No. 4 Diana Nyad

She had vowed this would be her last time; that she could live the rest of her life in peace if she failed on her fifth attempt to swim from Cuba to Florida.

Of course, no one believed her.

And when she emerged from the surf on Sept. 2, having traversed one of the most intimidating 103 miles on earth without the aid of shark cages, 53 hours after she began the trek and 35 years after she first embarked on the journey, Diana Nyad's words suggested she was kidding herself, as well.

"We should never, ever give up," Nyad told reporters, " ... [and] you never are too old to chase your dreams."

At 64, Nyad shrugged off initial criticism from some marathon swimmers who claimed her use of a bodysuit and facemask, which protected her from deadly jellyfish stings, characterized her achievement as an "assisted" swim.

She apologized, according to the Wall Street Journal, for saying the same thing in 1978 about Walter Poenisch, who at 65 years old became the first to swim from Cuba to Florida, doing it with the aid of shark cages and fins and also took three short breaks aboard his boat.

Completing the swim on her fifth attempt since 1978 and fourth after turning 60, Nyad triumphed in large part because her team found a mask that protected her lips -- the only exposed body part in the past -- which were stung nine times on her prior attempt, adding partial paralysis, searing pain, chills, fever, body tremors and asthma to the ever-present sunburn and fatigue.

This time, she vomited from swallowing too much saltwater, suffered from chills and had slurred speech from a swollen tongue and lips. But her mantra of "Push Cuba back, and push Florida towards you," propelled her to her goal.

The congratulatory reactions poured in, from star athletes like Abby Wambach and Ryan Lochte, to celebs like Rosie O'Donnell and even President Obama.

"I really believe this time that this is the end of the journey," Nyad said in an interview with espnW before the final swim. "If I don't make it, and I don't even like to go there because I'm believing and picturing the shore, but let's just say something happens and I don't, I'm going to look in the mirror and say to myself, 'I have nothing more to bring. There is no more research I can do on jellyfish, no more meteorologists to consult. I brought everything there is to this party.'"

That she did.