ith three-quarters of his left quadricep torn from his leg, medicos were initially unsure he would walk again, let alone run. Let alone perform any of the surf manoeuvres the Kiama pro-hopeful lived, breathed, woke up for and fell asleep dreaming about.

But almost from day one, Connellan exceeded all expectations. He got back on his surfboard after surgeries and five months of rehabilitation. Later he completed a 100km charity walk and a half marathon, and took up a job that involves regularly telling his story as part of a healthy workplace initiative - Mental Health Movement.

Now, more than five years on, Connellan is training for his first marathon. Gone is the shy and surf-obsessed 22-year-old. Incredibly, Connellan now says that being attacked by a shark was the best thing that ever happened to him.

"When I look back to the time before, my whole life was focused on surfing, which is what you need to succeed in the sport - but I had really shut my mind to other things," said Connellan, now 28.

"With the work I'm doing in the mental health space and the challenges I set myself ... I'm trying to prove to people that you don't have to be happy with the prognosis you were given, you can always do more. I firmly believe if you want to get more out of it, the opportunity's always there."

Connellan credits surgeons and medicos with saving his life and limb, but says others in his sphere - nurses and an influential physiotherapist - Bai Med's Scott Muttdon - drove him to loftier goals.

"I'd decided a couple of months before the attack that I was going to have a proper crack at qualifying for the World Tour and becoming a professional surfer. When doctors were saying I wouldn't surf again, that was my dream being taken away from me," he said.

"Despite the prognosis from the professionals being something that was quite negative, the people I was surrounded with, especially the nurses, kept saying I was young and fit and that gave me the best chance of recovery.

"Scott really helped with some goal-setting and mindset. One of the first things he said to me in hospital was, 'people don't fail from aiming too high and missing. It's from aiming too low, and leaving a lot on the table'. So he actually helped me set those goals and look to surfing again, looking beyond what people told me was possible."

Connellan is intending to paddle the gruelling Molokai to Ohau paddleboard championships in Hawaii next year and is the subject of an upcoming documentary by videographer Sam Tolhurst, of Pyrophytic Film.

He runs as part of a general fitness regime that is necessary to keep his leg strong, but says an influential exchange with Bradley Dryburgh on the Wollongong podcaster's show earlier this year sparked his marathon ambition. Dryburgh, 24, who lives with cystic fibrosis, founded and completed the city's fundraiser 42forCF marathon last year after he spent a prolonged period confined to hospital with complications resulting from his condition.

"He's someone I've learned a lot from, just in my short time knowing him."

"He said to me, 'if you've got an able body you can wake up and decide to run a marathon, but how many people do?'. It really stuck with me. I'm not as able-bodied as I was before, but I am in the position where I could do a marathon."

Feeling particularly spritely after a recent run, he messaged Dryburgh: "could you please do me a favour and message me at around 10am tomorrow and ask if I really want to run a marathon? (I just had a decent run and I'm not sure if it's some sort of high or if I want a challenge)." Dryburgh obliged the next day with a picture from last year's race, with Connellan photoshopped in alongside a question mark.

He has until October 16 to get marathon-fit. After the challenges of the past five years this one, he says, is relative.

"It's just like doing a half marathon, but then turning around and doing it again. So how hard can it be?"