But an insensitive comment about her body from a man got Bergenfield mother so angry that she took to scaling a beam in the gym.
A comment similar to that of the one at Retro got her moving is the one that got her moving five years ago.
"One of the things I've noticed about myself, and most women would, is that we can do a lot more than we think we can," Hart said.
"We can do hard things, we can do weird things and we can do fun things. The 'I can't' is in our heads."
It started in 2011 when Hart was sick and tired of hating her body.
"My husband gave me an option," said Hart, a middle school Spanish teacher in Teaneck. "I could either stop complaining about my body or start working out and keep complaining."
She chose fitness.
The athlete spent her first year in the gym walking on the treadmill before wandering into foreign territory and lifting weights.
The movements became increasingly more unorthodox and Hart noticed a change in her body and confidence.
Two years and a half years ago, Hart ran her first obstacle race.
She won the Vikin Double obstacle race over the summer and came in 10th at the Civilian Military Combine in September in Brooklyn.
Most recently, Hart was an American Ninja Warrior course-tester and raced the Obstacle Course Race World Championship.
"Grown-ups don't get to have much fun — and this is fun," the mother of two said. "If time was no concern I'd train all day."
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