Jet Lag Syndrome

Top Ten Tips - Quick Reference

1. Our body is 'programmed' to be more sleepy between 3-5am and 3-5pm, and more alert between 8-10am and 8-10pm. When travelling, schedule meetings to fall into 'alert' windows, and naps and socialising into the 'sleepy' windows.
2. Crossing time zones probably means that you will be trying to sleep at times when your internal body clock says you should be awake. Improve alertness by supplementing reduced sleep with a short nap (45 minutes), or a longer nap (two hours). Remember that any sleep is better than no sleep.
3. Remember if travelling for only a few days, it may be most beneficial to keep your internal body clock on 'home time'.
4. Scientific research has shown that complicated diets, which involve patterns of eating carbohydrates and proteins, and feasting and fasting, don't work. Rather, you might want to keep your stomach on 'home time' while on a short trip.
5. While in flight drink plenty of water. Be cautious about alcohol use. Consumed within 3-4 hours of bedtime, alcohol can disrupt sleep quality and quantity.
6. Rather than drink coffee throughout the day, plan exactly when you need a lift and maximise the effectiveness of the caffeine you use.
7. Light has a powerful effect on your circadian clock. Used correctly, it can help your adjustment to a new time zone. Used incorrectly, it can make things worse. The general recommendation to expose yourself to light as soon as you arrive may not be helpful at all.
8. Always talk to your doctor before using non-prescription or prescription medications, and make sure you know the side effects of any medication.
9. Contrary to popular belief, exercise near bedtime will not wear you out. What it will do is wake you up, making it harder to get to sleep.
10. Sound machines playing relaxing music for background noise can aid sleep, but can be expensive. You can get the same effect from your personal stereo, by turning on a fan or tuning into static on a radio or stereo.

Rest and Alertness

The body's functions depend on co-ordination controlled by a timekeeper in the brain called the circadian clock. This synchronises internal systems such as the sleep and wake cycle, hormone levels, temperature, and digestion. This clock programmes us to be most sleepy twice a day: roughly between 3-5am and 3-5pm (regardless of how much we have slept at night).

How Does Jet Lag Affect Body and Mind?

When travelling to a different time zone, the circadian clock needs time to adjust. Not all of the body's internal systems adjust at the same rate - the sleep and wake cycle may adjust at one rate, while the temperature rhythm changes at a different pace. This creates jet lag.

Jet lag also results in sleep loss. Due to the time zone change, we may not be able to sleep at the appropriate local time. Then, during the day, when our body clock (still on home time) tells us to sleep, we may have difficulty staying awake.

How Alert Are You?

Pay attention to the signs of jet lag and fatigue, for example: reduced judgement and decision-making, forgetfulness, attention lapses, bad mood, lethargy, apathy and tiredness. If you recognise any of these fatigue signs, the following may help:

• Stop what you are doing, if possible
• Take a strategic nap (up to 45 minutes)
• Use caffeine (it takes up to 30 minutes to 'kick in')
• Engage in physical activity (move or stretch)
• Engage in social interaction (talk to someone)
• Short-term strategies for example listen to music or turn on a light (these strategies should last for only about 15 minutes)

The Internal Body Clock Prefers to Fly Westwards

Though we live on a 24-hour day, the internal body clock prefers to run longer. This explains why travelling in a westward direction is more body clock 'friendly' than flying in an eastward direction. When flying west, you are 'extending' your day and going in the natural direction of your internal clock.

Flying eastward will involve 'shrinking' your day in direct opposition to your internal clock's natural tendency. For example, London to New York involves extending your day by five hours, while the eastward New York to London flight results in 'shrinking' your day by five hours. In NASA studies of long-haul pilots, westward travel was associated with significantly better sleep quantity and quality than eastward trips.

What is sleep?

Humans have two types of sleep: Non-Rapid Eye Movement sleep (non-REM sleep) and Rapid Eye Movement sleep (REM sleep).

NREM sleep is the time when the brain and body slows down. The heart rate and mental activity decreases and breathing becomes more regular. NREM sleep is associated with our physical restoration during sleep and is divided into four stages, with stages 1 and 2, the lightest sleep and stages 3 and 4, the deepest sleep.

REM sleep is characterised by a very active brain; it is the time when we dream. It is thought that the fast eye movements that characterise REM sleep represent the eyes watching the activity in the dream. Mentally and physiologically, REM sleep is active and most associated with our mental restoration during sleep.

