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Katie Peters photographed at The Orient Country Store by David Benthal.

Katie Peters has always led an active lifestyle. Growing up in Orient, she said, it sometimes felt like being outside was the only thing to do. 

“We felt like we were locked at the end of the world, but looking back it was pretty good,” she recalled.

She loved to run, jump and climb with her two brothers and two sisters — she’s the middle child — and she fell in love with soccer at an early age. 

But it wasn’t just the game itself that kept her playing on travel teams in high school and club ball at Syracuse University. It was her teammates.

“That was always my second family,” Peters said. “I’m still friends with them from so many stages of my life.”

As it turned out, that sense of family and community she got from playing sports would lead her to pursue an unusual career path as a fitness trainer, owning her own studio, Underground Training in Southold. 

Peters’ initial goal was to work in education and she earned a biology degree from Syracuse followed by a master’s in education from Long Island University.

While attending LIU and working at a doctor’s office and later in a government job, she began to take fitness classes like spin and TRX. Soon, she went from student to teacher, earning her personal training certificate and teaching classes on the weekends.

“At first it was very intimidating,” Peters admitted. “People you were used to sweating next to were looking at you to get their workout in.” She would soon grow to love not only the role but “the challenge of creating something that people were struggling through — in a good way — that made them want to show up every week to my classes.”

And while the teaching gig always seemed hard to come by, training came naturally. Even just hanging out with her friends started turning into fitness classes.

“My group of friends would come to my basement, and I’d teach them a class,” Peters said. “They’d say, ‘Oh, I love this’ or, ‘Oh, you could do more of these.’

“My husband and I had a conversation, ‘Is this worth it?’ I left my government job and started this.”

Peters opened her Southold location in 2017 and now offers classes including TRX, “bells and beats” (which includes kettlebells and music) and a low-impact body sculpt. Talking to Peters, it’s clear her road to Underground Training is a tale of strength and flexibility.

The first year was something of its own sweat session, complete with the doubt and endorphin-induced joy that come with a challenging workout. 

“It was horrifying and really awesome all at the same time,” she said. “For someone who doesn’t have a business background, it was a lot of learning on my feet, asking for feedback and putting that into action … it was a big eye-opener.”

Peters persevered, in large part because of her friends and an even larger community of women who have continued to come back for another class full of reps, challenges and rewards.

Peters’ classes are about empowerment. (Credit: David Benthal)

“I love hearing people say they are feeling stronger and the things they can do as opposed to what they couldn’t do,” Peters said. “Not just, ‘I’m this size now.’ That’s what I really focus on. One woman, she’s older, 75 or 76 now, and she can lift her arm up higher than she’s ever been able to.”

Peters’ classroom style reflects that mentality. Where some instructors may focus on “burning off that weekend barbecue,” she takes a more positive approach. 

“You’re not here to punish yourself for what you did or ate,” she said. “You’re here to show yourself what you can do and what you can do next. It’s always structure and function. If you couldn’t do a box jump four weeks ago, maybe you can do one today.”

Peters has her eyes on some lofty goals, too, perhaps moving into a larger space and hiring additional trainers. Currently, she’s the only teacher other than a few yoga instructors. But even if she hired extra staff, she doesn’t see herself giving up teaching anytime soon.

“This is what I want to do,” Peters said. “I’m just excited to offer new things and do something different on the North Fork.”