Jet Lag on Business Trips: An Hour-by-Hour Plan for Eastbound and Westbound Flights

How long does jet lag last, and what can you do about it?

That rate, from the CDC Yellow Book chapter on jet lag, turns a vague complaint into a schedule. Toronto to London crosses five time zones eastward; five hours divided by one hour a day is about five days. That division is our arithmetic on the CDC averages, not a promise. Age, sleep debt and the quality of the flight all move the result.

This plan is for the traveller who has to be useful on day one: the executive heading to a board meeting, the speaker opening a conference. It covers the days before you fly, the flight, the first day, and how to place the car, the hotel and the first meeting so the body clock is not fighting the calendar.

This is general travel advice, not medical advice. If you take regular medication, are pregnant, have a sleep disorder or are considering melatonin, speak to your doctor first.

Why flying east is harder than flying west

Westward is the easier direction. The CDC explains that the average human internal clock runs slightly longer than 24 hours, so people drift later naturally and find it easier to stay up late than to go to sleep early. Flying west asks you to delay your clock, which fits that drift. Flying east asks you to advance it, which does not.

So an eastbound traveller feels worse for longer. You land in the morning with a body that believes it is the middle of the night. A westbound traveller lands with a body that thinks it is early evening, then wakes far too early for a few mornings.

The US National Institute of General Medical Sciences says light and dark have the biggest influence on circadian rhythms. Its circadian rhythms fact sheet lists the short-term effects of crossing time zones: drowsiness, poor coordination, and trouble with learning and focus. The last two are the ones that cost money on a business trip.

Three typical business trips, side by side

The shift depends on direction and on the calendar. North America and Europe change clocks on different dates, so some shifts differ by an hour for a week or two.

Two points need explaining. On very large shifts such as New York to Dubai, some travellers find their clock moving the "wrong" way, by delaying rather than advancing; let your sleep and light timing show which way you are going. And Los Angeles to Tokyo is best treated as 8 hours westward, because the clock can delay by 8 hours more easily than it can advance by 16. Expect the first night in Tokyo to be rough all the same.

The short-trip exception: do not adjust at all

The CDC and the NHS agree on one case where you ignore the destination. If you are away for about two days or less, keep your home schedule for sleep and meals; the NHS suggests the same for trips of two to three days, to avoid adjusting twice.

That changes the meeting plan. A 15:00 meeting in London is a 10:00 meeting for a Toronto body clock, which is fine. An 08:00 start in Dubai is midnight to 01:00 for a New York clock that did not move. Put the meetings you must win in the destination's afternoon and evening, and avoid dawn starts that fall in your home night.

Before you leave: shift by an hour a day

Where you can, start the move at home. The CDC advises shifting your sleep by about one hour a day for two to three days before departure, later for westward travel and earlier for eastward travel. Three days of one-hour shifts moves you three hours of the way before you board.

For an eastbound trip to London, that means going to bed an hour earlier on each of the three nights before departure, and getting up an hour earlier, with bright light soon after waking. For a westbound trip to Tokyo, it means going to bed and getting up later. Few executives manage all three days. Even one day of shifting is better than none. Protect sleep, clear the last evening of late dinners and early calls, and pack an eye mask and earplugs.

On the plane: decide your sleep from the destination clock

The rule for the flight is simple. Sleep when it is night at your destination, and stay awake when it is day there. The NHS jet lag guidance says the same: sleep if it is night where you are going, use an eye mask or earplugs, and drink water.

For an overnight eastbound flight such as Toronto to London, that means dinner early, then sleep as soon as the cabin dims, because you land in the early morning in London. Set a phone alarm for the end of your sleep.

For a daytime westbound flight such as London to Toronto, you leave late morning and land in the early afternoon, Toronto time. Stay awake for the whole flight, since your body will think it is early evening on landing.

Cut alcohol and heavy caffeine in the air. Both promote dehydration and fragmented sleep, according to the CDC. Avoid sedatives with long half-lives; the CDC specifically warns against long-acting benzodiazepines and antihistamines.

Hour by hour: the first day after an eastbound flight

Take Toronto to London, landing at 07:30 London time, which is 02:30 for your body.

