"I FEAR not the man who has practiced 10,000 kicks once, but I fear the man who has practiced one kick 10,000 times."

This is the legendary Bruce Lee's quote explaining the importance of training and personal growth, and he pointed out that the real results can be achieved only with time, persistence, and tireless efforts.

But what about the athletes that practiced 10,000 kicks 10,000 times? They are the real giants that reached the top with their persistence and tireless work and became the best versions of themselves. That's how they became the best in the world or even the best of all times. 

They invested in themselves and charged it maximally - with money, trophies, and legacy. 

Michael Jordan is among them, who acted like a tyrant to his teammates, but just because he demanded as much from them as he did from himself. He became aware of his flaw and started working on himself. He trained his strength early in the morning, before the team training.

The late Kobe Bryant was almost a perfect copy of Jordan, equally obsessed with training and personal growth.

Roger Federer, the Swiss training grandmaster, thinks that everything crucial on the path to success is planned out since the junior days. 

Michael Schumacher, LeBron James, Wayne Gretzky, Floyd Mayweather, Michael Phelps, Lance Armstrong, and Cristiano Ronaldo had also reached the top thanks to their superhuman efforts. 

Some athletes from Croatia and neighboring countries have found themselves among the world's greatest athletes thanks to their special regime of training. These are their stories, which made them legends.

Novak Djokovic

In the last couple of years, people talked a lot about Novak Djokovic's diet, and he owes his incredible success to his crazy work on himself. His regime doesn't differ from the regimes of other players, except for the additional work. 

Everything starts with stretching and warming up, and he recommends 10 to 20 series of classic exercises of your choice. Relaxing of the muscles is extremely important, and he has massages, but he recommends foam rollers if massage isn't available.

His day cannot go by without yoga, which he practices right after waking up, after every training, and often before going to bed.

Finally, Djokovic used the so-called egg pod, a pressurized egg worth 100,000 dollars where altitude and pressure changes increase the oxygen in the blood and destroy lactic acid and other similar consequences of physical effort.

"I wanted to be the world's no.1 since I was seven years old. I still want it today the same as I wanted it before I actually happened," Djokovic explained his incredible competitiveness which led him to the top.

The world's no.1 had big falls in his career, and he especially worked on this mental strength. When he was under the weather, he spent a lot of time on the phone talking to Bryant. He came to the point that when everyone in the stadium had cheered for Federer, he would imagine that spectators were yelling: "Novak, Novak." Of course, he won.

Drazen Petrovic

One of the reasons for the mythical status behind Drazen Petrovic is his total fanaticism in training, both technical and conditional. 

"I've had respect for talent until I was 16. After that, I inclined to go along with hard work," is one of his famous quotes, which refers well to the quote that there is five percent of talent and 95 percent of hard work. 

When he started playing basketball, his nickname was Kamenko (Rocky) because of his terrible shot. And today, he is remembered as one of the most deadly shooters in history. He was especially working on his shooting skills when he was in the military, and practice made it perfect.

He used to shoot 900 times a day and made sprints in between to be as tired as possible in every next series. He had been training his butt off, but with a good reason - he wanted his training to be more difficult than the game, which he would then play with ease and pleasure. 

He loved conditioning training, and he didn't care about strength until he came to the NBA league, when he realized it was necessary for him to survive. Danny Ainge, his teammate from Portland at the time, said that Drazen used to kill time between the two practices by pedaling on a stationary bike. 

Mirko Filipovic

Mirko Filipovic's deadliest martial arts weapon was his left high kick. That's where the famous catchphrase came from: "Right leg - hospital, left leg - grave." The making of the famous kick started in an old garage, only a wall away from a pigsty. This is where Mirko would kick an improvised punching bag made out of a tarp and filled with sawdust and sand.

During his career, Cro Cop alternately combined martial arts and strength workout. One day he would have martial arts training, and the next day he would work on his strength. He would do martial arts training three times a week in the evening, and on the same days, he would do an easier workout in the morning. He would do strength workout two times a week and rested for two days. 

"With martial arts training three times a week you can cover all your needs and progress more, it's a greater pleasure than working your butt off every day because your body and your mind need to rest," Mirko used to say.

He used to point out that diet and rest, along with training, are essential factors of every successful athlete. When it comes to nutrition, he advised small meals throughout the day and eating lots of fruits. He also pointed out that "it's much more dangerous to train too much than to train too little" and that "you can do your best with the training and resting, but all bets are off if the diet isn't good."

