About 10 years ago, Diana Nyad (she/her) became the first person to swim from Cuba to Florida unassisted, a goal she had set for herself at just 9-years-old. “I stood one day on Lauderdale Beach and asked my mom where Cuba was,” she says. “She pointed out to the horizon and told me it was right there. Havana was so close that a champion swimmer like me could actually swim there. That image lodged in my soul and, when I became a marathon swimmer in the ‘70s doing those other long swims from Italy to Argentina, it was Cuba that was always The One.” Year after year, she tried and the strenuous swim again and again, all while breaking records along the way. And at age 64, Diana made her childhood dream come true.

So, in honor of National Sports Day, we talked with the extreme endurance athlete and absolute fitness icon about her historic journey, how swimming has changed her life, and her advice for those who feel like it’s way too late to go for their lifelong dream. (News flash: it’s not!)

You and your story are truly inspiring. What was that journey even like, especially trying it more than once?
I tried it at age 28, where my team and I went 42 hours in very rough seas. We were blown so far off course that we knew in the end it was not our day. I trained another year to give it another go, but visas and impossible winds pushed our team in 1979 to instead swim from Bimini in the Bahamas to Jupiter, FL. By the next year, I was getting television broadcast offers, so I actually went to work for ABC Network’s Wide World of Sports and left my Cuba dream behind.

Thirty years later, with a thrilling career under my belt and a restlessness of no longer being a doer, the Cuba Swim beckoned me once again. At age 60, how could I dare to go back to an epic challenge that I failed at even in my prime? Well, I refused to believe 28 was my prime. While it’s true I hadn’t swum a stroke in those 30 years, I had stayed in exemplary shape. The Cuba journey was not another marathon swim in my mind. This was the challenge that was going to force me to touch every ounce of potential—mentally and physically—of my being.

In 2010, the intense training began. It was a grueling year of long, long swims (up to 24 hours at a time) and hard work of organizing our 41-person team into Havana, in terms of special visas. But it was the weather that was our biggest problem. And, sure enough, we trained and waited and could never get both the wind direction and the axis of the Gulf Stream current on our side. We trained another full year and made two attempts in 2011. The first was sabotaged by an allergic reaction I had to a pain medicine administered. The next attempt was the near-death experience (no hyperbole) from swimming into a huge swarm of potentially fatal box jellyfish. The doctors on board will tell you I was lucky to live through that!

2012 became the summer of my fourth attempt, and those 51 hours of effort came to an end with a sudden tropical storm that had eight-10 foot waves. This brings us to 2013. It was 110.86 miles, 52 hours, and 54 minutes later that I stumbled up onto Smathers Beach in Key West, a lifelong dream fulfilled.

You’ve become such a preeminent woman in sports history because of this accomplishment. What has been the toughest part for you?
We sports fans watch the best of the best in their major competitions. We see them perform outrageous skills, show uncommon courage, when they’re immersed in the toughest of their competitions. Over the years, many people ask me what 53 hours of continuous swimming in the open sea is like, how hard it is. But my trainer Bonnie Stoll and I, and our team, and other extreme endurance athletes know that the real tough stuff is the training. The ardent, unwavering, and intelligent preparation for anything we care about both builds our character and sets us up for the best chance at victory.

How has swimming changed your life personally?
To feel the joy of movement, to swell with pride at doing something with the strength and the agility and the endurance of your own body, is central to feeling most alive for me. Growing up with the ocean as my playground, and then pursuing the value of a superior level of fitness every day, it’s been that physical power and confidence that’s served as the platform for all the other endeavors in my life. When I feel fit, my memory, my deepest thinking, my awe of the planet, and my perspective on life all operate from a better place. My mind is both at ease and stimulated with hope and plans when I finish a long swim. To my dying day, I will be moving.

Speaking of movement, can you tell us about your nonprofit EverWalk?
It was Bonnie and I’s answer to inspiring others to feel what we felt out on that ocean, the power and the beauty of literally traveling across the curvature of the earth on our own steam. I would have loved to have taken thousands of people out to swim in the ocean with me, but that was clearly impractical. But, many of us can walk.

We started with what we called Epics. We first went from Boston up to Cape Elizabeth, Maine. And from White Rock, Canada, down to Seattle. We’ve now led walks in every corner of the U.S., from the mesas of Santa Fe to the fall foliage of the Hudson River Valley. From a naturalist teaching you about animals and trees you find on your walks, to tips on training and injuries and gear, we are looking to take our country from the most sedentary on the planet to a nation of walkers.

And lastly, do you have any advice for those who feel like it’s too late in life to achieve their dream?
As far as anybody leaving dreams behind, it’s never too late. Dreams are also never too big to chase. I just turned 74, but let’s get real—how much time is left for me? I simply don’t want any day to go by without my grasping it with every fiber of my best being. I’ve always wanted to write for children. Maybe I’ll be a failure at it. But how will I ever know if I sit back intimidated and don’t put my whole self into it?

I say take a step in any direction. Don’t sit and wait. Imagine you start a PhD program then quickly learn that the courses are not moving you. You don’t continue, but because you were bold enough to start the program, you’ve met a fellow student who is doing something that really fires you up. Now, you’re on a new road that’s much more exciting than the last one! Don’t let anybody else dictate to you your choices, your limitations, your doubts. Don’t be afraid to fail. Be bold. This is your life—your one wild and precious life.