1. 07:30 to 09:00, arrival. Get through the airport and into the car. Wear sunglasses if the sun is strong, but get outside as soon as you can. Morning light at the destination starts to advance the clock.
2. 09:00 to 10:00, hotel. If the room is ready, shower and change. If it is not, use the lounge, but do not lie down.
3. 10:00 to 13:00, work. Keep this block for low-stakes tasks and calls. Use caffeine in moderation. The CDC suggests up to 200 mg every 4 hours during daylight for alertness, and stopping about 6 hours before bedtime.
4. 13:00 to 14:00, a short nap if needed. The CDC says keep it to 20 to 30 minutes, because longer naps interfere with night sleep.
5. 14:00 to 18:00, outdoors. Walk to the meeting, if it is close. Daylight is the strongest signal your body gets.
6. 18:00 to 21:00, the best meeting window. Your body reads 13:00 to 16:00, a normal working afternoon. Place dinners and negotiations here.
7. 22:00 to 23:00, bed. Avoid screens and bright light for the last hour. The NIGMS notes that light from electronic devices at night can confuse the body's clocks.

On day two, repeat the pattern and set an alarm. Resist the urge to sleep in.

Hour by hour: the first day after a westbound flight

Take London to Toronto, landing at 13:30 Toronto time, which is 18:30 for your body.

1. 13:30 to 16:00, arrival and transfer. Stay upright. Get outdoors for a few minutes before you go in.
2. 16:00 to 19:00, light work. Eat a normal dinner at a normal local time.
3. 19:00 to 22:30, stay awake. The CDC advises staying up until the destination bedtime westward. This is the hard part, because your body reads midnight to 03:30 by the end of it.
4. 22:30, bed. Expect to wake early, perhaps at what feels like 04:00.
5. If you wake early. Stay in the dark, avoid bright screens, and skip caffeine early in the morning, which the CDC specifically advises against on westward trips.
6. Next day. Take light in the late afternoon and early evening. Evening light delays the clock, which is what you want westward.

For a Pacific crossing such as Los Angeles to Tokyo, the same logic applies with a harsher first evening: you land in the afternoon with a body clock near midnight, so protect the first local night with a dark room and no alarm before 08:00.

Light, caffeine and melatonin: what the guidance says

Light does most of the work. The CDC says bright light after the lowest point of the body clock, about 2 to 4 hours before your usual waking time, advances it, while evening light delays it. So eastbound travellers want bright light early in the morning, home time, and should avoid it in the evening. Westbound travellers want light in the late afternoon and evening.

Caffeine is a tool for alertness, not for sleep. The CDC's limit is up to 200 mg every 4 hours during daylight, and it advises stopping six hours before the bedtime you want.

Melatonin is where the advice differs. The CDC says 0.5 to 1 mg is often enough, stresses that timing matters because the wrong timing can worsen the mismatch, and warns against doses above 5 mg. It also notes that melatonin is not regulated by the FDA, so the contents of a product can vary. The NHS, in contrast, says melatonin tablets are not recommended for jet lag on the NHS because there is not enough evidence that they work. Both are cautious positions. Ask your own doctor or pharmacist rather than taking a friend's suggestion.

Plan the car, the hotel and the first meeting together

Jet lag is a calendar problem as much as a medical one. Three decisions fix most of it.

The airport car. After an overnight flight you are poorly placed to drive. The NIGMS lists poor coordination among the effects of crossing time zones, and a rental car on an unfamiliar road at 08:00, when your body says 03:00, is the wrong place to find out. A pre-booked chauffeur who tracks the flight lets you sleep or work in the back seat. Onroutz.ca's executive car service covers Toronto and, through partners, Europe, the Middle East, Asia-Pacific and the USA.

The hotel. Book the night before, so the room is ready when you land, and ask for a quiet room away from the lift. A room that is ready at 08:00 is worth more than an upgrade.

The first meeting. Treat the destination afternoon and evening as your best hours after an eastbound flight, and the late morning as your best hours after a westbound flight. For a conference or a multi-day programme, our guide to corporate meetings, hotels and resorts covers how to sequence arrivals so the whole group is not at its worst on the opening morning.

If you have several meetings in a day, a personal driver removes the parking and the navigation, so the only thing you manage is your own energy. The full list is on our services page.

Reserve your car

Mistakes that make it worse

• Sleeping in on day one. It feels kind and costs a day.
• A long afternoon nap. Past 30 minutes, it steals the night.
• Sleeping tablets as a routine. The NHS notes they can be addictive.
• Heavy drinking on the plane. Dehydration and broken sleep arrive together.
• A dawn meeting after an eastbound flight. Move it, if you can.