Rescue helicopter crewman Allan Jefferson is used to putting his body on the line, but he is about to face his toughest test of endurance yet.
The 54-year-old from Townsville has set off to the United States to compete in the Race Across America, which is billed as the "world's toughest bicycle race".
The course spans almost 5,000 kilometres and crosses 12 states from California to Maryland, while climbing 55,000 metres.
The race is about 30 per cent longer than the Tour de France but is completed as a single-stage time trial with no breaks.
Jefferson will have just 12 days to get to the finish line.
"It is a physical challenge but it's also a mental one – I equate it to probably 99 per cent your head and 1 per cent your body."
The experienced multi-sport athlete will be followed by a support crew, who will provide him with food, water, rest stops and moral support across all 12 states.
Crew chief Greg Huppatz, who is also Jefferson's boss, has been planning the intricate logistics of the ride, which begins mid-June.
"Obviously you can't do this in in one hit without some stops, but they will be pretty tiny – a sleep stop might be 20 minutes, half an hour, for the first few days."
The Race Across America, which has been running for four decades and attracts cyclists from across the world, covers terrain from desert to mountain ranges.
"It's gonna be hot, it's gonna be cold, it's gonna be windy, and it's gonna be rainy, and hopefully there'll be a little bit of sun in there as well," Huppatz said
"We know that pretty much we're going to get hit with absolutely everything."
Jefferson attempted the race in 2019 but illness forced him to pull out a third of the way through.
"I got a chest infection, and it put a lot of strain on my body," he said.
This time, he is going in even better prepared – but admits his training regime comes down to "feel".
"Sometimes I'll go, you know what, 30 kilometres is enough today, and other times you go, yeah 300 kilometres is enough," Jefferson said.
During the race, Jefferson will not wear a watch, instead focusing on "little parts of road".
"You get into that zone and it becomes very, very hypnotic," he said.
"The only way that I can tell [what time it is] is when the when it gets goes from day to night and night to day."
The ride is raising money to support the mental health of frontline workers, a cause close to Jefferson's heart.
"I get goosebumps thinking about what it would be like to roll down onto the pier at Annapolis after 5,000 kilometres and go, yeah, I'm done," he said.
