When black women walk, things change.

This statement was running through my mind as I watched the movie Harriet opening weekend.

Starring Cynthia Erivo, Harriet follows the legendary life of Harriet Tubman. In case your high school history teacher failed you, Tubman was an American abolitionist and activist who became the most famous “conductor” on the Underground Railroad.

Born into slavery in Maryland, she was originally named Araminta Harriet Ross and nicknamed “Minty” by her parents. Tubman escaped to freedom by fleeing to the North in 1849. She then risked her life to lead family members and other enslaved people to freedom through the Underground Railroad’s elaborate secret network of safe houses. During the Civil War, Tubman served as a spy for the Union and was the first woman to lead an armed expedition that liberated more than 700 enslaved people.

To free herself and to free others, Tubman walked hundreds of miles.

When black women walk, things change.

These words are a part of the mission statement of GirlTrek, the largest public health nonprofit for African-American women and girls in the United States. A civil rights-inspired health movement, GirlTrek encourages women to use walking as a practical first step to inspire healthy living, families, and communities.

The GirlTrek mission states, “From Harriet Tubman to the Montgomery Bus boycotters, one thing is certain; when black women walk, things change.”

GirlTrek centers much of its programming and literature on Harriet Tubman. You can even download Harriet’s Handbook for ideas of different types of walks to take.

Ironically, I almost didn’t go see Harriet because of GirlTrek. The organization tried to partner with the film to mobilize members to lead walks to the movies during opening weekend. After the partnership fell through, I felt some kind of way and thought about not going to see the film. But my mother had her heart set on seeing Harriet during our next Girls Day Out and I didn’t want to disappoint her.

So I saw the movie and I’m glad I did. Harriet isn’t perfect, but it’s an inspiring film with solid performances by Erivo, Janelle Monae and many others. If Twitter told you this was a movie full of white saviors or that it paints Tubman as a weak woman who’s pining after lost love, you heard wrong. Yes, we see her handle heartbreak, but this only humanizes her character; it does not weaken it. The movie isn’t completely historically accurate, but I didn’t go into it expecting a documentary. What I appreciate is that Harriet is not a story centered on suffering. It’s a tale of triumph with a focus on faith and flashes of feminism.

Harriet also made me even more committed to the idea that when black women walk things change.

From June 30, 2014, when I completed my first 100-mile challenge.

Every year in June I challenge myself to walk/run 100 miles. I started this challenge because of GirlTrek, which means I started this challenge because of Harriet Tubman.

I’ve written before that I never do this challenge to lose weight but to gain confidence, the confidence to go after my writing goals. If I can walk/run 100 miles in Alabama’s summer heat and in spite of a chronic medical condition I have that tells me I shouldn’t be able to, then I can do anything else I want to do, too.

GirlTrek’s mission also states, “This is not a fitness organization, this is a campaign for healing. This is not recreation. This is a lifestyle.”

I took this to heart this year and after I successfully walked 100 miles in June, I woke up on July 1 and kept walking.

In his famous essay “Walking,” 19th-century American author Henry David Thoreau writes about the virtues of immersing oneself in nature through walking. In the essay, he recalls a story about William Wordsworth: “When a traveler asked Wordsworth’s servant to show him her master’s study, she answered, ‘Here is his library, but his study is out of doors.'”

During my walks, my study is out of doors, too. My yearly walking challenge gives me the confidence to go after my writing goals, but my daily walks give me the creativity to do so. My best ideas for stories, blog posts, and even business come to me when I’m walking through my neighborhood or on my favorite trail.

But I want to do more. I don’t want my walking or my writing to be just about me.

Writing is a privilege. Walking is, too. It is a privilege to have the time, the ability, the freedom to do either.

Audre Lorde once said, “I am not free while any woman is unfree, even when her shackles are very different than my own.”

How can I use my writing and my walking to set my sisters free?

I can tell women’s stories and help them share their own. I can walk to raise money and awareness for causes I believe in. And I can encourage other women to walk, too — for health, for happiness, for healing, and for Harriet.