Every sleep period, we alternate through a pattern of about 60 minutes of NREM and 30 minutes of REM sleep. However, this pattern changes over the course of the night. Most of our deep NREM sleep occurs in the first third of the sleep period, while REM periods become longer and occur on a more regular basis in the second half of the sleep period.

The Sleep Debt

While on average adults need eight hours sleep, most people do not get this amount. Estimates suggest that each night, most adults usually get one to one and a half hours less sleep than they really need. The average sleep requirement for adults is about eight hours. If a person gets less than that, a 'sleep debt' is incurred.

If travellers average only six hours of sleep a night, they are building a nightly sleep debt of two hours, which accumulates with each night of sleep loss, and this can be a particular problem for the international traveller. This sleep debt can be recovered after sleeping for about eight hours each night for two consecutive nights.

Changing time zones, disrupting the internal body clock, and irregular exposure to light, food and exercise patterns can all result in disrupted and reduced sleep, and a cumulative sleep debt.

How Do Sleep Patterns Change with Age?

Significant changes in sleep are associated with getting older:

• Sleep becomes less deep; the deepest NREM sleep starts to disappear after about the age of 55.
• Sleep becomes more disrupted with more frequent night-time awakenings.
• We get less efficient sleep as our sleep becomes less consolidated at night; we maintain our need for the same amount of sleep and generally start taking more naps to correct the night-time disruptions.
• We are more likely to develop or be diagnosed with a sleep disorder; in any given year at least one-third of the adult US population reports a sleep disturbance.

Problem Sleeping

A 1998 survey conducted by the national Sleep Foundation indicated that 63 per cent of adults surveyed, complained of sleeping problems. The international traveller is particularly likely to report sleep problems due to the effects of jet lag. In a survey conducted by Hilton Hotels and the US National Sleep Foundation, nearly half of travellers (48 per cent) complained of sleeplessness while travelling.

The same survey indicated that some business travellers cope with the effects of sleeplessness by increasing their alcohol use at night (to try to help them sleep) and increasing their caffeine use during the day (to try to help them stay alert). But scientific research has shown that alcohol taken too close to bedtime can result in lighter, more disrupted sleep.

In addition to these remedies, travellers may be inclined to try other prescription or non-prescription medications to manage their sleep and alertness while on the road.

Good Sleep Habits

Sleep is an activity, or inactivity if you will, to which we dedicate a third of our lives, yet many of us still don't know how to do it properly. Sleep is a vital function, not a luxury. As with consuming food and water, if you did not sleep you would eventually die.

There is a tendency to think of sleep as an indulgence or as an inconvenience to be minimised. However, productivity and performance, particularly for the business traveller, can be significantly impaired with sleep loss and fatigue. It will not do a business any good if a person whose judgement, communication skills and attention are all reduced conducts negotiations. Getting better sleep while away actually begins at home.

We may not be able to eliminate jet lag and sleep disruption but there are effective strategies to improve your sleep at home, to minimise the effects of jet lag and to obtain optimal sleep given the circumstances. Remember, all sleep is good for you, and some sleep is better than none.

