The 55-year-old mother of two grown children has been competing in the annual race since 1980. But her goal is not to be victorious -- just to remain healthy.
"I am not a speed demon. I want to start strong and finish strong," said Mandell, who lives in Wyncote, and is the director of lower-school admissions and enrollment management at Springside School in Chestnut Hill.
"I want to be in shape, I want to keep healthy, and I want to keep running. I don't care about my time."
That attitude is a far cry from her early 30s, when Mandell obsessively ran from eight to 10 miles a day in the effort to get better and better. Now, years later, she believes that moderating her workouts can keep her in the running for the long haul.
Mandell has also taken up long-distance biking, and last year traveled to Israel to take part in a grueling 250-mile ride from Jerusalem to Eilat, an event that raised money for the Arava Institute for Environmental Studies, located in southern Israel.
That trip was the first time that Mandell and her husband, Herb -- who also works hard at keeping in shape -- had been to Israel. They now found themselves waking at 6:30 a.m., hopping on their bicycles and pedaling across foreign cities, towns and desert roads until 5 p.m.
"It was an extraordinary physical challenge -- not just the biking, but the conditions of the desert," said Mandell, who completed the ride with 106 other cyclists, including her husband.
"You have to drink a liter of water every hour so you don't dehydrate."
Perhaps a testament to her physical and mental toughness is Mandell's demeanor as she approached some of the steep hills that lined parts of her journey.
"You take a big drink of water, you take a deep breath, then you look down while you're pedaling. You do not look at the hill, because if you look at the hill, it's demoralizing to see what lies ahead," she explained. "It's a biker's trick. Just take it one revolution at a time, and you get to the top."
When she returned home, Mandell, inspired by her visit to the Jewish state, felt compelled to take on another challenge -- this time, the mental and spiritual task of becoming a Bat Mitzvah.
Mandell enrolled in adult-education courses at Or Hadash: A Reconstructionist Congregation in Fort Washington, and initially acknowledged having some difficulties adjusting to the language.
"I didn't know a word of Hebrew," she admitted, "but to not do it would be to be incomplete in some way."
After eight months of attending classes and services, she celebrated her big day this past June -- June 24, to be exact.
Her rediscovery of Judaism has given Mandell a new respect for her other passion in life -- running.
"For me, running is a form of prayer," proclaimed Mandell. "When I run out of doors, I feel very connected to my spirituality and to nature."