EVERY time best mates Justin Jones and James Castrission go on an adventure; they get an idea for another one.
The young adventurers decided they wanted to trek to the South Pole while they were in the middle of the Tasman Sea, kayaking from Australia to New Zealand.
They got the idea for that world-record-breaking ocean expedition while they were paddling the length of the Mary River.
"We both just absolutely love the outdoors," Jones said.
"It's been a big part of our focus on life. We started going out on a lot of smaller expeditions and then the trips started to get bigger and bigger."
Their Antarctic adventure, where they made history by completing the longest unsupported polar expedition of all time, is by far their biggest accomplishment to date.
The pair had never even strapped on skis before they started preparing for the trip.
"James and I love the aspect of going out and immersing ourselves in a topic or field we don't know too much about," he said.
"It's extremely exciting. You're constantly pushing the boundaries.
"People might say we're slightly naïve, but in our preparation and planning we uncovered all the things we needed to know."
Pulling sleds weighing more 100kg, without the assistance of a dog sled team, and living in subzero conditions took a brutal toll on their bodies.
During the 89 days it took them to ski 2275km from the Antarctic coast to the South Pole and back they lost a combined 55kg of body weight.
"It was right on the limit of what was possible, maybe even a little bit too far," Castrission said.
Jones added: "The hardship was constant for three months. The cold and the wind pierced every single cell in our bodies".
They also filmed their three-month journey, and the result is a documentary that will air on Nat Geo Adventure this week.
But the mates were not just in a battle with the elements and their own bodies.
They were also racing Norwegian Polar veteran Aleksander Gamme, who was attempting to set the same record by himself.
The documentary comes to a climax when the Aussies, exhausted and out of food, see Gamme waiting for them to cross the finish line and share the record.
"It was a life-changing experience. That's what adventure is all about," Jones said.
"You try and beat one another, but a higher level can be reached when you do it together."
As you would expect, the thrill-seekers already have another epic expedition in mind but they're keeping mum about it for now as Castrission is expecting his first child.
"We have a few ideas but for the moment we're keeping them under wraps," he said.
"They (the trip and having a baby) both involve sleep deprivation though (laughs)."
*To win one of four signed copies of Castrission's book Extreme South, email your name, address and telephone number to firstname.lastname@example.org by noon AEDT on Thursday, December 13.