He retired after suffering a stroke, but Mirko still tirelessly trains today. "That's my biggest addiction, and it will be like that as long as I live," he said for Index. 

Zlatan Ibrahimovic

Details about Zlatko Ibrahimovic's workout and diet aren't known that well, but the Swedish player certainly takes care of his training and diet.

The best evidence is the fact that he, as a 35-year-old in Manchester United suffered one of the most severe injuries in sports, cruciate ligament rupture, and he returned to the pitch seven months later, although the recovery was estimated at nine months. Then he joined MLS to everyone's delight. 

"Morphology, the quality of bones and muscles, everything is so good. He's one of the greatest football players I've ever encountered, he's in incredible condition," said his doctor Freddie Fu after the operation. 

Ibrahimovic has always been dedicated to training and diet, but he became more aware of its importance with time. For example, in Ajax, he didn't pay that much attention to his diet, and in 2014, during his stay in PSG, he asked the club to change the chefs. The club fulfilled his wish and brought two new chefs. Also, as he grew older, he was paying more attention to a quality warm-up before training, which he considered to be very boring before. 

It's known that Ibrahimovic always has nutritionists, doctors, and physiotherapists by his side. Besides, he couldn't have remained on the top level if he hadn't been dedicated to his body.

Ivica and Janica Kostelic

Thanks to their constant training, Ivica and Janica Kostelic have written a movie story by becoming World Cup and Olympic winners while training under the watchful eye of their father, Ante. The popular father nicknamed Gips (meaning plaster) had been taking his children to mountains ever since they were little, where they often stayed overnight in tents due to the lack of money. In those conditions, Ivica and Janica pushed the boundaries of their abilities, and later began their conquest of the greatest titles.

"There's a lot of training. We arrive at eight in the morning, start skiing around nine, and finish around 12. Then we rest for an hour, and then ski again until three or four, depending on cableway operating hours," Janica was telling about her teenage period.

Gips knew that certain abilities should develop precisely at a particular age. That's why he was borrowing money so his children could work on their coordination, explosive power, and agility on time.

Two years ago, in his life story for Index, he explained the phenomenon of a champion family, which started from sleeping in the woods and reached the world's top. The Americans and Swiss have learned from the Kostelics; no one understood how they accomplished all of it. 

Besides, who would ever, except Gips Kostelic, a handball coach in Borovo Naselje, think of finding a little hill in the middle of flat Slavonia and make a ski slope?

When asked whether he felt the unimaginable tempo of training and numerous operations as torture, Ivica told us:

"To be honest, I think it's like that in every area of life that requires top performance. To accomplish something great, many things have to coincide. We managed to function in a world with two main things - money and snow. And we didn't have either. Besides, there are other obstacles, with the system being the biggest. Systems are well-established; they have money, snow, resources, people, infrastructure. We had beaten the system, and that's why people in the world recognize us and ask us how that is possible."

Reaching the top, however, isn't the only thing fascinating about Ivica and Janica. Returning to skiing after ligament injuries is equally fascinating. Although it was estimated that Janica should have been recovering for a minimum of nine months, Gips secretly allowed Janica to step on her skies only 52 days after the operation, just so she could feel the snow.

Then she made a great comeback that you don't often see - ten months after surgery, Janica won in her first race.

"One should go back eight years in the past, to see how we trained and what we did, because it takes a long time to achieve that technique. Some might say hard work, but I wouldn't agree. Hard work isn't as important as persistence," said Gips after the return.

Ivica explained that he and Janica would have never succeeded if they hadn't trained together. 

"Janica and I would've never existed if we hadn't trained together. I had a chance to train with an athlete who was out of space; there aren't people like that in skiing nowadays, and she had a chance to train with a man her whole life. She did everything I did; she trained equally hard. That was dad's trick - he knew that women are biologically more endurable and should train equally or even more than men. Gips once told that children aged from 12 to 14 years could do absolutely everything, that's the period when they are endurable the most. Last weekend in St. Moritz, the American Ski Federation President asked Gips to hold a lecture about the development and training methods that they could implement themselves. Dad has organized a lecture in our apartment. I believe that our entire career bases itself on the training that we did at that age; that's where we gained an advantage that is difficult to compensate for later," said Ivica for Index.