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Well, she's doing it the hard way.

Endurance swimmer Diana Nyad stroked through the Florida Straits early Monday, trying to accomplish at 61 years old what she failed to do at 28: swim more than 100 miles from Havana to Key West.

If she makes it to the Florida Keys after an estimated 60-hour swim, Nyad would become the first person to traverse the strait without the aid of a shark cage, relying instead on technology and divers to fend off the finned predators.

Tanned and freckled from long hours training in the open seas of the Caribbean, she expressed confidence before starting off just before sunset Sunday. She said the still air and shimmering water flat as a plate were perfect conditions for her attempt to make a 103-mile (166-kilometer) swim.

"The adrenaline's flowing now," Nyad said at a jetty in western Havana as she looked at the water. "... This is what I dreamed of: a silver platter."

She gave a heartfelt cheek-kiss to the commodore of the Hemingway Marina in Havana, who helped arrange logistics of the trip, changed into a black swimsuit and blue swim cap and showed off the goggles she planned to wear: light blue during the night for better dark vision and smoky charcoal tinted to protect her eyes from the blinding daytime sun.

After an assistant greased her shoulders and armpits to prevent chafing in the salty water, Nyad played "Reveille" on a bugle, thanked several dozen well-wishers who came to see her, then jumped feet first into the sea.

Nyad said it has been a lifelong dream and she hopes her feat, if successful, will inspire people to live vigorously during their golden years.

"Thirty-three years ago I stood on a beach close by here and looked out at a giant sea. ... Now I'm almost 62 years old and I'm standing here at the prime of my life," she said.

"I think this is my day."

Nyad first had a go at this crossing back in 1978, when she swam inside a steel shark cage for about 42 hours before sea currents hammering her off course put an end to that attempt.

The following year she set a world record for open-water swimming without a shark cage, charting 102.5 miles (165 kilometers) from the Bahamas to Florida, then retired from competitive endurance swimming.

Still, she said the aborted Cuba attempt stuck with her all these years, and upon turning 60, she started thinking about a comeback.

"What if I went back and tried to chase that elusive dream of Cuba?" she said. "And I started training and I found it was in my heart and it was in my body. ... It seems almost like a dream to me, but now it's real."

In preparation she made 8- to 15-hour swims over the last two years off the Caribbean island of St. Martin.

Australian swimmer Susie Maroney successfully swam the shark-filled waters from Cuba through the Straits and to the Keys in 1997, though she used a cage.

Nyad's team is deploying an electronic boom to surround her with a current that is imperceptible to humans but is strong enough to keep most sharks at bay. Whitetip sharks are not deterred by the field, so divers will be standing by to gently discourage any of those who get curious -- without harming them.

For the record to be considered valid, Nyad will have to make the swim without a wetsuit. Her crew will navigate, monitor her health and provide nourishment. But she is not allowed to touch the boat, nor can her helpers hold her, until she emerges fully onto dry land.

Five support vessels carried 45 navigators, nutritionists, doctors, shark wranglers and a film crew that has been documenting her story.

She plans to stop every 45 minutes for 20-second hydration breaks -- water, juice, sports drinks. Every 90 minutes she'll rest for 2 minutes and nibble on bread or a spoonful of peanut butter.

By day two she'll begin drinking heated water and hot chocolate to ward off hypothermia, a threat after so many hours at sea even with water temperatures expected to be 86 to 88 degrees Fahrenheit (30 to 31 degrees Celsius).

Nyad embarked on a northwest course aiming to arrive at a point in the Keys a little east of due north, compensating for sea currents.

She called the attempt a "symbolic moment" for increasing understanding between the United States and Cuba, two nations torn by five decades of animosity and mistrust.

"I'm under no delusion that my swim is going to make any new political ramifications," Nyad added. "But it is a human moment between the two countries."

Based on reporting by the Associated Press.

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