Anne Mahlum built her career by standing out from the crowd.
The 43-year-old entrepreneur — who sports spiky blonde hair, tattoos and six-pack abdominal muscles — launched her boutique fitness chain Solidcore in 2013, and grew it across the U.S. before selling it to a private equity firm in April.
Between the acquisition and two previous investment deals, Mahlum cashed out her Solidcore equity for a total of $88.4 million — and she credits that success to her unwillingness to ever fit in.
"I try to find the uniqueness in things, and then I amplify them … it really has been a huge part of my success," Mahlum tells CNBC Make It. "A lot of times, people try to hide in the herd, and we try to fit in, and I think that's the worst advice."
In Solidcore's case, she took a taxing Pilates workout — which was masked by "cute" and dainty marketing, she says — and turned it into a national brand that focuses on physical strength. Class participants reach second-stage muscle failure while being pushed and cheered on by energetic coaches in blue-lit rooms.
Her mindset was fostered, in sometimes complicated ways, by her childhood home life, she says. At age 16, her parents divorced after her father gambled away their family savings. To cope, Mahlum started running and became hyper-focused on the idea of controlling her own life.
"I didn't want to be hurt ... and I felt like if I can just make an impact, or have a life I'm in control of and empowered [by], that I would escape feeling hurt," she says. "I think a lot of my drive actually came from fear."
Mahlum's hard-charging approach may have helped her build a fitness empire, which now has more than 100 locations across the U.S. It's also brought on legal and professional battles.
Solidcore's first location, in Washington D.C.'s Adams Morgan neighborhood, shuttered after a year due to noise complaints. Mahlum got sued by a former business partner over machine licensing, and again by an ex-boyfriend, who claimed he was a Solidcore owner. Both cases were resolved in mediation, she says.
In 2020, when gyms nationwide suffered, Mahlum laid off multiple employees who'd helped get Solidcore off the ground. Later that year, she was accused of creating a toxic, abusive workplace by dozens of workers in a BuzzFeed News report. The allegations were quickly followed by an employee petition for Mahlum to resign.
In response, Mahlum told her company's board to conduct an independent investigation of Solidcore's culture, she says. She remained CEO until April 2021, and executive chairwoman until exiting the company earlier this year. The experience didn't change her "tough, demanding" leadership style, but it did teach her to balance her drive with boundaries and empathy, she says.
"When we had to do some of those layoffs [I didn't realize] I was taking away [former employees'] social life, their workout life, their friendships, not just their job," Mahlum says. [As CEO], "I had to create an environment that was necessary ... for Solidcore to be successful. But when it ended for people, it was really hard."
Her plan was always to sell Solidcore, she says: Her strength is in bringing concepts to life and building communities, rather than sustaining them over time. The same month she exited the company, she opened her next venture, a New York-based fitness studio chain called Ambition.
To this day, people ask Mahlum if she's surprised by her success. Frankly, she says, she finds the question a little sexist — and she responds by telling them she didn't get lucky.
"I sort of pause and look at them, and I'm like, 'Who do you think has been driving the bus the entire time?'" Mahlum says. "In reality, I had a really clear vision from the very beginning ... and I never wavered from that goal."
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