Time lag, commonly known as jet lag, is a temporary problem in the sleep-wake cycle that affects human beings when travelling through various time zones in a short space of time.
Our bodies have an internal clock known as circadian cycle that establishes when we are awake and when to sleep.
This internal clock is synchronised with our time zone, our sleep habits and daily routines. When we move through time zones, misalignments arises in our time perception, meal times and sleep.
Although every person is different, jet lag is more noticeable when we go through more than 5 time zones.
The main agent responsible for jet lag is melatonin, a hormone we secrete through the pineal gland, in the centre of our brains and in charge of regulating the circadian cycle.
Every night, when our body detects the lack of light, more than 20,000 neurones send an impulse to the pineal gland so it may generate melatonin. All our bodies’ processes slow down and get ready for us to sleep.
So what happens when we fly? Well, in long haul flights, our bodies don’t detect the light changes, altering the whole process.
The duration of jet lag will very much depend on the person; for example, it won’t take the same for a pilot than for a passenger flying for the first time. Generally, however, it is said we need a day for each time zone we have travelled through.
The effects of jet lag are less when we travel west than east, but why? It’s mainly to do with flight times. Let’s take a look at the following example:
Flights from Madrid to the US usually depart at midday so they arrive at their destination around 18:00, whereas in Spain, it’ll be 23:00. If you go to bed around 23:00 (US time), your body will feel it has had an extremely long day, but it will still have been just the same day.
On the other hand, flights from the US to Spain depart around 22:00. So upon arrival in Spain it’ll still be the morning, or midday, meaning that after having been up and having flown for 9 hours, you’ll still have almost the whole day ahead of you.
But don’t worry! If you have followed all of our advice, you’ll have slept on the aeroplane and jet lag will be a lot easier to deal with.
In one of our last posts we talked about the Australian airlines Qantas’ project, for which an in-depth investigation on how jet lag is affecting us is being carried out so that we can gain a more thorough understanding of it.
The aim of the project is to develop techniques that allow to reduce the effect of jet lag in the ultra long flights the company wants to operate from Sidney.
If you’d like to know more about this, we suggest you take a look at our post Project Sunrise: Get ready for ultra long distance flights.
We hope you’ve found this article useful and it’s helped you find out a little more about the famous jet lag. If you’d like to continue learning facts about long haul trips, we recommend taking a look at our aviation blog where we tell you all about time zones or where do aeroplanes fly quicker towards.
