The physicality of SAS Australia is enough to turn anybody off, but perhaps even more demanding than the freezing cold and terrifying heights is its mental game.
Speaking to Woman's Day, former Love Island star Eden Dally says he was left "haunted" after a challenge that required him to climb over a thin rope suspended high above raging waters.
"I do hate a sob story, but I witnessed a man drowning in the ocean," the 28-year-old reveals.
"I tried my best to save him, almost drowning myself, only to see that the young man couldn't be revived."
"I hadn't ever seen a person die in front of me... that moment, over the rope... it brought back those horrible memories," he adds of the gruelling challenge.
It's certainly a far cry from his time on the dating show that made him a household name.
"Love Island was all fun, sun and margaritas. It wasn't a show that you really take seriously," he confesses. "Prior to [SAS], I had been reading what my grandfather went through during his time in the war. I wanted a small taste of what he experienced."
It quickly became a case of "be careful what you wish for" for the father-of-one, who was left mentally and physically drained by the show.
"I was starving and missing my family. Being away from my son really got to me – there were a few moments where I was well and truly ready to quit," says Eden.
"But I didn't, and I remember [instructor] Ant Middleton really got up me for my pathetic display of wanting to quit."
Worse than the intimidating directing staff on the show, Eden says he was also subjected to some seriously difficult recruits.
"Honey Badger [Nick Cummins] was the most difficult to live with," laughs Eden. "Mainly because he wouldn't stop farting!"
And while the show left Eden rattled, he reveals he's been inadvertently training for the SAS selection process for some time, thanks to his "challenging" partner Cyrell Paule.
The 31-year-old made headlines in 2018 following her fiery appearance on Married At First Sight, becoming something of a TV sensation thanks to her blunt and at times OTT personality, which earned her the name "Cyclone Cyrell".
Eden is the first to admit they've had their ups and downs since meeting two years ago, even separating months before the birth of their son, Boston, now eight months.
But things have thankfully mellowed.
"Boston has changed so much of me!" he says.
"Everyone says how much you need to teach your child, but really Boston teaches me. He taught me how to be a better person and to be more responsible," he gushes, before admitting that raising a child in lockdown has been tough.
"I'm dealing with the two deadly Cs – Cyrell and COVID! If the virus doesn't kill me, then she just might," he jokes.
"As I'm sure it's been for others, it's been hard. We had Boston on February 9 and the pandemic kicked in a month or so later… So being first-time parents with no help, plus lockdown, it was a handful all right."
"Being at home with Cyrell is like living with a cyclone! Like every relationship, we have our ups and downs and we both do each other's head in... though she usually does win all the arguments!"
Since the reality stars went public with their romance, there have been plenty of naysayers who are sceptical of the validity of their romance, but Eden insists they've never been better.
And despite Cyrell being "turned off" marriage after her ill-fated pairing with TV groom Nic Jovanovic, Eden says he's not giving up on the idea of one day marrying the mother of his child.
"Look, never say never," he insists, admitting they'd be more inclined to take part in their own reality series.
"Our own show would be great. I remember I read an article once saying, 'Inside Cyrell and Eden's turbulent romance'... viewers would be in for a rollercoaster ride, that's for sure!"