Strategies for Good Sleep

• Establish a regular pre-sleep routine: You can teach your body that it is time to relax and go to sleep by engaging in a regular routine of activities prior to bed. Reading, taking a warm bath, getting into pyjamas or listening to relaxing music can be routines that tell your body it's time for relaxation and sleep. What works for you will be different to that which works for someone else. Just remember, you want to engage in activities that will induce sleep (so avoid exciting books and the evening news).
• The sleep environment: Adjust the sleep environment and make it comfortable for you. Generally dark environments are best. Use an eyeshade or close the curtains. Cooler, rather than warmer, temperatures are best. Wear natural fabrics and dress in layers on the plane so you can add or subtract to stay comfortable. Random and loud noises are most disruptive. While on a plane, or in a hotel, try using ear plugs. In hotels, get reception to hold your calls. Radio or TV static, a fan or air conditioner can provide background, masking noise.
• The thirty minute "toss and turn rule": If you're awake in the night for more than 30 minutes, don't lie there watching the clock. You won't be able to force yourself to sleep. It is best to get up and do something that promotes relaxation and sleep. You might use relaxation techniques, listen to soothing music, read or watch TV. Just remember, make sure the content is not too stimulating or interesting - the goal is to promote relaxation. When you feel relaxed and sleepy, get back into bed and try again. A considerable amount of scientific literature has demonstrated the usefulness of relaxation techniques to help people get to sleep and stay asleep.
• Exercise is great but not too close to bedtime: Although exercise is important to help keep you fit and healthy, close to bedtime, rather than wearing you out, it can actually wake you up making it harder to get to sleep.
• Caffeine, tobacco and alcohol: Caffeine and tobacco are stimulants. Taken too close to bedtime they can disrupt sleep. Try to reduce your intake two to three hours before bedtime. Caffeine can be present in foods such as chocolate, frozen chocolate or coffee desserts, coffee ice-cream and frozen yoghurts as well as places you might not expect, such as cold medicines and pain relievers. Alcohol is the number one non-prescription sleep remedy in the US. A Hilton Hotel and US National Sleep Foundation survey of 1,000 international business travellers found that many use more alcohol while travelling to help them sleep. Too much alcohol, too close to sleep can actually result in lighter more disrupted sleep. Try to avoid alcohol within two to three hours of bedtime. Social drinking might be something that goes hand-in-hand with business travel, but it is not helpful to have that night-cap if you want to get a good night's sleep. As in many things, moderation may be the key.

Napping is Good

In a NASA study of airline pilots, a 40-minute nap increased alertness 100 per cent and performance 34 per cent. If you have a short period of time available, have a nap of up to 45 minutes. This length will reduce the chance of waking up from deep sleep and minimise the possible sleepiness and grogginess upon awakening.

If you have a longer period of time available, consider a longer nap of about two hours in length. This will let your body go through a full sleep cycle. Even if you have only five minutes to spare take a nap - some sleep is better than none. After the nap, give yourself about 15 minutes 'wake-up' time.

Checklist for Improving Your Sleeping on the Airplane or in the Hotel

Airplane:

• Wear an eye mask.
• Use a neck pillow.
• Use ear plugs.
• Wear several layers of clothing.
• Read a relaxing book.
• Drink plenty of water.
• Use a blanket.

Hotel:

• Limit caffeine, alcohol and tobacco within two to three hours of going to bed.
• Request a room away from noisy areas.
• Hang a 'do not disturb' sign on your door.
• Ask reception to hold your calls.
• Cooler is better than warmer, keep extra blankets handy if you need them.
• Wear an eye mask.
• Try relaxation techniques.
• Maintain a regular bedtime routine.
• Use the TV, fan or radio to create background noise.
• Have special comfort items: e.g., pillow, photos.
• Remember the 30-minute toss and turn rule.

Medications for Sleep and Alertness

With more than half of all adults experiencing problems with sleep, particularly when travelling, increasing numbers are turning to sleeping pills.

Over-the-counter sleep medications usually contain antihistamine as the active ingredient to create drowsiness and sleepiness. Generally these medications have little effect on the structure of sleep and generally few side effects.

Prescription medications are more complicated. Some can stay in your body for a long time (that is have a long 'half life'). Some prescription sleeping medications that have long half lives can lead to temporary problems with memory and attention because the sedating effects continue into daytime.
Some sleeping medications make you both sleepy and change the structure of sleep. None of these medications should be used with alcohol.

Non-prescription alertness products usually contain high doses of caffeine as the active ingredient. You should be careful if you take these with other stimulants, such as caffeine in other forms (e.g. coffee, tea) or nicotine. Caffeine is in other types of medications that can have the unexpected side effect of keeping you more alert. For example, some cough and cold medicines contain caffeine.

Melatonin

Melatonin has received a lot of international press coverage during the last few years, particularly regarding claims that it will aid sleep and relieve jet lag. There have also been claims that it will slow ageing and improve sexual function.

Melatonin is a hormone secreted by the brain at night. It is a chemical time cue that tells the brain it's time to sleep. It is sold in synthetic and 'natural' forms. The 'natural' form of melatonin is often obtained from animal brains. Although controversial, it is widely available in some countries, while it is banned and unavailable in others.

Melatonin purchased in health food stores has been found mixed with prescription sleep aids, powder and other substances. Current research will determine what is the best dose, how safe it is, long-terms effects, and when to take it. All of these factors suggest the cautious use of melatonin until more is known about how to use it safely.

