By Lucy Hooker of BBC
Last week, Damion Bailey posted on Instagram that he had just achieved his "personal best" - a 13-and-a-half hour flight between Shanghai and Dallas without any in-flight entertainment, films, books or music.
"It's quite tough, honestly," the 34-year-old from Miami, Florida tells BBC News. But he keeps doing it.
Bailey is part of a new travel trend, known as "raw-dogging", where passengers spend long hours mid-air just staring straight ahead.
The longer you do it, the tougher you have apparently proven yourself to be.
"Just raw-dogged it, 15 hour flight to Melbourne," boasts Australian music producer Torren Foot on TikTok, blinking hard as if to stay awake.
"No music, no movies, just flight map."
Some also avoid eating or drinking. A few say they won't get up at all, even to use the toilet.
But health experts warn that more extreme versions of the trend can pose serious risks.
Manchester City footballer Erling Haaland recently joined the trend, posting that he had got through a seven-hour flight with "no phone, no sleep, no water, no food" and had found it "easy".
Responses on social media questioned if he had really gone this long on a flight with no stimulation or sustenance. Others wondered if he was a robot. And some simply asked "why"?
Posts about "raw-dogging" have grown steadily over the last year.
Increasing numbers of young men - and it is mostly athletic-looking young men - are posting videos of themselves on board, staring at the in-flight map or the safety instructions card, vowing to use the "power of the mind" to get them through.
As for the term "raw-dogging", it might have carnal origins, but increasingly it is used for anything being done without protection or support.
For these men, the appeal seems to be the opportunity to prove their resilience and self-control.
Mental recharge or 'idiots'?
Some medical experts point out that the more extreme version of the trend - going without food, water and bathroom breaks - poses significant health risks.
"They're idiots," says Dr Gill Jenkins, a GP who also works as a medical escort in air ambulance work. "A digital detox might do you some good, but all the rest of it is against medical advice," she says.
"The whole thing about the risk of long-haul flying is that you're at risk of dehydration.
"If you're not moving you're at risk of deep vein thrombosis, which is compounded by dehydration. Not going to the toilet, that's a bit stupid. If you need the loo, you need the loo."
But on the trend as a whole, business psychologist Danielle Haig says she can see why people would want to spend time in quiet reflection, allowing their mind to wander, in our increasingly fast-paced, technology-driven world.
"It offers an opportunity to recharge mentally, gain new perspectives," she says.
She thinks the trend signifies "a collective yearning for balance as people seek to reclaim their mental space and foster a deeper connection with their inner selves".
And she reckons that raw-dogging allows young men, in particular, the chance to showcase their ability to handle solitude and discomfort with stoicism.
"The first time I did it was on a shorter flight, out of necessity," says Bailey.
"I forgot my headphones, and there wasn't anything on the entertainment that I wanted to watch."
But he has carried on doing it. "I like the challenge, for sure. I fly so often. Why not challenge myself?" he says.
Allowing yourself to be bored for a few hours is actually quite good for us, argues Sandi Mann, academic and author of The Science of Boredom. "It can really improve our relaxation and creativity."
People have to find ways to wean themselves off the constant "highs" they get from modern technology, she says.
"We need to reduce our need for novelty and stimulation and whizzy-whizzy bang-bang dopamine, and just take time out to breathe and stare at the clouds - literally, if you're on a flight," she says.
But she acknowledges all the current advice stresses the importance of staying mobile, particularly on longer flights, and also suggests avoiding food and water would pose added health risks.
"I think people need to understand this is not ideal for a seven-hour flight," says Mann. "You've got to get the balance right."
'Self-inflicted torture'
Clearly, it is not for everyone.
"Sounds like self-inflicted torture with literally no incentive," says one social media user. "Give me my in-flight wi-fi, my sleep mask and let's throw in some snacks."
Others doubt whether all of the people posting about their 10-hour flights really have stuck to their self-imposed rules.
And some who have tried raw-dogging themselves haven't come away impressed.
"Big mistake," says a user on TikTok called Brenda. "Pretty sure the only thing that took off was my sanity.
"Note to self, won't be doing that again. Definitely an overrated experience. Not at all enlightening as people make out."
- This story was first published by the BBC