When Gretchen Schoenstein’s body began to turn on her, she turned to running to regain her sense of agency. And despite doctor’s orders, she is set to run her 100th half-marathon this Sunday, one of 3,500 racing the Napa-to-Sonoma Half Marathon.

Schoenstein’s journey to this milestone marathon started back in 2006, when she was diagnosed with Sarcoidosis, an autoimmune disease characterized by inflammation in the lungs. Having previously been diagnosed with the thyroid disorder Hashimoto’s and other autoimmune diseases, doctors told her it would be best if she didn’t run anymore.

“I lived a very cautious life for three years,” she said. “I was very much in that space for a while, like ‘I can't do anything more,’ ‘I'll just live a smaller, cautious life.’ And now at this point, what I've realized is I think that the amount that I've pushed myself is, in a way, just the right amount.”

Three years after her Sarcoidosis diagnosis, she left her longtime job and lost her boyfriend of 10 years at the same time. The double whammy was jarring, and sparked Schoenstein’s desire to reclaim some semblance of control over her body.

Against her doctor’s orders, Schoenstein signed up for a 13.1-mile San Francisco half-marathon in 2010, a decision that ultimately transformed the direction of her life.

“I thought it would be good to have something to aim for, something to work towards,” the Sonoma native said. “I ran one and it felt amazing. I was able to cross the finish line, and there was a sense of euphoria, possibility and healing that happened.”

Rejuvenated by her success, Schoenstein ran four more half-marathons within the year. Her friends challenged her to double her previous total the next year. She ended 2011 with 11 half-marathons under her belt, bolstering her sense of progress.

But her ailments reared their ugly heads after each race. She was bogged down with a recovery period for the inflammation in her joints and lungs.

“I kept having flare-ups and I would have to take care of myself.” Schoenstein said. “When everybody would be celebrating after a race, I’d be back in a hotel or back at home.”

The autoimmune diseases caused pain in her knees and ankles, and the impact on her lungs proved painful and pronounced.

“In 2011 I found a pair of shoes, a company called Newton running shoes out of Colorado. They have a particular technology in the sole of the shoe that helped absorb the pounding on my joints while I was running,” she said. “So I started running in Newtons and it made all the difference in the world.”

Following the switch in running shoes, her recovery time after races was cut down as her joints felt more supported; now she only has to manage the normal recovery in her muscles and lungs. These newfound soles allowed Schoenstein to continue on her marathon of marathons. After reaching 50, people started asking about when she’d hit 100.

It was also around this time that Schoenstein wanted to run for something bigger than herself. She first ran on behalf of cancer charities to help raise awareness and money. She then shifted to a cause closer to her heart, running for Operation Shooting Star, an advocacy organization focused on autoimmune diseases.

“It fell in a place called Operation Shooting Star and its founder, Audrey, has MS and we got to talking,” she said. “And she and I have partnered together over the years to raise money for research and for awareness.”

For the past three years, Schoenstein ran on behalf of Operating Shooting Star, serving as an ambassador to raise awareness and funds that will benefit autoimmune disease research. It was then she made the pledge to reach 100 marathons in a 10-year span starting from her first marathon in 2010.

Even after running all of these marathons and the years under her belt, her doctors continued to urge her to stop running.

“I kept trying to run, and oftentimes against doctor’s orders. I had a flare-up in 2018 and had a couple doctors sit at the end of my bed and say I wasn’t running number 75, which was three weeks later. I just smiled and knew that they were wrong, and I did run. I know what my body is capable of and when I can push it and when I cannot,” she said.

In this year’s San Francisco half-marathon, she spent the entire race alongside a first-time runner and veteran who saw Schoenstein’s “Wear Blue: Run to Remember” sweater. The sweater was from a run started in Washington to honor Gold Star military families, who have lost a loved one in the service. The man had graduated from West Point with the founder’s husband who was killed overseas, and recognized the sweater and introduced himself to Schoenstein.

“So I ended up running an entire race with another runner.” Schoenstein said. “That may not be a big deal, but in 93 races, I'd never run with another runner, the entire 13 miles. So here I am, 93 races in, and I'm having a brand new experience. That is why I run, because every race is different and continues to be different.”

When the COVID-19 pandemic hit, her momentum fell flat in the quarantine. Being immunocompromised, she lived with a heightened level of fear and stopped running for four months. Then, on New Year’s Eve, couldn’t resist the urge. She started slow, with 1 mile a day, and made herself a promise to run a half-marathon on her own accord, not for an organized race.

“I ran 13.1 miles all over random little streets in Sonoma as everybody else was getting ready for New Year's Eve. It was really emotional because I didn't know if I could do it and it didn't matter that there wasn't a finish line. It didn't matter that there wasn't a medal. The most important part is I made my own finish line for being able to say at the end of that year, before it turned Jan. 1, I still was able to get one more 13.1 mile,” she said.

Inspired to continue her journey to 100, she then planned to run 11 half-marathons across five months, a lofty total even by her own frenetic standards. She managed to do five of them within the month of October, including three in one weekend. Yet still, Schoenstein insists that she isn’t an elite runner.

“I hope that I'm more relatable to people. I didn’t run in college. I don't want to spend tens of thousands of dollars on a nutritionist or a trainer. I don't win medals. I'm not that person, I'm just out here trying to see what's possible,” she said.

From the San Francisco half-marathon in 2010 to the Napa-to-Sonoma event this Sunday, she’s been driven by sheer will to reach the 100th milestone.

“The great news is no matter what happens in life, no matter what comes my way, no one can take those 100 (half-marathons) away. No one can take 50 halfs, no one can take one single half away. I've run all those. I have the medals, I've crossed every single one of those finish lines.”