The 38-year-old accepts she has a genetic disposition to wear muscles as a female so she's already half way there.
"I felt I looked more a like a girl in a fitness magazine than a girl on a catwalk magazine so I thought I'm going to give this a go because I won't be six foot tall and 45 kilos."
She's a fulltime mum of 10-month-old Claudia, Catalina, 6, and Geovanna, 8, who helps athletes on the side at the Nfinite Fitness and Health gym, which also sponsors her.
In her 20th year of bodybuilding, and with a decade of competition behind her, she only reignited her passion for the sport 16 weeks ago for fun after her third child.
But the returns were more rewarding than she had anticipated so she thought, why not get back on the competitive platform?
Today Parr will strut her stuff at the NABBA/WFF Pan Pacific Pro Championship (amateur) in Ellerslie, Auckland, where 22 pro cards up for grabs, giving athletes eligibility to professional events overseas.
She'll compete in the 30-plus sports model (bikini/sports) rounds. It's her first time at the champs as a competitor although she was a "test" (apprentice) judge there from 2014-15.
"It would be nice to get a pro card - I'll be up against some stiff competition - but I won't be disappointed if I don't get one because I'm just happy to get to where I'm at."
Over the years, Parr has got a mixed response from others in the sport, not that it ever had an impact on her resolve. She does see the humour.
"I was in a dairy once and a guy behind me asked if Arnold Schwarzenegger knew that I had borrowed his legs."
A grinning Parr takes that sort of ribbing in her stride but recalls that, in the early days, she shied away from sleeveless tops for fear blokes would slip on their sweatshirts if they saw her.
"I think as you spend more time in your sport and you get more comfortable with yourself, you don't mind what other people say, as long as you're happy."
The daughter of retired swim coach Noel Hardgrave-Booth also dispels any suggestions that the bodybuilding types tend to flock together. In fact, most of her friends aren't into it.
"These days people are more accepting and they admire it, especially after having children."
Parr wants to be that walking, talking poster for her children and inspire other mothers.
"I want them to know it's not all over just because you're over 30 or because you've had a few babies, as you can do some great things with your body."
No doubt motivating them to embrace a healthy lifestyle is paramount to how good they'll end up looking in a bikini.
In bodybuilding it was a hard graft with training and "harsh dieting" but in the sports model category, she only does half-an-hour of weights three times a week.
"I'm naturally muscular but other people might need [weights]," she says, adding she does cardio training for 30 minutes four to five times a week.
Consistent "clean dieting", devoid of refined sugars and dairy goods, is on the agenda.
"I generally have a lower carb diet but I increase my good fat to eat things like coconut oil, avocado, salmon, tuna and chicken with occasional red meats, as well as vegetables two to three times a day."
She has a "cheat meal" once a week to have whatever takes her fancy such as wicked wings and chocolate.
Parr isn't averse to junk food but will have it in moderation.
A 100m, 200m representative sprinter, the former Taradale High School pupil was introduced to weight training. It struck a chord straight away.
"I found I enjoyed the weight training and lifestyle for bodybuilding from a young age," says the former Greenmeadows School pupil.
Week in, week out she could see the incremental improvements on her body and, as a female, it made her feel stronger.
"When I was young I was encouraged to do pageanty-type of stuff which I was really averse to because I don't think being born looking good is something to be celebrated, as it's a genetic forecast.
"I liked bodybuilding because it wasn't about being pretty. It was actually about being cranky."
On the other hand, she found males also accorded her more respect as a muscle-bound female.
Having achieved a lean, mean appearance in 2013 she yearned for more and that's when the sports model category beckoned.
"I don't just want to turn up looking the same every year. I wanted a new goal and the challenge of being able to manipulate my body into a shape, especially after having three children."
She does it for herself rather than public endorsement.
The emphasis on bikini/sports model is still the body but it doesn't hurt to have an alluring face. Athletes tend to have the propensity to grace the glossy cover of a fitness magazine but "more mainstream".
"So there'll be no big veins, not really ripped and not too dark on the tan - a bit more mainstreamy and a little more girly."
A hardcore bodybuilder, she finished third at the Southern Hemisphere Championship at the Gold Coast in 2013.
In 2002 she was world champion in the shape class at Tenerife, Spain, and runner up at the Nabba Universe a week before that in Alicante.
Parr, who is organising the Nabba/WFF Art Deco Grand Prix at the Taradale High School on September 17, believes bodybuilders are a methodical lot who conceal an alter ego.
"They look quite introverted, shy sort of people but they have a chance to dash into a phone booth and change into a Superman outfit and come out on stage looking confident and showy, even though you're not like that in your day-to-day life."
Social media, Parr hastens to add, has changed the landscape of bodybuilding quite significantly in the past few years.
"We have a lot of people who don't actually compete but they have athlete pages so it's more about getting attention."
Parr considers herself a purist.
"I put my hobbies on my page but not my pictures. I do my stuff on the stage, not on social media," she says, encouraging her athletes to maintain a sense of privacy to make people buy tickets to view their sculpted bodies.
"That's just my opinion, so people who do that are fine but that's just not how I roll."
She isn't about to end her love affair with the sport any time soon although she stopped exercising altogether during her pregnancy.
"I'm terrible. I know there's benefits to it but I can't be bothered. If I can't challenge myself I don't want to do it."
Mark Anderson, of Nelson, a Masters Universe champion, and Johanna Mountforte, of Auckland, a WFF professional, will be here to promote the Bay event.
The Art Deco event is in its second year and will start at 1pm with "Bertie" (John Cocking), a 70-year-old bodybuilder, hosting it.
"Bertie looks fantastic, you know. He looks almost 20 years younger than what he is."
Tickets to the Art Deco event are available at the Nfinite Health and Fitness gym in Napier.
