This Founder Created the Fitness Mirror While Pregnant—and Sold It to Lululemon for $500 Million

Back when gyms were allowed to open at full capacity and boutique fitness classes were like social events, Brynn Putnam, founder and CEO of Mirror, was already thinking of ways to elevate her workouts at home.

"I always felt like working out at home and you were sacrificing quality for convenience," Putnam tells CNBC Make It. "You were putting a big bike or a treadmill into your small in your apartment, or you were searching for content on YouTube and watching it on a tiny phone while you tried to awkwardly workout."

So Putnam did something about it. She created the Mirror, a "nearly invisible" smart, tech connected mirror that allows users to stream workouts and fitness classes from home, while watching themselves work out. All for $1,495 for the equiptment and $39 a month to access the content.

But that's not all — Putnam did it all while pregnant.

In June, Lululemon bought Mirror for $500 million, and Putnam, now 37, stayed on as Mirror's CEO.

Here's how she created a multimillion-dollar business with a baby on board.

Imagining a better home workout

In 2016, Putnam, was "newly pregnant and dealing with really bad morning sickness," she says. Getting to a fitness studio was becoming logistically difficult.

"Making a reservation, walking 20 minutes to my studio, working out with other younger, more athletic people, just was no longer working for me personally," she says.

Putnam had been a professional ballet dancer with the New York City Ballet since she was 16, and when she retired she created the high-intensity interval training exercise class Refine Method and its New York City studios in 2010.

"So, I started to think about how to take what I created in real life and translate into in home," Putnam says.

For example, at the studio instructors wrote workouts on white boards, used a stopwatch to keep time and gave attendees real-time modifications or ways to make exercises more difficult.

"They stood at the front of the room and inspired people to to be their best," she says.

As an elite ballet dancer, Putnam had spent most of her life in front of mirrors. But it wasn't until she surveyed Refine Method members that she realized a mirror was the perfect "vehicle for putting all those pieces together," she says.

Visual feedback that clients got from watching themselves work out created "this incredible, real energy loop that inspired them to work harder," Putnam says.

So why not use that to virtually stream workouts?

Pitching to investors while 9 months pregnant

By the time Putnam was pitching investors on Mirror, she was nine months pregnant.

"It was very nerve-wracking to be a single female founder with no technical skills, presenting a prototype that looks beautiful but was really not functional while very pregnant," she says. (Putnam's husband, an engineer, made the prototype.)

Some investors and entrepreneurs suggested that Putnam find a co-founder, one who was male and had technical experience, and recommended that she wait until after her pregnancy to fundraise.

"You sort of learn very quickly who are the investors who understood the vision and those who definitely do not," she says.

Putnam didn't budge: "I felt really strongly that we had a really great product and that the market was ripe for the opportunity," she says. "I didn't want to miss my chance with my first business."

Looking back, she says that she "dodged bullets" by losing some of those investors. "If we had brought those partners around the table, we would never have had the freedom to build the company that we built today," she says.

Pumping and scaling

On the day Putnam's son George was born, she signed her first round of seed funding, which was $3 million from First Round Capital, right from the hospital. Within two weeks, she returned to work, breast pump in hand.

Mirror's first round of funding went toward designing and developing a functioning prototype (with hardware, software and content) that could then move into mass production and launch, Putnam says.

Two years after closing the first fundraising round, Mirror launched in 2018. In Mirror's second year of business, it did $150 million in revenue with a team of 125 people. By 2019, Mirror raised a total of $72 million in outside investment.

In September. Lululemon bought the company for half a billion dollars in cash, which has allowed Mirror to scale "much faster with much greater certainty," Putnam says. "I think Lululemon and Mirror together is a case where one plus one equals five. So the the upside potential for both companies is really limitless."

Both her babies are growing up.

"There are so many times when you're making choices between your baby and your business as a mom and a founder that are heart-wrenching," Putnam says. "It's been important for me to remind myself that my son will hopefully one day wake up and look at me and be proud of what I built, and feel inspired that he can build anything that he wants to build too."

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