Katie Ledecky is used to entering uncharted waters.

Like how the swimmer made history at the 2024 Paris Olympics, becoming the most decorated U.S. female Olympian of all time and the first woman to win four Olympic golds in the same event (the 800m freestyle at the past four Games).   

But a few years ago, Ledecky began a private deep dive into another new area: navigating a health challenge.

It started in 2015 at the World Aquatics Championships in Kazan, Russia. Ledecky won five gold medals and set three world records, but it wasn’t all celebrations. As the athlete recalled in her memoir Just Add Water: My Swimming Life, she began feeling “extremely hot and lightheaded” at a team dinner following her final race. Chalking it up to being exhausted from her meets, she didn’t worry too much about it.

Ledecky returned to the U.S. to resume training for the 2016 Olympics in Rio de Janeiro. But again, she felt like something was off.

“It was…weird,” the 27-year-old wrote. “I was swimming okay. But I was super inconsistent. I would have a couple of good practices, and then I would have a day or two when I had absolutely no energy. Some days I couldn’t walk around without dizziness. I remember wrapping practice and struggling to get back to the locker room. Every swimmer has peaks and valleys in training, but to be so strung out? My desire to work hard was there. I just had no juice. I kept wondering, Am I sick. And if so, with what?”

Ledecky noted it was her then-coach Bruce Gemmell who suggested she consult a specialist at Johns Hopkins in her home state of Maryland. She ended up being diagnosed with postural orthostatic tachycardia syndrome (POTS), which according to NewYork-Presbyterian’s Health Matters, "is a condition in which people experience a fast heart rate, lightheadedness, fatigue or other symptoms when they go from sitting or lying down to standing.”

As Ledecky explained in her book, “Because I have POTS, I pool blood in the vessels below my heart when I stand. My body then releases extra norepinephrine or epinephrine, which adds additional stressors on my heart, making it beat faster. Which, in turn, bring on dizziness, fainting and exhaustion.”

As a result of the condition, the 14-time Olympic medalist made changes to her diet.  

“The good news was that I could treat my POTS nutritionally,” she added. “I needed to up my sodium intake and increase my hydration. Studies also show that reclined aerobic exercise, such as swimming and strengthening your core can provide relief. Which is kind of funny. What are the odds that the prescriptive exercise for my particular disease would be…more swimming?”

And while Ledecky expressed how “relieved” she was to finally have answers, she decided not to publicly share her diagnosis right away.

“I didn’t want something quote/unquote ‘wrong’ with me to become the narrative around Rio or Team USA,” she wrote. “I wasn’t eager to become a distraction or to be distracted myself. I simply wanted to treat my condition as best I could and get back to going hard in the pool. Gradually, following doctor’s orders, I started feeling better.”

Now, Ledecky—who noted she has a “solid handle on my POTS these days”—is ready to talk about her journey.

“It feels good,” she told SELF in an interview published in June. “It’s not like I was ever hiding it; it just never felt like it was something I needed to share. I’ve had it under control completely. I really just had to add salt to my diet and wear compression gear. Whenever I get sick and when I go to hot environments, I need to be especially careful to stay on top of my salt and hydration.”

Pooling her knowledge from her personal experience, the champion also revealed her advice for others living with POTS.  

“The biggest thing is to trust the health professionals you’re working with,” she told the outlet. “I did that and was able to figure out what helped me pretty quickly. I understand that for some people, it’s a longer process. But it’s important to stay patient and work with the people around you and make sure you have good people watching out for you, encouraging you. For instance, my mom is always reminding me to stay on my salt and hydration.”

And whether it comes to her health, sport or everyday life, her family and her coaches are her biggest supporters.

“I had the incredible luck of being mentored by a series of devoted and wise coaches willing to lift me up without making swimming my sole raison d'être,” she wrote in her memoir. “My family did the same. I was never pressured to perform by anyone but myself. Of the many twists of fate that lead to greatness, this support system was the one for which I’m most grateful.”

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