Fuller House star Andrea Barber—who's played fan-favorite Kimmy Gibbler since the series first incarnation, Full House, premiered in 1987—opens up about her mental health struggles and reveals why running has ultimately proved itself to be the best medicine to combat depression and anxiety.

When I crossed the finish line of my first full marathon, I cried. I cried not because of the pain, not because of everything I had lost. I cried with the realization of everything I had gained.

Running changed my life.

I have suffered from anxiety for most of my life. I experience depression seasonally; one of the worst episodes was during the divorce of my 10-year marriage.

I am no stranger to the depths of depression. I know what it's like to feel like you are in a deep hole and can't crawl out. I know what it's like to feel like you will never feel joy again. I know what it's like to feel utterly alone, even when you are surrounded by people. I know how depression affects one’s life and the lives of those around you.

Depression is a thief. A thief of happiness. A thief of hope. A thief of a life well lived.

It was during these darkest moments—the times when I was not so much living as much as I was simply breathing and existing on autopilot—when running was the one thing that made me feel alive.

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The hours I spent running on the road—reflecting on my life, listening to the rhythmic sound of my shoes hitting the pavement, feeling the sun on my face—became of form of moving mediation. I began to discover that my life had purpose again.

There is no one single prescription for depression. I have tried and benefitted from medication, talk therapy, meditation, prayer, and self-help books. ALL of these things help. But what made the biggest difference for me? Running.

There is scientific evidence of how physical exercise affects the brain by creating endorphins, which in turn releases serotonin, a type of chemical in your brain that, essentially, raises your mood and helps you feel happier. But I feel this connection goes even deeper than science.

Running helped me find an inner strength I didn't know I possessed. It taught me to become more comfortable with things that make me uncomfortable, like pain. It taught me how to endure; how to keep moving forward no matter how much it hurt. It showed me the difference between fearing loneliness and embracing solitude. It taught me that I cannot always change my life's circumstances, but I can change myself.

My positive reaction to running came as a surprise to me, because I have never been an athletic person. NEVER. I never played sports growing up. I tried out for the women’s lacrosse team in college and quit after the first practice. Going to the gym always sounded like a punishment. So why now, in my late 30s, was I so drawn to a sport that involved running many miles for long periods of time?

I feel like I have finally found a reason to run that doesn't involve competition or weight loss or winning. I run for ME. To improve myself mentally and emotionally. And a bonus is that I improve myself physically, as well.

Running has been the single greatest thing I have done for my mental health. Therapy has always been healing by helping me discover my triggers for anxiety and depression and giving me the tools to combat them. Meditation helps me stay in the present moment and stop worrying about the future. Anti-depressants helped by making me feel less—less sad, less hopeless, less lethargic. Running, however, makes me feel MORE. More alive. More confident. Stronger. Happier. Endorphins really are a powerful, natural drug.

I crossed the finish line of my first 26.2 and cried; not for everything I had lost, but in recognition of everything I had gained. A sense of self-worth. Strength. Perspective. Self-love. Happiness.

They say you lose yourself in the things you love. Sometimes, you find yourself, too.