She began exercising one day in 2010, a 250-pound coed jogging around the campus at Salisbury University.

“It wasn’t a pretty sight,” Kelly Sorensen said. “People made fun of me, shouting, ‘Run, Forrest, run!’ But I didn’t give up; it’s not in my DNA.”

Seven years later, she’s still at it. On Saturday, Sorensen — now a trim 125 pounds — will compete in two races in the Baltimore Running Festival. At 7:30 a.m., she’ll run the 5K; two hours later, the 27-year-old New Windsor woman will tackle her 10th half marathon. Both times, as she crosses the finish line, her headphones will play the song “What A Wonderful World,” by Louis Armstrong. It’s her mantra.

“I am a runner,” she said. Want proof? The Runner’s Prayer is tattooed on her ribs: “Run by my side; live in my heartbeat; give strength to my steps.”

Last year, she ran the Marine Corps Marathon, her first, completing the race in 5:50:36. That Sorensen has made such strides in life boggles her mind.

“Sometimes I think it’s unbelievable where I’ve come from,” she said. “If you’d told me back then how tiny I’d be, or that I could run 26 miles, I’d have laughed in your face.”

Once, Sorensen wore size 16 pants; now, she’s size 3. She can fit both of her legs into one leg of her old jeans.

“Friends I knew then can lift me up now. Before, they wouldn’t have tried,” she said. “Kids at Liberty High School made fun of me being overweight; I wasn’t the girl guys came up to. Funny, now those guys feel the need to talk to me.”

Back then, Sorensen concedes, she hardly helped herself.

“I hated running,” she said. A catcher on Liberty’s softball team, she would excuse herself from those pregame jogs around the field, saying, “Sorry, coach, I’ve got to warm up the pitcher.”

In college, homesickness and stress from studies triggered eating binges.

“I sat in my dorm room and ate chips all day,” said Sorensen, who gained 50 pounds in one year. Then a physical exam brought troubling news: she was both prediabetic and suffering from prehypertension.

“That was my wake-up call,” she said. And while she remembers that first trot around campus, and all of the hoots and catcalls, she’ll not forget the high she felt upon finishing that one-mile run.

“Yes, I was sore, my legs hurt and I thought, ‘Why the hell did I just do this?’” she said. “But at the same time, having done it was amazing — the best feeling in the world.”

She stretched her runs and stuck to her regimen. By 2011, her senior year, Sorensen had shed 75 pounds — enough, she felt, to enter a 5K in Howard County.

“I had doubts, and it took me 40 minutes, but when I crossed the finish line, with my parents cheering … words can’t describe it. I’d set a goal and it was all me. That’s still my most special race.”

Those who know her aren’t surprised by Sorensen’s success.

“She’s one of the few I know who are so genuinely driven and positive that, no matter the challenge, she’ll see herself through,” said Courtney Deppe, 25, of Elkridge, and a friend since college. “Even hip surgery five years ago didn’t slow her down. She didn’t flinch. She always finds something else to push her that much farther.”

In 2014, Sorensen ran her first half marathon in Baltimore (2 hours, 35 minutes) and has done it every year since. Saturday is her first attempt to run two races the same day. The reason?

“Just to say that I did it,” she said. “While running, there’s nothing I can’t achieve. I feel untouchable. No one can hurt, bother or tease me. Running saved my life.

“I have a choice of whether to live a healthy lifestyle — and that’s what I’m going to do.”

It also helped her cope with the death of her brother, Scott, who died of cancer at age 9. She was 3 at the time and never got over his death until she began to run.

“Running allows me to think things out,” said Sorensen, the office manager for a contracting firm in Burtonsville. “I realized that while Scott wasn’t here physically, he was with me on every run. I talk to him, at times. When I feel like giving up [in a race], he’s there. His strength is my strength. He’ll be with me on Saturday, too.”

mike.klingaman@baltsun.com

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