I first heard of Martin Strel on the documentary film festival circuit in early 2009. A film called Big River Man — about a Slovenian dude who played classical guitar for the Pope and swam the length of the world’s longest rivers — was making waves at Sundance and Edinburgh. I immediately felt called to see it.

Later that year, I found myself at a mystery screening in Berlin. One of those nights where you’re either blessed with an early showing of There Will Be Blood, or cursed with The Love Guru. On this particularly hot summer day, in a moment of pure kismet, the enthralling story of Martin Strel flickered onto the screen.

The film portrayed a man who loved life, beer, food, and wine. Like, really, really loved wine. But also accomplished feats of physical exertion that you only read about in obscure medical journals or comic books.

The Martin Strel I saw on screen that day wasn’t some über-fit Adonis you’d expect to see at the Olympics. He was a portly and fatherly guy who relished eating horse meat burgers and pounding pitchers of beer mid-swim. Here was a person who was able to push his limits in ways that seemed impossible, who also happened to be an average looking dad with a pot belly and a tall-boy in one hand.

Strel doesn’t swim for valor and accolades. He swims to highlight the natural world and our disservice to it. He has a mission to bring cultures together. He travels the world and swims for us to question our materialism. He swims for an earth that’s in trouble. He swims for us.

We talked with Strel about what it’s like being a marathon swimmer, how you avoid being eaten by sharks, crocodiles, and piranhas, and how anyone can keep moving for a dozen or more hours every day and live.

How old are you?

Sixty-two years old.

How many rivers have you swum?

I have swum the Danube, Mississippi, Paraná, Yangtze, and Amazon.

Your father was a driving force behind your love of the water. But not necessarily through positive means. Tell us about your first memories of swimming?

Where I grew up there was drinking and drinking and drinking. Everyone is drinker. Some of them heavy drinker. Some of them just drinker. [My father] came home with three big dogs. “Where is Martin?” “He’s here.”

Oh, he’s trying to catch me! Where to go? I jump in the water. Middle of the water. And he didn’t catch me. Middle of the water, that was the safest place for me. I was pretty good swimmer already. And dogs jump on me. But dogs didn’t bite me. My father was trying to beat me with this chain and sticks. He didn’t find me many times because that was my water. Water became a part of my life — a very good friend for my safety.

You learned that you could survive in the water. Where did you go from there?

I swam more and more — up and down. Believe me, I never seen anybody swim up and down so long, so many … not minutes, hours. I swam hours. And people didn’t believe. They said, “This guy’s crazy. What’s going on … something must be wrong with him.”

There’s no one else in the world who swims like you do. Why do you swim?

When I was kid the water was clean, so many crabs and fish. Clean water everywhere. Beautiful nature. But then they started building new roads. And they destroyed all these creeks and rivers. All the crabs died. All the fish died. Even plants. Then I decided to swim for peace, friendship, and clean waters, especially.

Tell me a little bit about the physical and mental challenges that go into undertaking marathon swims.

Swimming the greatest rivers on the planet is not so simple. You have to be very clear in your head. In the beginning to the end. And after then, too. Before you jump in the water, you have to know how many states, how many languages, what is dangerous, what is good for you, what is not good for you, what is the quality of the water, what animals, what about scientists, chemists. And then, if you can swim, what to eat, what to drink, how many calories per day, how many calories you lose to temperature if it’s very cold. You have to know everything before you jump in the water.

It’s much easier if you’re mentally very clear. You’re in pain. My complete body’s in pain. It was hard to swim. Many times I said, “It’s enough today. I’m going home. I simply can’t make this.” But then, after a good shower, a good dinner, a massage, okay, I’m gonna try again tomorrow. Maybe I can make one day more. Then one day, two, three, four, one week, and another week. And then I was done. Finally.

How do you get through the pain?

