The Detroit River was chilly on the morning of July 9, 2021, when Kara Wolter slid into the water to begin her half-mile swim.

The cold made it difficult to breathe, especially because Wolter had had several lung surgeries. But Wolter was determined to brave the biting temperature. She'd been waiting to freestyle through these choppy waves for years.

That day, Wolter was participating in the Motor City Mile Open Water Swim. It's one of more than 20 local swims, organized by the nonprofit Swim Across America, that raise money for research at cancer centers in their communities. The University of Michigan Rogel Cancer Center receives all funds raised from the Detroit event

As both an avid swimmer and a Rogel Cancer Center patient, Wolter was eager to take part in the inaugural Swim Across America Motor City Mile, in 2019. Yet a portion of her left leg had recently been amputated to ensure that her osteosarcoma, a type of bone cancer, wouldn't return or spread, and she didn't have enough time after the surgery to train for the swim. She geared up for the 2020 event, but organizers ended up nixing the in-person group swim in favor of a virtual format because of the pandemic.

All of this was tough on Wolter. She'd been swimming since a diagnosis of Osgood-Schlatter disease, which causes pain in the growth plate near the knee. At the time, the diagnosis forced her to quit running track and cross country as a teenager, but the water had always been her happy place.

"I loved it, and I learned quickly," she said. "I was never necessarily the fastest swimmer, but I was one of the most beautiful swimmers."

After Wolter's amputation in 2019, her connection with the water grew even deeper. Its low-impact nature took away her pain, and she didn't need to change much about the way she flowed around the ripples, unlike her movement on land, which required much more planning and assistive devices like a wheelchair, crutches, her prosthesis or a cane. In the water, she was free.

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"I still sometimes get very angry that I lost my leg and realize that this is for the rest of my life and that it's not just going to grow back one day," Wolter said. "But being in the water makes me forget that I'm missing my leg." 

"People are amazed that I can swim, and I'm like, 'Well, what do you mean?,'" she added. "It just turns into more upper body, you know? And I've been swimming for so long prior to my leg loss that it's instinct to me."

And swimming helps Wolter physically just as much as mentally. She credits the activity for her high scores on pulmonary function tests, despite the multiple tumors she's had her in her lungs. And Danielle Raymond, P.T., her former physical therapist, believes it's improved Wolter's ability to use her prosthesis.

"Swimming promotes improved respiratory and cardiovascular fitness, increased flexibility and strength as well as pain reduction," said Raymond, who works in the Department of Physical Medicine and Rehabilitation at Michigan Medicine. "All of those physical benefits have helped Kara to use her prosthesis more successfully."

But when indoor pools closed to reduce transmission of the coronavirus early in the pandemic, it was difficult to find places to swim, particularly over the winter. And Wolter's latest round of chemotherapy made her so tired that exercise often wasn't feasible. In February, she was so ready to be back in the water and get a break from cancer treatment that she and her boyfriend, Bill, took a trip to Key West, Florida.

"Once I got in the ocean, it was a whole different feeling of just, 'OK, I can relax. I feel at home here. I feel good here. Nothing hurts,'" Wolter said. "That's the biggest thing — there's no pain. It just feels good." (It didn't hurt that Bill proposed on that trip either.)

Since then, as vaccines became more available and the air warmed, Wolter began making lap lane reservations at the Dexter Wellness Center's pool and taking advantage of the lakes in the area. She wasn't pushing herself to train for Swim Across America, so to speak, but she regularly swam half a mile, the same distance she planned to take on in the Motor City Mile swim.

On July 9, Wolter arrived at the Belle Isle beach house, the designated meeting place for the swim, with an entourage in tow: her dad, her mom and a family friend. She ran into other friends too, including Rob Atteberry, who has competed in half-marathons, triathlons and Ironmans since his brain cancer diagnosis.

Some faces were new, like Vicki Bunke, who's swimming in 14 different Swim Across America events this year in honor of her daughter, Grace, who died of osteosarcoma at age 14. Wolter cried listening to Bunke speak, and Bunke came over and gave Wolter a hug afterward. 

And then it was Wolter's turn to serve as inspiration. A young woman came over and asked to take a picture with her, having heard Wolter speak at the 2019 event. (Wolter had parked her wheelchair at the finish line to shake hands and cheer participants on, even though she couldn't swim.)

"She ended up saying that I inspired her in 2019 to swim, and this was her first year doing it. And it was because of me," Wolter said. "That made me tear up a little bit. There were actually so many people coming over and telling me they remembered me from 2019 and they were so glad I was swimming, and that was really nice."

The race itself was challenging, especially with the river's strong currents. But Wolter's father, Klaus, swam with her as her "guardian swimmer," checking on her every few minutes to make sure she was doing OK.

When Wolter got out of the water, Rob Butcher, the president and CEO of Swim Across America, asked her if she would swim a mile in the event next year. Wolter was out of breath, which she says might have influenced her response of, "I don't think so."

But she said she'll be at the 2022 event, even if another surgery keeps her from swimming, to support everyone there — and the cancer center that she says has saved her life multiple times.

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"The nurses there are amazing, the doctors there are amazing, the janitors, the front desk people, the people in the parking structure, everyone there is just amazing," Wolter said. "It is definitely the place to go if you have a rare cancer."

"But some cancers do not have a lot of research behind them, such as osteosarcoma, because it is so rare," she added. "So it's nice to know that my cancer center and others around the country are receiving funds from Swim Across America for a better future and — maybe even one day a cure."