"I had no training, so I trained myself. You have to be careful because the faster you go, the easier it is to get into a slow jog. That is what you have to really watch as some of the races are judged, so you can easily get disqualified."
Purcell has lived in Tauranga for five years but is a local legend in Katikati, where she lived previously.
She walks for nearly two hours, five nights a week, and does 20 half marathons a year. This year she also has four marathons in her sights.
The undoubted highlight of her career so far was completing the New York Marathon in 2011, which she says was an extraordinary experience among 48,000 competitors. Last year she added the London Marathon to her list of accomplishments.
But she says it is frustrating that walkers do not get anywhere near the amount of attention paid to runners at the same events.
"We put just as much hard work into training as runners do and we pay the same amount of money as they do [to enter events], but we are just left behind," she said.
"I would like to see that change.
"If people enter and do well walking, then they know they will be recognised. That is all I am asking. At the NZ Masters Games, which I have been doing for 12 years, they have the marathon walk and run held on separate days."
Next up is the inaugural Taupo Marathon in August, with the San Francisco Marathon her big goal for 2016. "That is the only way I can walk the Golden Gate Bridge."