Meditation. I can say that I can hypnotize myself. It’s not true. But it’s very close. It’s something that helps me a lot. I’m not afraid of swimming around the world or swimming with dangerous animals. But you have to know how to do this. If you are a good guy, if you’re clear in your mind, if you’re not aggressive, you can swim with most dangerous animals that are on the planet and they won’t attack you.

We’re not just talking bucking up to finish one more lap here. We’re talking about focusing enough to go 20 or 30 more miles. If it’s not hypnotization, per se, what would you qualify your mental state when you’re swimming through the pain?

In the year 2000, I didn’t know. It was pain. Lots of pain swimming hours and hours in the oceans, lakes, rivers. It was very hard. And then on the Danube, it happened. You have fears and you don’t know how to move or what to do, but you have to swim. You have to finish this. I was in the water and I found the way. When I feel pain my concentration gets very, very deep. And then I don’t feel pain anymore. Can somebody explain it to me how was this? I don’t know. But it works … for me. Then I swam the Mississippi, it was much easier for me. And then Amazon. Even easier. When my body’s in trouble when I swim, my concentration gets very, very deep. Like meditation. And then I’m gone.

Mind over matter?

Now if somebody said to me, “Would you like going swimming around the planet? Is this possible?” It is possible. Sure it is possible. Everyone is ready physically. This is no big deal. But mentally it’s a big difference. That’s the reason why, for example, Michael Phelps is just a little better than other swimmers. Maybe half-inch or one-inch sometimes. But it’s enough. Why is Michael Phelps different? Because I think that psychologically he’s a very, very strong guy.

How are you different than other swimmers?

I’m different because I am clear here [points to his head] at the beginning to the end. I’m very clear now with this experience. And how I prepare, every trip, from day to day, week to week, it’s very important. I prepare…

So when you’re having doubt, when you’re having fear and think this is really dangerous or maybe you could die, how do you push that fear out of your head?

You have to know how to swim. Some people say to me, “Martin, we see a shark!” I ask, “Which way?” “Over there!” Okay. You meet fish a lot. They eat nonstop and they are very friendly. Then I swim. And shark is far, far, far away. He’s very afraid being close to me. Simple. It’s not good to be aggressive. You can survive these animals. Like swimming with crocodiles. Crocodiles are not aggressive. But you have to know how to swim with them.

Do you prefer the company of animals more than people?

I am like half-animal, half-human. I go to walk with so many different animals because I love this place very much. And I love all the animals.

Tell me what the worst moments have been with swimming?

Down Mississippi on Cape Girardeau, Missouri. I passed this big buoy. Lightning touched this buoy. And it was like big explosion. Pushed me out of the water. Like a big hammer touched me. I was unconscious immediately. But I didn’t die. I was okay. I stopped for a couple of minutes, like lunchtime, middle of the water. And then, ‘go, Martin!’ And then in the Amazon was terrible moment attacked by piranhas.

How do you escape a piranha attack?

You feel fire. You can’t see anything because it’s murky, muddy waters. So piranhas are big, like two feet long. Small ones, too. But they eat so fast. They opened my back. We had buckets of blood [on our boat]. They love blood. They target the blood immediately. And they were gone. You can play with piranhas. Piranha is very nice fish. You can swim with piranhas. They love calm water.

What are people’s reactions to your swimming?

Most people simply don’t understand how you can swim like 12 or more hours per day. I swim. I have to. I have to make 30, 40, 50 miles or more per day. Every day. Not just for today. Day by day, week, another week, three, four weeks. People say, ‘this guy’s crazy!’ But I’m not crazy. I’m maybe a little different. In my mind everything is very, very clear.

It feels like you’re self taught.

I need a little more time. I don’t swim four or five hours a day. I swim 12. Even more sometimes. Sometimes it’s 17 hours to find an exit. If you love something and you know where the finish is, then it’s much easier. The first step is important. When you make first step, the second is easier.

How did you learn the discipline that carries over into your swimming?

