock has been suggested by going to bed an hour earlier or later before departing.
Arrive at the airport with plenty of time - Dublin airport can be chaos, particularly in the summer, and being late will only add to the stress. If you are travelling in the morning, you may want to consider staying close by the night before. In order to start to adjust your body clock, as soon as possible set your watch to local time at your destination.
What to bring with you in your hand luggage:
• passport and visa if required (these usually need to be valid for at least six months)
• tickets
• essential items like currency
• inflatable neck pillow, eye mask and ear plugs
• music (ipod, walkman)/ laptop/gameboy
• reading material/games
• water, but don't forget that current security restrictions mean that liquids can only be transported in hand luggage in small quantities (100ml)
• some light high-carbohydrate snacks - don't rely on airline food for nutrition!
During the flight
Travel in loose, comfortable clothing. Keep active during the flight - the cabin provides limited opportunity for movement, so try to get up, walk about and stretch at regular intervals.
For those who are overweight, elderly or have cardiovascular disease, the use of compression stockings is recommended to prevent the risk of lower limb swelling or DVT.
Although you may feel drowsy and want to sleep during the flight, try and stay awake at times equivalent to daylight hours at destination. Appropriate recreation such as watching a film, reading, playing a game or walking around may help.
The cabin is a pressurised and dry environment, which can lead to dehydration and headaches, so make sure you drink plenty of water or fruit juice. Try to avoid alcohol, and minimise caffeine-based drinks as these increase the risk of dehydration.
Jet lag has also been associated with irregular bowel movements and constipation. It is therefore recommended to eat roughage such as apples, or other fruit and vegetables during the flight. From a hygiene perspective, in a confined space it is important to wash your hands regularly, especially before eating. You can purchase travel-sized alcohol sprays from the pharmacy, which are ideal.
During the flight, gradual pressure changes will affect the air-filled cavities of the body such as the middle ear and the nasal sinuses.
Upon ascent, the lowering pressure will lead to air escaping from these cavities to equalise the pressure both inside and outside the body. During this phase there is generally no discomfort experienced.
In contrast, during the descent the pressure in the cabin will slowly increase, promoting air flow back into the air cavities. This can lead to ear blockage, usually resolved by regular swallowing and moving the jaw. It is recommended for infants to use a bottle or pacifier and chewable sweet for older children.
What to do on arrival
If your journey involves travel across three time zones or less, jet lag is unlikely to be a major issue, but travel fatigue will still be a factor. Your body clock is slow to adjust to a change in schedule caused by travel across time zones. The aim is to safely speed up the process.
If you arrive at your destination in the early morning, a short recuperative nap until midday may be a good idea, followed by a cool refreshing shower. The remaining part of the day should be spent outside in the shade with exposure to natural daylight. For the remainder of the day, try to stay awake until it is time to go to bed.
Bright light exposure at appropriate times will assist in your body clock adjustment and minimise the effects of jet lag. Recommended activities on the first afternoon after travel include light exercise or just orientating yourself to your new environment.
Try and avoid naps for the next few days if possible. If you find yourself waking early, try to stay in bed until it is time to get up. Participate in local timing of activities as soon as possible such as mealtimes and sleeping. Take a rest day the day you arrive and keep physical activity at a low level for the next few days.
Only once you have acclimatise and your body clock has fully adjusted to the new time zone will physiological and cognitive function normalise.
As a general rule of thumb, for flights traversing more than three time zones, it takes approximately one day per time zone crossed for your body clock to fully adjust. In most cases involving travel across a number of time zones, this adjustment typically takes between five and 10 days, and generally longer the greater the number of times zones crossed.
• Dr Giles Warrington is a sports and exercise physiologist and lecturer in the school of Health and Human Performance at Dublin City University