Anne Mahlum cannot stay still. It doesn’t matter whether she’s mid-marathon or in her Adams Morgan apartment — she bounds ahead like a finish line is steps away. Even the 32-year-old’s spiky blond hair seems to fly in every possible direction.

This frenetic energy has helped Mahlum run more than just races. About 5:30 a.m. one morning in 2007, she jogged past a Philadelphia homeless shelter and saw some guys outside wave. Mahlum, who had started running as a teenager to cope with her dad’s gambling addiction, realized they reminded her of him. And she had the idea of launching a run club.

The shelter director “tried to think of the nicest way to tell me that homeless guys don’t run,” she remembers.

Six years later, the nonprofit organization she founded, called Back on My Feet, operates run clubs at nearly 60 shelters in 11 cities, including Washington and Baltimore. (The newest branch, Los Angeles, opened Monday.) With a staff of 48, thousands of volunteers and an operating budget of $6.5 million, the organization can boast an even more impressive number: 46 percent of participants find a job, housing or both.

So Mahlum’s announcement in July that she would be stepping down as chief executive was surprising. And her press release in August that she’d be opening a boutique fitness studio in Washington was downright head-scratching.

But it all makes sense to Mahlum, who recognized about 18 months ago that she was growing restless. She pushed to expand Back on My Feet to more cities and developed an employment initiative. All that building led to more work, but no relief. Back on My Feet needed stability, and Mahlum needed a new project.

She found it in January at a studio in Los Angeles that specializes in the Lagree Fitness Method. Developed by celebrity trainer Sebastien Lagree, who souped up a Pilates reformer to create what he’s dubbed the “Megaformer,” the method pairs slow, controlled movements and rapid-fire transitions to absolutely devastate muscles.

“I walked into this class, and I thought, ‘I can run 10 miles without any effort. I’ll be fine,’ ” Mahlum says. This time, she admits, she was wrong. With her abs on fire and her legs shaking, she returned home to New York and told her boyfriend, Brennan McReynolds, he had to try this thing at a Manhattan studio.

“I was shattered,” says McReynolds, 33, who has an Ironman, ultramarathon and countless other endurance events under his belt.

The pieces just fell into place after that. Mahlum and McReynolds had met in the District and were looking for a reason to return. Although more than 100 Lagree Fitness Method studios have sprouted up across the country — and in Canada, Australia and Hong Kong — no one had bought the license yet for the Washington area. In March, Mahlum made a phone call to find out whether she could buy it. In August, Mahlum and McReynolds moved to Washington so they could begin training other instructors.

And on Saturday, the doors officially open at Solidcore at 1841 Columbia Rd. NW.