Gapin, 33, is a computer engineer by day and an athlete by night. She has ran and finished seven marathons and has completed a staggering 20 races.
But perhaps her latest accolade is her most impressive, and memorable, yet - as she has become the first transgender woman to appear on the cover of the prestigious fitness magazine.
Gapin said of her debut: "Being a transgender woman on the cover of a magazine dedicated to women shows I’m being seen for who I am.
"It’s a feeling of acceptance, inclusivity, and being welcomed."
When she's not running, Gapin is a computer engineer and founder of MyTransHealth, which helps transgender people access healthcare.
She said that running had helped her overcome the "mental and emotional struggles" of transitioning.
She hopes her cover appearance will help increase trans visibility and acceptance of the community.
"For me, to be on the cover of a women's magazine is kind of a sense of validation that other people are seeing transgender women as women," she added.
Gapin is just one of many diverse women who have been featured on the cover of Women's Running magazine over the past year.
Meanwhile in December 2015, the magazine featured Kiley Lyall, from Chicago, on their front cover.
Lyall, 24, has autism and mild cerebral palsy. She featured on the cover after completing her second half marathon.
[H/T Mail Online]