Deena Kastor has written the book on the power of positivity in competition and life. Now injured, she's putting her advice to good use.

Deena Kastor, the American marathon record holder (2:19:36) and 2004 Olympic bronze medalist, was after another piece of hardware this year: the six-star medal for completing the World Marathon Majors events in New York, Chicago, Boston, Tokyo, London, and Berlin. Next up was supposed to be the Berlin Marathon on September 28, but as it turns out, an accident will keep her from competing.

About two weeks ago, Kastor, 46, tripped on a dog leash during a training run near her home in Mammoth Lakes, California. An X-ray revealed a fracture. But she is practicing what she preaches in her book about positivity, Let Your Mind Run.

“My silver lining through all of this is, ‘I guess I have something to chase in 2020!’” she wrote.

Kastor recently talked with Women’s Running about how strengthening her mind and relying on positivity has led her to so much success in the sport.

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Today, I’m sitting by a lake I would typically be running around. At least I know to give myself a good view. Almost two weeks ago, very near where I sit, I tripped over a dog and her leash. I got therapy and continued to put in the final hard week of training for the Berlin Marathon. It hurt. Yesterday, I finally got an X-ray which revealed I had broken my ankle. Almost immediately, my goal of getting an @wmmajors ⭐️ ⭐️ ⭐️ ⭐️ ⭐️ ⭐️ 6-Star medal became a goal of healing. Sometimes you get so close to your goal you can taste it, and yet in this moment there is not a cell of self-pity. As I’ve practiced positivity over the years it seems readily available when I need it most. My silver lining through all of this is, “I guess I have something to chase in 2020!” To all of you planning fall races, I wish you the best in your final preparation. Most likely, I’ll be cheering with the other crazy fans on the roadside. And YOU, chasing your 6-Star medal, I’ll continue to join you in this prestigious undertaking! #6starmedal #6starmedalgoal #berlinmarathon #run #powerofpositivity #abbottwmm #runnerproblems #runnerprobs #optimism

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Women’s Running: When did you realized that the mind and positivity are so much more important than we think they are in running?

DK: I always thought that the hour you were in your running shoes is all that mattered. I didn’t even make the connection that recovery was important, and didn’t even realize the extent to which hydration, and nutrition, and sleep played a part in it. And so that to me was so fun to play with, and to see results just immediately getting an extra hour of sleep every night, making better food choices, eating more abundantly.

Showing up, knowing that I’m rested and recovered and that what I did in the last 20 hours were toward recovering from the workout before. It made me excited to see what my body can do after that. And so, every day I was kind of fired up and excited, and it was really that mind-body connection that played out so beautifully, and it ended up making me excited to see how much deeper I could go with this. Like changing my thoughts to “oh my God, there’s a hill up ahead” to “oh cool, this hill is going to make me stronger.” Just changing the little dialogue in my head, day after day, made such a huge difference to now, it’s more of my default, but I still have to work on it.

WR: How did you get better at battling negative thoughts?

DK: It was all organic because there wasn’t a lot of written work about it, so it was almost like I was experimenting with myself and shifting a thought when a hill was coming up [for example], and seeing how powerful that little shift was just because I was paying attention to what my thoughts were, instead of just accepting them. Paying attention and then changing them to benefit me more. I just kept playing on that.

[I noticed that] although I was trying to be the cheerleader, the tone [of my self-talk] was really condescending. I was like, “Okay, now I have to work on my tone,” because I would come to a hard part in workout, say that the second to last mile repeats and I would say, “Oh, come on.” But that wasn’t what I really meant. I meant like, “Yeah, let’s go! Let’s go!”

It’s really incredible that [positivity] is not just a thought. It creates a chain reaction in your body with hormones, and then the neuromuscular connection. Our thoughts are completely linked to the nervous system of our body, the adrenal system of our body, the muscular system of our body. And I think that seeing that power really excited me to continue on.

We have a great privilege as a sport to put ourselves in these stressful situations, where we feel fatigue and a little bit of fear that we may not make it to the end. Then when we put ourselves in these harder moments to be able to get through them, because they are like stressors to our lives.

WR: How does that carry over into our daily routines?

DK: Running gives us a really beautiful way to be able to toy with those harder emotions, those uglier emotions, and see how we can overcome them. [Like] being able to deal with stubbing your toe walking to the bathroom in the middle of the night, and making sure an F-bomb doesn’t fly out of my mouth. Instead, I think, “Okay, I need to pay better attention to where I’m going.”

I think that we can learn a lot through the places we put ourselves in running. And sometimes if we make it more about a life experience, it takes the pressure off of the moment. It is just a race; it is just a workout. But if we gain a strength out of our mentality and our physical bodies, then let’s play with the way to do that.

WR: How do you suggest we infuse more positivity in our lives?

DK: I love the Headspace meditation app. I did it with my daughter. I did it with our entire youth running club this summer. I think it’s fantastic to show that we can hype ourselves up and run through sprinklers, and then we can calm ourselves down and pay attention to our breath. It’s empowering to show ourselves what we’re capable of, getting up when we need to get up and calming down when we need to calm down.

One of the most powerful things I have done for my mentality is keeping a gratitude journal—just how it builds and grows and deepens and just really brings things that I’m grateful for to the forefront of my life, instead of things that I’m maybe resentful of or frustrated with. It’s releasing endorphins and good hormones in your body instead of stress and cortisol. It can be something you say into your phone while you’re waiting in traffic. It could be something you write down before you go to bed at night. The fact that you’re just giving attention to the positive things in your life is really important.

This conversation has been edited for length and clarity.