When Westporter Jenny McGuinness crossed the finish line of the TransRockies Run—a grueling 60-mile-and-8,000-foot-elevation-three-day ultramarathon in the Colorado Rockies—this past August, she wasn’t just completing a race, she was proving something far more powerful: that gratitude and grit can coexist with chronic illness and uncertainty.
Jenny’s relationship with endurance goes back decades. A lifelong runner, she competed in track and cross-country at Colgate University, a Division I school where she also met her husband, Luke, a teammate and kindred spirit. For them, challenge and motion were the norm. Their two sons, ages 12 and 17, have grown up surrounded by this culture, where signing up for a mountain race is simply what you do. Jenny and Luke moved to Westport from New York City in 2013, drawn by the schools, community feel, and proximity to both ocean and forest. She kept up her avid running here: favorite routes include the Saugatuck Trail in Weston and Redding, and a coastal road loop from Compo through Southport.
For 20 years, Jenny ran injury-free. Then, life threw her a curveball.
In 2019, after completing an Ironman and transitioning into triathlons to preserve joint longevity, she began to experience inexplicable joint pain. A tick-borne illness triggered an autoimmune response, and soon after, she was diagnosed with rheumatoid arthritis (RA). As a physical therapist, she knew exactly what the diagnosis meant—and how devastating and physically limiting it had the potential to be.
“I spent a year pretty bummed out,” she recalls. “I had always defined myself by my physicality. Letting go of that identity felt like grieving a part of me.”
Worse, the uncertainty was maddening for her Type-A personality, which was used to scheduling her life down to the second. “Every day with RA brought a different version of my body,” she said. “But I made peace with that. I realized: there’s a grey area. That’s okay. I can still be me. I just have to adjust.”
And adjust she did. Slowly. Patiently. Layer by layer, challenge by challenge.
Then came the second blow: a heart arrhythmia that was first diagnosed in 2022, but with worsening and more worrisome symptoms that progressed in the spring of 2024. . “I was like, ‘Really, Universe? Now this?!’” she recalls. Jenny was told to scale back intensity and distance, which was especially concerning for the high-altitude TransRockies race she had just signed up for. The race, she says, had long been on her “hardcore bucket list,” and when she learned 2025 would be its final run, she decided to register despite her RA and arrhythmia diagnosis. It was her way of proving she could still take on a challenge of this scale. The TransRockies race involves steep mountain ascents, unpredictable weather, trail terrain unlike anything she’d ever run, and camping alone each night between stages. “I chose to do it solo,” she says. “I knew with the altitude and the challenges of off-trail running it was gonna get ugly at times, and I needed to go to that dark place by myself.”
Jenny had to amp up her training, from a typical week of running about 15–20 miles with cycling and swimming mixed in to four weekly runs—two on roads and two on trails with a weighted pack of up to 22 pounds—plus twice-weekly strength sessions.
Even with her training limitations, her cardiologist, Dr. Linda Casale of Fairfield—who happened to be a fellow triathlete and trusted teammate—helped her find a path forward. “She’s a straight shooter and didn’t say no,” Jenny says. “She said, ‘let’s work within the boundaries. Let’s figure out how to do it safely.’ That was so enabling for me.”
Training began in earnest nearly a year before. She started with the smallest possible steps: bodyweight movements, what she calls “grandma-level” strength work, and short jogs with a backpack. She adapted each session based on what her body would allow. “Taking action was empowering,” she says. “I wasn’t going to sit back and let these diagnoses define me.”
Another critical layer in her preparation—one she believes made a huge difference—was heat training. Jenny added stair climber workouts followed immediately by sauna sessions twice a week. “There’s a ton of research now showing how effective heat training is for altitude adaptation,” she says. “It helps expand plasma volume, which really pays off at elevation.” She followed a targeted approach: 15–20 minutes in the sauna, ideally three times a week. She started nearly two months before the race, and always after a high-intensity effort. “I was consistent about it,” she says. “And I think that was massive in getting my body ready for the altitude.”
To prepare, she and three local friends—fellow endurance junkies and everyday sources of inspiration—tackled the Grand Canyon’s Rim-to-Rim route in May. It was 22 miles, 8,000 feet of climbing, and took 14 hours to complete. It was her test run, and it worked. “If I could do that, I could do this,” she recalls thinking.
On August 4th of this year, she set out on day one of her three-day run. After each of the full days of four- to six- hours of climbing, descending, sweating and problem solving, she would set up camp in the wilderness, try to get some sleep, and do it all again the next day.
The lowest point came on the second day, as she climbed 3,500 feet to Hope Pass, 12,500 feet above sea level. The altitude sickness hit hard. “That whole day was such a place of darkness,” she says. “But I kept thinking: one step, then the next. Don’t think an hour ahead. Just keep it small, and just do.”
Jenny’s approach—part creative, part clinical—became her superpower. “It was a weird merger of my PT brain and my creative brain. I had to pivot every day. It kept things interesting, and forced me to listen closely to my body.”
Her family—Luke, and sons Gray and Hank—were waiting at the end to cheer her on, an hour’s drive from the course. “Seeing them from far away made me start sobbing,” she says. “I felt like Pac-Man chasing the dots to reach them.”
By the final finish line, she felt not broken, but whole.
“I’ve never said ‘I’m proud of this’ before,” Jenny admits. “But this? I’m proud. Just being at the start line was an accomplishment for me, with everything I had to overcome to even get there. And now, I know I can keep going.”
Gratitude has become a daily mantra. “Any day I can move my body through space, I’m grateful,” she says. “Perseverance is a word I have on my wall—but gratitude is right there next to it.”
As for what’s next?
She grins. “There’s a race in South Africa called Comrades—it’s 52 miles, all uphill or all downhill. I’m planning to do it in 2027.” She’ll have her husband and two local Westport friends with her in tow. She said it herself: if she can do this, she can do anything. And knowing her, do it she will.
“I had always defined myself by my physicality. Letting go of that identity felt like grieving a part of me.”