In junior high school, she ran cross-country and track, and in high school she played soccer. The first in her family to attend college, she earned a degree in information systems from Penn State. She met Jim, a nice Irish lad and North Catholic grad from Frankford, at a conference in 2005.
For 10 years, Jim, 33, a computer programmer, was a smoker. But on the day he married Sophorn, he quit cold. His bride had made it clear that his continuing to smoke was, in his words, a "non-option."
As often happens when one stops smoking, Jim began to pack on the pounds. Unhappy with his growing chubbiness, he decided to train for the 2009 Broad Street Run. His Uncle John had run it and finished, so why couldn't he?
To make things more interesting, he dared his wife to run as well. Sophorn embraced the idea, and the couple trained through the winter and spring.
During that 10-mile race, "she abandoned me," Smiley reports with a grin. She finished in one hour and 33 minutes, a full eight minutes ahead of him.
Flush with success, she dared her husband to try the Philly half-marathon the following November. He nipped her by two minutes in that 13.1-mile contest, but no matter. By then, Sophorn was hooked on long-distance running.
"I really connected with it," Sophorn says. "When I go out for a long run, it's my time to think and contemplate. It keeps me at peace."
Five days later, she announced, "We're doing the Philadelphia Marathon next year."
They joined USA Fit Philly and trained with that spirited group and its helpful coaches over the summer. In November 2010, both completed the marathon, Sophorn in 4:25, Jim in 4:42.
Through USA Fit Philly, they met ultra-running enthusiast Pete White, 48, of Media, who took them under his wing, serving as their coach and mentor. When White participated in last spring's Philadelphia 100 Endurance Run (12 laps of the 8.4-mile Schuylkill Loop), Sophorn paced him for a couple of laps. The idea of running an ultra began to appeal to her. When White encouraged her to try the John F. Kennedy 50-Mile Run, "it definitely sparked a light," says Sophorn.
"Sophorn is as determined a runner as I've ever seen," says White, who praises her for her singular focus and being very coachable. "She believes in herself and she'll let nothing get in the way of a goal she knows she can accomplish."
The JFK 50-miler took place last month, on the Saturday before the Philadelphia Marathon. The horseshoe-shaped course in central Maryland includes about 13 rocky miles on the Appalachian Trail and about 26 level miles on the Chesapeake & Ohio Canal towpath, which parallels the upper Potomac.
Sophorn, who less than three years ago had never run more than five miles and who sustained a hip-flexor strain while training, still finished the 50 miles in 10 hours and 38 minutes.
"I had a blast," says Sophorn, 32, who works as a systems analyst for the Navy. "It was a great race and a great course, and I was surprised at how good I felt mentally and physically. I didn't find it hard at all."
Sophorn especially loved the Appalachian Trail portion of the race, and she made the 50 miles more manageable by breaking it down into four- and five-mile chunks. On the towpath, she conserved her energy and strength by alternating between running and power-walking.
"I enjoyed it all," Sophorn says. "Every mile, I was just happy to be part of it."
"She cruised through it," says Jim Smiley. "I'm in awe of her."
Her twin sister and in-laws came out to cheer her on, but she was especially buoyed by the presence of her mother, Khanny, who gave her a hug at Mile 38.
"I run in homage to them," Sophorn says of her parents. "I think of the distance they traveled and the hardships they experienced trying to escape the war. Every holiday, they tell the stories - about how my father was jailed and tortured, about hacking through jungles with land mines and dodging enemy soldiers, about being malnourished, near death from dysentery, and begging for food.
"Running gives me a connection with my parents and our shared past, but even the most difficult endurance race is nothing compared to what they went through."
"Well Being" appears every other week, alternating with Sandy Bauers' "GreenSpace" column. Contact Art Carey at email@example.com. Read his recent columns at www.philly.com/wellbeing.