It’s hard to pick the most amazing thing about Tina Marchese.

Is it that she relishes participating in Spartan races, a combination obstacle course and endurance test that would leave most normal mortals begging for mercy? Is it that she’s convinced her reluctant husband (“He thinks I’m a little crazy for doing all this,” Marchese admits with a laugh) and their 7-year-old son to run the courses as well? Or is it that she started doing Spartans after she had been diagnosed with multiple sclerosis in 2016, and has no intention of letting up anytime soon?

Marchese demurs. “People tell me all the time that I am an inspiration,” she says, sitting outside a White Marsh Starbucks just weeks before taking on yet another challenging Spartan course. “But I just keep doing what I’m doing. I just keep going.”

That’s putting it mildly. At 37, the Perry Hall resident has taken part in four Spartans since her October 2016 diagnosis; she’s in training for her fifth, scheduled for Sept. 21 at Philadelphia’s Citizen’s Bank Park, where the Phillies play their home games. A finance manager for White Marsh-based Applied Technology Services, Marchese says she’s always been in good shape, running half-marathons and 10Ks; she’s been doing high intensity interval training, a regimen of cardio workouts, for years. Staying in shape has always been important to her, and that hasn’t changed.

“When I was diagnosed, I don’t think I was going to allow anything to change,”she says. “One of the first things my doctor said to me, my first neuro appointment, was ‘You are not to stop exercising.’ Now, granted, she probably didn’t like the fact that I increased my exercising. So it’s funny, every time I go to my doctor, it’s, like, ‘What race are you doing now?’?”

Multiple sclerosis, or MS, is a disease of the central nervous system that disrupts the flow of information between the brain and other parts of the body, according to the National Institutes of Health. It can be treated, but there is no known cure. Initial symptoms generally appear between ages 20 and 40; these include muscle weakness, numbing or tingling sensations, blurred or double vision and dizziness.

Her diagnosis, Marchese says, “caught me completely unaware…I had started developing a headache. There was pressure behind my eye. But I let it go — ‘There’s nothing wrong.’ Finally, my vision was going, and I was, like, ‘Now there’s something weird happening.’?”

Although the symptoms are not persistent, she says, they’re definitely there. “I’ve noticed my feet drag if I heat up, I start to feel like I’m walking through sand or concrete…The tingling and numbness is all part of the MS. The shakes, I drop things. I get tongue-tied. There are some days when I just don’t want to do anything.”

That hardly sounds like the ideal conditions for a woman pushing her endurance to the limit. The specifics of Spartan races vary, but generally include sprints, stair climbing, obstacle courses and other events. Marchese’s had to do tension bikes, mud crawls, rope climbs, even pull herself up over walls. “I always feel like there’s a lot more walls than there should be,” she says with a smile.

She’s especially prone to getting overheated, Marchese says. But that’s just another challenge. “Heat doesn’t resonate well with me, especially with my MS,” she says. “Sometimes I collapse, sometimes I don’t. One time, I came off the bike and completely collapsed. I was, like, ‘There’s no way I’m gonna finish this.’ But I did.”

Her doctor says Marchese is staring down MS in exactly the way it should be stared down. “The thing that is wonderful about her approach is that she’s not letting MS define her,” says Scott Newsome, associate professor of neurology at Johns Hopkins Hospital. “She’s doing everything that we would want our patients to do.”

That includes inspiring others, including those who take on the Spartans alongside her. “A lot of people who get that diagnosis, you would never think that she would want to take on everything that she has taken on,” says Emily Bungori, a friend for some six years who was recruited into the Spartans by Marchese. “She knows that she can physically and mentally get through it… She’s the type of person, if you tell her she can’t do it, she’s going to do it anyway.”

Adds Rick Faircloth, who met Marchese through the Spartans and will be in Philadelphia alongside her, “Some of the things she does are impressive for a healthy person. For her to be able to do that with MS is nothing short of amazing. She inspires everyone she knows.”

Marchese, who lives in Perry Hall with her husband, Robert, and their son, Masen, admits that her MS can make things difficult. But, she asks, why should that matter?

“There’s some days when I’m, like, ‘Why do I even do anything?’ When getting out of bed in the morning, I’m like a bag of lead sometimes. And I’m just, like, ‘I guess I’ll just get up and do a workout.’?”