But Frost never set out to be a mega-marathoner. She entered her first marathon, at Auckland in 2000, only because her then-partner challenged her to do it with him. By the way, he got injured and never ran a single event. Frost hasn't stopped running.
"I have to confess that I'm addicted to the distance. It's the challenge - because you get to a certain mileage and you have to be mind-strong and patient.
"I love that you have so much time out there to just think," she says.
She also loves the sport for meeting like-minded people, for the great places she sees and the camaraderie of being a member of the YMCA run club. Five years ago the club celebrated Frost's 100th marathon achievement. She fits in the events around full-time work for a company supplying food to McDonald's.
To celebrate her milestone, she's raised almost $1600 for the company's charity, Ronald McDonald House, which helps families going through challenging times.
Frost says she has bought more than 70 pairs of run shoes over the years and spent well over $90,000 on events including race entries, travel and accommodation. "It's money well spent," she laughs.
She picked Taranaki to celebrate the mega milestone because it's where she clocked up her personal best race time. She won that marathon (3h 14m 59s) back in 2010. She has won some smaller events too. This weekend will be the 14th time she'll have conquered this event.
Most of Frost's races have been in New Zealand, and she's run some many times, including the Rotorua Marathon 14 times and the Auckland Marathon 15. But she's also run the likes of London, New York and several Australian events.
She's been injured a few times, but has been lucky enough to complete every event she's entered. She's light (55kg) and this helps keep injuries at bay, she says.
Her son Michael, 26, won't be at the special celebration dinner after the race - he's away, but he's proud of her, she says. Her running friends will help her to celebrate.
So what's her favourite marathon outside of Taranaki?
The Lydiard Legend Marathon in West Auckland, "because it's so tough. It sorts the boys from the girls", she says. And yes, she'll be running that again this year.
The numbers
200 marathons. The first woman in Australasia to run this many
8439km in race mode alone
70 pairs of run shoes over the years
$90,000 plus spent on events including race entries, travel and accommodation
