SWIM fast, pedal furiously, run hard. Feel those muscles burning and your lungs squeezing, pleading for air. You feel as though you could die.
Rod Marshdale knows that feeling. Only when he is competing in a triathlon and his lungs are really working, he knows he's alive. He cherishes that feeling.
After all, the 47-year-old was born with cystic fibrosis and is a double lung transplant recipient.
"I know I shouldn't be alive," the 47-year-old says. "I know that I'm alive because of a donor and an incredible health system."
As a child growing up in south-western NSW, Rod Marshdale couldn't do anything without coughing. His parents took him to Sydney, where he was diagnosed with cystic fibrosis, a condition that affects the lungs and digestive system.
In the late 1970s, the life expectancy of a person with CF was 12 years. Rod Marshdale was destined to die young. But he didn't see that as his destiny.
"I just always somehow believed I would live to be in my 60s," Mr Marshdale recalls.
He worked at having a boyhood, playing Australian rules and swimming. He made it into adulthood, married and became a father to two boys. He kept himself as fit as he could, walking and swimming. But Rod Marshdale also spent a lot of time in hospital.
On his 40th birthday, from his bed in Royal Prince Alfred hospital in Sydney, he sent out a message of self-motivation: "70.3 is mine".
That number refers to a triathlon race, the Ironman 70.3, where competitors complete 70.3 miles, or 113 kilometres. The event comprises a 1.9-kilometre swim, 90 kilometres on a bike, and a 21-kilometre run. Those numbers add up to a formidable test for even the healthiest of lungs.
"I couldn't do one back then, but I'd dream that somehow I'd be able to," Mr Marshdale recalls.
The dream seemed impossible. He almost died in 2013, transferred by the Westpac Rescue Helicopter from Taree, near his home at Forster, to John Hunter Hospital. But even if his body was giving up, Mr Marshdale wasn't about to.
In 2015, he was given new lungs and, as he puts it, "a new life". In a voice filled with emotion, he remembers that moment after surgery when he breathed in: "I never knew that much air could exist."
Rod Marshdale told the medical staff what he would do with all that air. He would realise his dream and compete in an Ironman 70.3 race.
"They said, 'Yeah, Rod, go for it'," he recalls. "They thought I was mucking around. I wasn't."
Rod Marshdale competed in his first triathlon in March 2018, achieving a time of 3 hours, 36 minutes. He was on the road to his 70.3 dream, and, while he didn't know it then, to a new life in the Hunter.
Last year, he contacted the rescue helicopter service to say "thank you" for saving his life in 2013. Rod Marshdale got talking to the helicopter service's CEO, Richard Jones, who then spoke with his friend and managing director of Quarry Mining, Kari Armitage, about helping get this bloke his own triathlete's suit.
Ms Armitage, herself a triathlete, not only gave Mr Marshdale a suit, she helped him enter the Maitland Triathlon in November. He has since competed in a string of triathlons, wearing that Quarry Mining suit.
"He's inspiring," Ms Armitage says. "He's so grateful he's got this life to live."
Quarry Mining's marketing manager is elite Maitland triathlete Peter Hodgson, who is now training Mr Marshdale and, like Ms Armitage, has become a firm friend. Both have helped Rod Marshdale move to East Maitland, which puts him closer to training.
"Some might whinge about how hard [a triathlon] is, but he doesn't," says Mr Hodgson. "He does it with a smile on his face."
As Rod Marshdale says, he knows how far he has come in life by even being able to compete.
"At my worst, I was getting 600ml of air in total in and out of my lungs," he explains. "After my transplant, I was getting over six litres. Ten times the amount of air."
Now Rod Marshdale is preparing to live his dream. In May, he will go to the Ironman Australia event in Port Macquarie to compete in the Ironman 70.3 race. To his knowledge, no Australian with CF and having received a double lung transplant has done that event before.
Professor Peter Wark, the director of the John Hunter's Adult Cystic Fibrosis Clinic, says competing in these sort of events would push Rod Marshdale's body. But he didn't try to talk his patient out of competing - "I don't think it would have been possible".
"I think he sees this as a way of controlling the illness, and it probably does him more good than harm," Professor Wark says.
The life expectancy of an Australian with CF is 37 to 38 years, says Professor Wark, and a lung transplant can also bring a host of problems. But, his doctor says, Rod Marshdale is doing very well.
"He's done remarkably well, and he's been on quite a journey," Professor Wark says.
The journey continues. To Rod Marshdale competing is about more than him realising a dream. It is about showing others with cystic fibrosis what is possible. It is about raising public awareness.
And it is a way of saying "thank you" to the donor and their loved ones.
"I've had two lives in one, and I'm a duo competing as one," he says. "I'm a pretty lucky dude really."