Hours after chairing a Planning Board meeting, Gary Trendel laced up his running shoes for a 3:45 a.m. run, training for his first Boston Marathon before heading to work.

Trendel is running on behalf of One Summit (onesummit.org), a North Andover nonprofit that pairs pediatric cancer patients with Navy SEAL mentors. The program, which instills a sense of determination in these young people, mirrors Trendel’s tenacity in achieving his personal health goals and support of his mother, a nearly 40-year cancer survivor.

Living just over a mile from the Boston Marathon start line, Trendel explained that the race has always been inspirational for him.

“Every single person running has a story in this massive event,” he said. “And every year, when I would watch the runners at the start line, I would say, ‘Maybe next year.’ ”

Trendel previously ran his first and only marathon in 1999 when he participated in the New York City Marathon. What has held him back from running the Boston Marathon over the years were concerns about his weight. Over the past eight years, Trendel has incorporated running and cycling into his lifestyle, shedding 80 pounds as part of his journey to “be in the best physical health of my life.”

Trendel is using his increased fitness to run for One Summit. He directly experienced its impact on young people after one of his best friend’s sons was diagnosed with a brain tumor.

“Pairing Navy SEALs with pediatric cancer patients inspires them to have the grit in overcoming insurmountable obstacles,” he said. “While One Summit has allowed [the friend’s son] the ability to grow up like a normal kid, he and his siblings have benefited from their support. People don’t often think about the support that family members of cancer patients need, particularly the psychological impacts.”

Trendel stressed that while his friend’s son still is fighting, “He is living a healthy and active life” thanks to One Summit.

Added Trendel: “It’s about resilience, growth and grit.”

Gary Trendel will attempts his first Boston Marathon in a fundraiser for the nonprofit One Summit.

One Summit stresses experiential learning, storytelling, community engagement and mentorship. The nonprofit is hosting an upcoming rock climbing event called Climb for Courage with patients and their mentors. One Summit runs these events in Boston, San Diego, New York City and Virginia Beach. The SEALs guide their mentees through a curriculum based on teamwork, goal-setting and overcoming adversity. They then encourage the patients’ rock climbing wall exercises, cheering them on as they persevere toward their goals.

“My understanding is that it’s very emotional and really touching,” said Trendel.

Another motivating force for Trendel to run has been his mother’s cancer battle. He discovered at age 9 that she was diagnosed with a rare form of bone cancer.

“I also understand what it is like for a child to have a loved one fighting cancer,” he shared. “I know how hard it is for a family to cope with the diagnosis.

“We had amazing support from our friends and community,” continued Trendel, “and my parents did a great job of shielding me from truly understanding the risks of her diagnosis. But not everyone has the resources and support that we did.”

Nearly 40 years later, Trendel described his mother as “cancer free and thriving.”

While Trendel debated supporting a Hopkinton-based charity with his run, he decided to lend his support to One Summit (givengain.com/project/gary-raising-funds-for-one-summit-inc-67570) because of its direct impact on cancer patients’ lives and because it is a “relatively small” nonprofit.

“The first step I took was deciding I was going to run this thing,” he said with a laugh. “I was certainly not fast enough to qualify. What I love about the Boston Marathon is the fans who stick around to cheer for the final runners to cross the line.”

What has kept Trendel focused on his training is the support from friends and the community. While he has been battling minor injuries and receiving physical therapy, he keeps in mind the pain that those with cancer endure as well as the people who have positively influenced his life.

“For me, it’s taken a village,” he said. “This is a journey that I couldn’t do on my own.”

Every day for 26 days, Trendel participates in what he calls “26 miles of gratitude.” He dedicates each mile he runs to a friend, family member, physical therapist or other positive person who has influenced him. He focuses on how they have brought him one step closer to his goal of helping others.

“Every time I lace up my running shoes, I think of my friend and the 15,000-plus kids diagnosed with cancer each year,” he added. “Rain or shine, in the darkest hours or through fatigue, I keep running for them. They are my unwavering inspiration.”