Long flight ahead? Prepare weeks in advance to avoid jet lag, scientists say
Scientists say you should start planning days or even weeks ahead to shift your body clock (Unsplash: Kevin Grieve)
As a nation of travellers, Australians endure long-haul flights that take a tremendous toll on our bodies, but we can avoid jet lag according to scientists from Sydney University working with Qantas to come up with answers.
- Light is the most important factor in jet lag
- Planning for adjusting your body clock should start far in advance
- Airlines can assist through cabin lighting and other components of the flight experience
As flights get longer, there are questions about how well travellers can handle that many hours on a plane.
Singapore Airlines is launching the world’s longest non-stop flight, 18 hours and 40 minutes from Singapore to New York, and Qantas is aiming for a 20-hour flight between Sydney and London by 2020.
Recognising the downsides of ultra-long-haul flights, Qantas enlisted scientists to look at ways to make the journey easier on passengers.
Researchers have now reported on their findings so far at a sleep conference in Brisbane.
Science says you’re leaving it too late
The first part of the study, begun early in 2018, involved researchers from the University of Sydney’s Charles Perkins Centre reviewing all of the relevant research into non-pharmacological ways to counteract jet lag.
Public health researcher Dr Sun Bin said none of the strategies so far had been effective at lessening the suffering.
So, what’s the secret to avoiding wasted days, dropping off into your lunch and being bright-eyed and bushy-tailed at 3am?
“What we do know is that light is the most important factor in jet lag,” she told RN Breakfast.
“And I think the other important factor that most people don’t talk about is planning.
“A lot of people go on international flights without thinking about how they are going to adjust on the other end. They just put up with it.”
The research tells us we need to alter our body clocks for days and even weeks before even boarding the flight.
And then we need to keep doing that inflight, along with avoiding alcohol and drinking enough water.
“The way you feel, the way you function — mentally through to bowel movements — is all ultimately controlled by your body-clock,” said Steve Simpson, academic director of the Charles Perkins Centre.
But the biological clock can only be reset by about 90 minutes a day, so planning is essential.
“What you can do is make sure you’re pushing as quickly as you can to the destination time zone and getting the timing of things right,” he said.
“Basically, jet lag is a mismatch between your body clock and the time at your destination,” Dr Bin explained.
“So what you want to do is to try and shift your body clock towards what the time should be where you’re going.”
The aim is to shift your body clock to match the time at your destination (Unsplash: Jeshoots)
For example, if you are flying from Australia to London, you are travelling west, which means you need to delay your body clock.
“In the days before you fly, you really should be going to bed a bit later, maybe half an hour; an hour later in the three or four days before you even get on your flight,” Dr Bin advised.
Getting out into the sunshine at your destination is too little, too late, according to the research.
“We’re very good at trying to get light at the right times, so trying to go outside in the sun during the day,” Dr Bin said.
“But what we’re not very good about is avoiding light when it is supposed to be night-time — so things like looking at computers, looking at your phones, all those things count as light input to the system.”
How airlines can help
A number of airlines are designing planes to improve how passengers experience long flights.
Some include features like cabin pressurisation to make breathing easier and larger windows that are electronically synced to darken or lighten with the cabin lighting.
Qantas is also redesigning lounges, updating in-flight menus, and offering onboard meditation classes.
“The circadian science is really solid,” Dr Bin said.
“We know that light shifts your body clock and we can do it really well in the laboratory — we don’t do it really well in practise, with actual passengers.”
Qantas is asking researchers for input into the design of cabin lighting.
“Obviously if the flights are getting longer, we need to make use of the time on the plane to try and shift the body clock, and that saves you time on the other end trying to adapt,” Dr Bin told RN Breakfast.
An example of using light to mitigate the effects of long flights was the Socceroos trip in 2017 from Honduras to Australia.
The team wore light-therapy glasses designed by the sports scientist Dr Craig Duncan.
These glasses expose the eyes to blue-green light that can be used to regulate sleep patterns and help reset body clocks by suppressing the production of melatonin, the hormone we start to produce at night as we wind down for bed.
Players wore the glasses to stay awake for the first leg of the flight — a 9.5-hour journey between San Pedro Sula and Honolulu — and then switched to dark glasses to encourage sleep for the last leg of the journey.
The plane was also kept dark for the 10 hours to Sydney, so the players could sleep and shift their body clocks closer to Sydney time.
Airlines are looking at things like cabin lighting, lounge design and other factors to help passengers adjust their body clocks (Unsplash: Tim Gouw)
The second stage of the research involves the Health and Wellbeing in the Air study, where some passengers on the 17-hour Perth to London route will be asked to wear devices that record physical activity, sleep and posture changes, and to fill out a questionnaire about their state of mind and what they eat and drink during the flight.
The information will be collated to build a picture of how different people are affected.
But Dr Bin believes there is more to be discovered about the impact of long-haul flights.
“One of the factors that is missing from a lot of the research is this idea of jet lag as travel fatigue, as well as a disruption of your body clock, and that is something that has not been dealt with at all,” she said.
“Passengers on a plane are exposed to potentially 20 hours of acceleration, vibration, a change in air quality and air pressure and oxygen levels, and we really don’t know what impact that has on their fatigue and on their wellbeing.
“So that is something that we really want to look into.”