Strategies for Using Medication While Travelling

1. Talk to your doctor before using non prescription or prescription medications.
2. "Ground test" any new medications at home before you travel. NASA astronauts aren't allowed to use any drug in flight that they haven't first tested on the ground "at home" and you shouldn't either.
3. Take the lowest effective dose for the shortest period of time.
4. Be careful about taking sleeping medications in flight. If you are groggy it may be difficult to follow cabin crew directions in case of emergency.
5. Know the side effects (on sleep or alertness) of all medications you are taking.
6. Don't borrow someone else's medication. You may not know how to use it safety and may not know how the drug interacts with other medications or substances that you might be using.
7. Don't mix non-prescription or prescription medications with alcohol and be careful about caffeine use.
8. Carry important medications in your hand luggage and bring an adequate supply for the duration of your trip.
9. Keep your medications in the original bottles, so customs won't have any questions about them.
10. Be careful purchasing medications away from home. Many drugs that are regulated in one country might not be regulated in another. Be sure that you know what you are purchasing and how to use it safely.

Caffeine

What's good when it keeps you awake and bad when it keeps you awake? The answer is caffeine - the world's favourite way to stay alert. As it is found in tea, coffee and caffeinated colas, caffeine is one of the most widely consumed substances in the world. It can stimulate you after you use it whether you want it to or not.

Some people, who consume a lot of caffeine, even at night, say that they are able to sleep well. Yet it is likely that even if they can get to sleep, the quality of their sleep will still be disrupted. With continuous use, it can take more caffeine to produce the desired level of alertness. Consuming greater amount caffeine increases the likeliness of disrupted sleep.

Caffeine and Business Travellers

A survey conducted by Hilton Hotels and the National Sleep Foundation found that many international business travellers increase their caffeine consumption when away on business trips.

Japanese travellers were most likely to report increased coffee use while travelling (43 per cent), followed by 39 per cent of Germans. British business people increased their coffee consumption by 31 per cent. Americans were last, with only 23 per cent indicating a likelihood of drinking more coffee when on a business trip. This information indicates that business travellers might try to manage sleepiness and fatigue experienced while travelling by increasing their coffee consumption.

Strategic Caffeine Use

So what can the business traveller do to avoid disrupting sleep with caffeine, but still enjoy its alerting qualities? The secret is in the knowledgeable use of caffeine.

Using caffeine strategically involves both knowledge and timing. You need to know how long it takes for caffeine to have an effect and how long it works for. Then you need to figure out when you will be most sleepy and plan the timing of your caffeine accordingly.

Caffeine usually takes about 15-30 minutes to 'kick in' and effects generally last for three to four hours. So, rather than drinking coffee throughout the day, plan exactly when you need a lift and maximise the effectiveness of the caffeine you use. For example, you have an important business meeting at 4pm when you know that you will be sleepy at that time. Since caffeine takes 15-30 minutes to take effect, you might plan to start taking the caffeinated beverages at around 3.30pm.

Points to Remember About Caffeine Consumption

Remember: stop drinking caffeinated beverages within a few hours of your planned sleep or it could keep you awake.

Most people expect to find caffeine in coffee, tea and caffeinated cola drinks. There is even a small amount in decaffeinated drinks, but it is in a lot of other places too, such as chocolate, frozen chocolate or coffee desserts, coffee ice-cream and frozen yoghurts, coffee flavoured sweets and medications such as cold medicines and pain relievers.

To make matters even more complicated, there may be different amounts of caffeine in different products throughout the world.

How Much Caffeine am I Consuming?

The following provides some general information about the amounts of caffeine in common foods and beverages in the US.

Coffee (per 8 oz serving)

• Instant coffee 102mg (max)
• Drip/percolated coffee 250mg (max)
• Espresso 70mg (max)

Tea (per 8oz serving)

• Brewed 83mg (max)
• Iced 50mg (max)
• Decaff 5mg (max)
• Soft drinks (per 12 oz serving)
• Coca-cola, regular or diet 47mg (max)
• Pepsi Cola 37mg (max))

Over-the-Counter Medications

• Stimulants 200mg (max)
• Pain relievers 65mg (max)
• Cold medicines 65mg (max)

Foods

• Frozen coffee desserts (1 cup) 85mg (max)
• Chocolate 31mg (max)
• Cocoa or hot chocolate (8oz) 5mg (max)
• Frozen yoghurt 45mg (max)