How can athletes best overcome jet lag?

Long journeys and jet lag are a concern for many athletes, but what exactly is the impact of long flights on performance, and what strategies are available to counteract these effects?

Jet lag: How can athletes minimise its impact?

When I wrote this article, we were sitting in the time between the Olympic and Paralympic Games in Tokyo. Having previously written about the difficulties of the heat during the Games, I thought I’d consider another issue that was brought up frequently over the past few weeks. As with any Olympics — where people have travelled from far and wide — long journeys and jet lag are a concern for many athletes during the build-up to what could be the biggest few days of their life.

Today I’ll examine the impact of long flights and jet lag on performance. I will look at the underpinning science and strategies we might want to use to limit the effect on our next family holiday, business meeting or gold medal race.

Flying: Jet lag vs. travel fatigue

Firstly, we need to differentiate between two potential issues that may be at play when we consider long-haul travel. If we go on a long journey, let’s say a flight from London to Cape Town, this will mean a 12-hour flight crossing one time zone (during British summer time). The result of this would be travel fatigue. We would be tired from the event but would have different experiences from a 12-hour flight east, say from London to Tokyo, where we would pass through eight time zones. This second trip would be more likely to trigger the infamous jet lag that we heard so much about from British, American and many other athletes at the Tokyo Games.

We’ll start with a little explanation of the physiological difference between the two before diving deeper into the details of avoiding them.

What is actually happening to us up in the air?

Way back in 1997, the Godfather of sports chronobiology (the study of biological rhythms), Professor Tom Reilly, acknowledged the difference between travel fatigue and jet lag. He and colleagues summarised that travel fatigue, achieved via long trips (typically within three time zones of your origin), could be tackled with relative ease. They suggested this state was an acute accelerated tiredness and recommended simple amendments to training schedules and short periods of rest to allow individuals to return to normal following such trips.

They went on to acknowledge that once travelers exceeded three time zones,  experiences were much more noticeable, especially when travelling east. The exact reason for this east/west difference isn’t known, but it likely has something to do with the fact that advancing your body clock is trickier to deal with than delaying it. The general reason for our body struggling following time zone differences is that our internal body clocks become out of sync. Our brain gets confused when trying to determine the difference between where we are and where we think we are. This can also be exaggerated by novel issues such as a change in temperature, altitude, humidity, pollution etc., which has certainly been the case in Tokyo.

Beyond these factors, the key variable messing with our internal clocks is light. This is perhaps no surprise, and it is logical that if your body thinks it’s the middle of the day, but it’s pitch black outside, you may find it harder to go to sleep.

But beyond the annoyance experienced by anyone who’s ever had jet lag, from an athletic performance standpoint is it something we should be concerned with?

Jet lag and athletes: What’s the go?

It’s worth a quick glance at the science here to see what the impact of travel fatigue and jet lag might be on athletic performance. If, for example, our brains feel upside down, but we are still able to optimally perform, then maybe this would be less of an issue.

Starting with travel fatigue, it seems there is limited evidence that it might directly impact performance (assessed via counter-movement jump, yoyo test and technical/tactical performance). However, despite the potentially limited impact on physical markers, it was considered to negatively impact perceptual measures such as alertness, motivation, and mood, which would likely be a concern for athletes and coaches.

When we more specifically look at jet lag, it seems that crossing time zones increases resultant fatigue sufficiently such that performance markers including sprint and jump ability are negatively affected. It’s also suggested your chronotype (whether you’re a night owl who naturally likes a late bedtime, or a morning lark who prefers waking up early) may impact how affected you are, with larks appearing to adapt to eastbound travel more quickly.

Key strategies to reduce the impact of jet lag

Having established that, for long trips, especially when crossing multiple time zones, there are likely negative performance consequences, the big question is, what can we do about it? Below we will consider some pre-, during and post-travel strategies to help shake that funk as best we can.

Prior to travel
Firstly, it is important to try to embark on your journey in as fresh a state as possible. So, attempt to get a good night’s sleep leading up to your journey. It has also been recommended it may be useful to begin to adjust your sleep and waking time by one hour each day in the two or three days leading up to travel (especially when flying east). Greater adjustment than this is likely to be disadvantageous, with periods longer than two to three days likely to be too disruptive to an individual’s days before travel.

During travel
Once on the plane, it is recommended travellers attempt to make themselves as comfortable as possible. Many sports science departments are now taking this very seriously. During the Olympics, we saw special pillows on planes to aid rest, which you can even pick up yourself through the Team GB mattress sponsor. Incidentally, it was recently found that business class travel led to better sleep quality and quantity as well as reducing some jet lag effects – something to keep in mind if you’re looking to barter with the boss!
It has also been recommended athletes change their watches to the time at destination upon travel to aid the mindset shift. Sleep should then ideally take place during the ‘new’ night-time. Specifically, in the hour prior to attempting to sleep, it is advised to restrict computer, TV, and phone use. Loose fitting clothing, an emphasis on hydration and refraining from alcohol and caffeine have also been recommended. These interventions are based on evidence that exposure to light and noise can reduce sleep quality – aim to increase comfort and induce the physiological state required for sleep onset without pharmacological aids.

Upon arrival when having travelled west
Once you arrive at your accommodation, it has been suggested a short nap may be useful. This is aimed at suppressing the desire to go to sleep that can creep in when we extend our days by flying west. It is important, though, to keep this nap short (around 20 mins seems a good estimate) and seek some form of activity in the daytime once you’re up and about. This can lead to greater exposure to daylight, which can also aid the reduction of some jet lag symptoms.

You may also feel like going to bed 1 to 2 hours earlier than usual, subsequently waking earlier too. Don’t fret, though – this should pass after spending a few days in your new time zone.

Upon arrival when having travelled east
Things are a little trickier when we’ve flown east. This is because frustratingly, the time you feel most tired coincides with night-time in your origin time-zone, which is far from ideal if you’ve arrived into glorious sunshine at your destination. The key to cracking this and resynchronising your body clock is through manipulation of light after flying eastwards.

This comes through making the most of the positive effects of natural light at the right time. The problem with crossing many time-zones (e.g., six to nine hours) to the east is that a morning arrival worsens this issue. In such instances, the use of light shades on the plane and dark glasses en route to the immediate accommodation can minimise light exposure and allow the traveller to retire to bed until late morning if necessary after arriving. Subsequently, light exposure in the ‘new’ afternoon is beneficial.

It would also be beneficial to avoid training the first few mornings and train in the late afternoon instead.

Dreaming of gold: Take home points to maximise your performance

Generally, athletes, practitioners and us mere mortals are advised to firstly get the basics right when it comes to combatting jet lag.

Ensure you are protecting sleep prior to and during travel as best you’re able. Maintain adequate hydration by drinking to thirst and trying to avoid heavy meals and alcohol while travelling. 

Subsequently, small adjustments to your schedule may be considered in the days leading up to travel, as may manipulation of light before, during and after travel in order to aid resynchronisation of your body clock. 

Additionally, doing some exercise at the right time of day after arrival (morning when flying west, afternoon/evening when flying east) can reduce the impact travel fatigue and jet lag might have on performance while also aiding getting our body clocks back on track more quickly.

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