You have to be precise every day. I swim three times a day — at night, a little in the morning (take a nap) and late in the afternoon. This is the best food for your brain, taking a little nap.

I’m up early in the morning. I prepare breakfast. I swim then a little nap. And this is the beginning of every day. Good beginning. Good for my health, for my body. Even though I’m a little overweight, it doesn’t matter. Then you have to work. Then I swim again. Doing cross-country skiing. Hiking. Trying to find companies wanting interviews, whatever. Then, by the end of the day, there must be a little relax. I have to be in the bed every night before midnight.

What do you do when people tell you that something is ‘impossible’?

If somebody said to me, “This is impossible!” I think, “it is for you, maybe. But not for me.” I usually don’t say anything. I’m quiet. I need a little more time, thinking about that. Then I can say that climbing Mount Everest was impossible. But now it’s possible. Everything is possible, really. I believe in this and not just cheering the impossible.

What are some of the amazing accomplishments that you have performed that still stand out to you?

When I finished the Danube I decided to break record for swimming 300 miles nonstop. This is very hard swim. 340 miles in 84 hours and 10 minutes. What was, for me, almost impossible, but now it’s possible. I swam across the Red Sea from Africa to Europe. Where the salt concentration’s very high. I made 100 miles in 55 hours and 50 minutes. Again, extremely, extremely hard swim. Not about the distance. But about the salt. The salt destroyed my mouth, my tongue, my eyes. And now I prefer swimming in fresh water.

How long was the Amazon swim and how many days did it take you to do it?

Amazon swim was 66 days long. And I went 3,274 miles.

In your biggest year of swimming, how many miles did you swim?

So 2007, I swam 5,000 miles, including the Amazon.

On average, how many miles do you swim a day?

On the Amazon, 53 to 54 miles per day. On the Mississippi swim with the dams it was average swim of 36 miles per day.

What Guinness Book of World Records do you hold?

I have five Guinness world records. First was the Danube. Then Mississippi. Then Yangtze. Then Amazon. And nonstop swimming for 84 hours and 10 minutes. I didn’t sleep more than 105 hours.

Is swimming an escape for you now?

No. Now it’s like a part of my life. My cardio. It’s like my food for every day. When I go from the bath straight into the pool, I feel different. I am different there. If I don’t do it, I really, really miss the water. Water is big relax for me. Good food for me. Good exercise for me. You can swim at the beginning of your life when you’re one-year-old. And you can swim to the end of your life.

Can you talk about how water makes you feel and affects your mind?

You have to listen. This is nature. You can’t fight with nature because nature is stronger. We would like to fight. Going to the Everest, swimming this, doing this. But you have to respect nature to be very close to the nature. This first.

Do you feel like you’ve had to compromise to live this life and this dream?

I’m not Mother Theresa. I’m not so religious. My religion is to understand people and to help people. What we need. People say, “This guy’s millionaire! This guy’s billionaire!” But what you can buy with one million dollars? I have house. I have car. I have good food. Same water we drink. Same ocean. The same river. The same lakes. What’s the different? He has money in the bank. I don’t have money in the bank because I don’t need to have money in the bank. The simple life is the best life. Go in the middle of the jungle you will understand what relationships these people have. How they love one another. They don’t have money. They don’t have cars. But very good life. Very. They help one another with whatever is wrong immediately. No selfish people. This is like big, big family. We need something like that today.

What are you searching for in your life? What’s your dream?

We have to save this planet for future generations. Can you imagine a thousand years from now what people would say about us? Not good. Pollution everywhere is so high. No drinking water anymore. Technology is getting better and better, sure. We believe in this. But is not good to destroy this planet.

If someone says “I feel old,” what would you say to that person?

You’re never old. Even 70, 80, 90. That’s just here in your mind. You have to care about what you eat. Mentally have to be very busy every day. Food is very important. And so is working with the right people everyday.

Who is Martin Strel?

I am Martin Strel, professional guitar player, and, accidentally, I became professional marathon swimmer.