When Turia Pitt was in hospital recuperating from burns to 65 per cent of her body she told her family she wanted to do an ironman one day, despite being told she would never run again.

On Sunday, the 28-year-old took another step in her remarkable recovery by competing in her first ironman triathlon.

Under drizzling rain Pitt lined up with 1400 other athletes for a punishing 3.8km swim, 180km bike ride and 42.2km run in Port Macquarie, on the NSW Mid North Coast.

Pitt completed the swim in one hour and 16 minutes, putting her in 18th place for her age group of women aged 25 to 29 and 170th place for all women.

Just before 4pm, she had completed 180 km bike ride in a time of 7 hours and 13 minutes, and had moved up one place in her age group. She is now in the early stages of the 42.2 km run.

On Friday, Pitt said she was motivated by the desire to prove she is fitter now than before the devastating ultra marathon through Western Australia's Kimberley region in 2011 when she got so badly burnt.

Caught in a fast-moving bushfire, doctors gave her the only slimmest chances of survival. She ended up spending 864 days in hospital, enduring more than 100 surgeries, had fingers amputated and had to learn to walk again.

"What gets me out of bed is just getting back to that really compelling reason of why I wanted to do ironman – just to prove that I'm fitter now than I was in the ultra marathon," she said.

Incredibly, the inspirational speaker and author says her quality of life is higher than before the accident.

"People never know what they're going to do in a situation until they're put in it," she said.

"Some people might have given up, some people might have gone on to live a great life. I think my quality of life now is probably even a little bit better than it was before the fire."

Pitt says she discovered just how strong she is through dealing with her injuries.

"It was tough at the start when I had to rely a lot on my partner Michael," she said.

"My self-esteem has always been closely tied with my physical abilities, so when I couldn't do anything I felt like s---.

"Now that I'm back running and playing sports and swimming I feel more like me.

"What will get me through is just thinking about things in my life that I'm grateful for. Grateful to be able to experience the day, grateful for Michael, for my mum, for this beautiful country we live in and grateful that I'm still alive and can still experience the day."

Tim Reed won the men's event with a time of eight hours and 16 minutes followed by David Dellow six minutes later.

Australian Beth Gerdes was the first woman to finish in a time of nine hours and 10 minutes, followed by New Zealand's Michelle Bremer three minutes later.

An Olympic or standard distance triathlon is a 1500 metre swim, 40 kilometre bike ride, and 10 kilometre run.

Whatever her result, it will be an achievement for Pitt who will then spend three weeks recovering before she heads to PNG to walk the Kokoda Track as part of her role as an ambassador for charity Interplast, which provides free reconstructive surgery to people in the Asia-Pacific.