A marathon runner with alopecia was called a 'sick, ugly man.' Now, she’s highlighting the beauty of her hair loss journey.

Lindsay Walter has run 52 marathons, but doesn't typically buy pictures of herself crossing the finish line after a race. When it came to the London Marathon on April 23, however, she finally saw a photo of herself that she was proud of — so much so that she decided to purchase it and post it on social media. When someone commented to say that she looked like a "sick, ugly man," she was overcome with shame.

"It hit me so hard because when I was a kid, the one thing that was the biggest trigger and ultimate gut punch was when someone would call me a boy," the 32-year-old, who struggles with hair loss on her scalp and body because of an autoimmune condition called alopecia universalis, tells Yahoo Life. "Because I didn't have hair people would [say], 'Oh, you're a boy.' And so for me, that's the one thing that just hurts me the most."

The condition, which impacts fewer than 200,000 people in the U.S., is something that Walter has dealt with since she was diagnosed at age 2. For much of that time, her way of coping was hiding what she felt made her different.

She explains that she's worn a wig since she was young and tried to "escape" her condition by lying to people about her hair. She even used double-sided tape to secure the wig as she played basketball throughout high school and college, justifying the discomfort for what she felt was a more acceptable appearance.

"For the longest time, I honestly felt like I was ugly," she says, noting that she preferred her talent to make her stand out, rather than her bald head.

When she found running, however, that began to change.

Walter ran her first marathon as a college senior in Duluth, Minn. after being a spectator for years. "I just remember showing up to the marathon just very undertrained, very underprepared. But it was just the most incredible thing," she says. "With the runners, everyone looked so different that having alopecia, like I looked different and I felt different, but like a part of the group at the same time."

Her quick decision to take up marathon running after crossing that first finish line was inspired by that feeling.

"I just started running marathons all over the country. I loved the training, I loved being in a new city where no one knew me, no one knew about alopecia. And it just, I mean, kind of escaping my alopecia for a little bit," she explains. "I wore a wig for several marathons, again, doing the double sided tape and the headband, just like I had done with basketball. But the more I started running, the more I was gaining confidence in myself."

The confidence that she felt in her abilities as a runner carried over to other areas of her life, including how she felt about the way alopecia impacted her appearance. She began talking to close friends about her experience with hair loss and even running errands with just a hat on her bald head. During a long run in preparation for a marathon in 2016, she finally bared it all.

"I took [the wig] off and I remember just holding it in my hand and it was a dripping wet with sweat and it smelled disgusting. For the first time in over 20 years, I didn't think it was beautiful," she says. "I got home and I hung up my wig. And I sat there looking at myself in the mirror and just you know, like really noticing my facial features."

Walter was 26 years old at the time and just coming to terms with what she would look and feel like without a wig. She's only grown more sure of herself and less concerned about her appearance in the time since. The London Marathon, which she says was a bucket list item, was a celebration of that.

"I never buy race photos, and I bought that photo because I loved it. And I look so strong, and I was just so proud of my effort and training in London," she says of the shot she posted to her Twitter and Instagram accounts. The first comment she noticed was someone who said she looked like a man. "It just like brought me back to my childhood."

She deleted the photo from Twitter in response. "Immediately I took the photo down and I just had this moment of feeling like so self-conscious. And just like oh my gosh, I do look like a boy. Everyone's gonna think that," she says.

A short run allowed her to think more deeply about her reaction.

"I just was thinking back to just all the marathons I've run, all I've done like in the alopecia community as an advocate," she recalls from that jog where she decided, "I'm not letting negativity win, I'm standing up for myself."

She did just that by reposting the photo with a message asserting how much she loved the picture. Thousands of others agreed.

"Just standing up in such a graceful and positive way, is just, that's just my personality and who I am. So just reposting that, I just felt so proud of myself," Walter says. "The response to it was mind-blowing and overwhelming. I was not expecting any of that. But like 99.9% of people were so kind and encouraging. And it just made me feel like everything in my life that had been negative with alopecia is just blown away by how kind everyone was."

Walter hopes to be a bright light in other peoples's journeys with alopecia through her work with the community and by continuing to show up authentically online.

"As a kid, I just always felt like no one truly understood because I didn't know anyone who had alopecia. Had I known someone or seen someone's alopecia photo go viral, that would have helped me so much," she says. "With firsthand experience I can say [to those kids], 'I know what you're going through. Losing your hair sucks and it's really hard and you're gonna have bad days. But here's also how you can turn it into a positive.'"

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