With a broad smile across her freckled, sun-kissed face, blindingly white hair and a running skirt, New Zealand's Anna Frost has been the most easily recognizable ultrarunning competitor—and one of the few female trail runners making a living from the sport.

And so it was just as obvious when Frosty, as she is best known in ultra circles, vanished from the scene in 2013. She could blame her absence on injured shins, but she was less able to explain the psychological issues that were preventing her from getting back to the trails.

"I was traveling a lot, not resting, putting too much pressure on myself, and it really turned into a mental thing," Frost says, during a fall training stint in Flagstaff, Arizona. "When I finally was just unable to run, I got really low and started thinking, 'Who am I, then, if I'm not Anna the Runner? Then I'm no one. What will I do? What will people think?' "

In that depression, Frost spent six months putting on weight, neglecting sleep, living off coffee and partying a lot. She got back home and realized, "It was crap, what I had done." She spent the next two months breathing. And that was about it.

"As soon as I started repeating mantras to myself—that I was enough as I was; that running was what I did, but I didn't have to do it—the injury started going away," she says. "My physios took out all exercises, and we just focused on deep belly breathing and stretching out through my neck. Just breathing."

When her friends and fellow ultrarunners Lizzy Hawker and Mohamad Ahansal invited her on a fastpacking trip in Morocco, Frost went with the intention of walking. But that naturally turned to running. And then she found herself in Nepal, where she joined a 15-day stage race. Carrying almost 20 pounds on her back, with a map and no commanding knowledge of the language, Frost was rejuvenated.

"These people in Nepal have absolutely nothing but a whole lot of love and family and friends--and they're willing to share that with you," she says. "You're up at 4,000 meters and it's another 4,000 meters above you; you're the size of a pea, and I find that incredibly empowering. It was the most challenging thing I've ever done, physically and mentally."

So, in February, Frost felt it was time to return to the racing circuit, starting in New Zealand. She eased in with no expectations other than to stay fit and healthy. She headed to the Transvulcania 52-mile race in the Canary Islands (where she won and broke the course record), then to Chamonix, France, where she trained with Emelie Forsberg for the Mont-Blanc 80K in June. (Frost placed second to Forsberg.) Then it was on to the U.S., where she claimed victories at the Speedgoat 50K and the Telluride Mountain 50K, placed third at the Rut 50K and paced Kilian Jornet to a course-record-shattering win at the Hardrock 100 in Colorado.

&Published: Feb 24, 2015 11:09 AM EST.

With confidence and dreams of entering Hardrock herself one day, for which runners need to qualify with another 100-mile race, Frost sought out a new challenge in September. She entered her first 100-miler at the Bear, in Logan, Utah. She won and broke the course record by 16 minutes.

"I really enjoyed it and was lucky to not ever be in a dark, deep zone," she says. "It is not my new distance, though; I just really wanted to qualify to run Hardrock—I want to do that one because it's a totally different atmosphere, a nice vibe, still a pureness to it."

By October, Frost was recovering and easing back into training in Flagstaff before heading home to New Zealand (and more summer), where she'll focus on swimming, making jewelry for her online shop and catching up with friends and family. It's a time she's come to enjoy—a time when she's learned to ignore that call to the mountains and to be somebody other than Anna the Runner.

"I've taken a totally different approach, and it's much healthier. It was a hard process to go through, but rewarding as well," she says. "It taught me to believe in myself and not in what I do."