HAVANA (AP) — Marathon swimmer Diana Nyad stroked laboriously through the waters north of Cuba early Saturday, braving schools of jellyfish while testing the limits of human endurance on a quest to break her own 3-decade-old distance record.
Fans and well-wishers around the world were kept up to date by messages posted by Nyad's assistants on social media. In a series of dispatches sent on Twitter about 9:30 a.m. EDT (1300 GMT) Saturday, the team reported that the swimmer was about 25 miles (40 kilometers) from Cuba as of 9 a.m.
"It's been a challenging night and morning," said one tweet, which noted that Nyad had recovered from multiple Portuguese Man O' War stings, but that her "usual stroke pace, between 52 and 55 strokes per minute, has dropped to 48."
"But she is able to swim," the tweet said.
Her team earlier had reported that Nyad was stung on both arms, her side and her face. After untangling herself, she took a half hour off to tread water, rehydrate, change suits and don a new shirt before resuming in favorable sea conditions.
"'It was scary' said (chief handler and close friend Bonnie) Stoll," one tweet said. "But Diana is happy that this happened early while she is still at her strongest."
The latest tweets also noted that two doctors from the University of Miami treated Nyad with oxygen and other medications Saturday morning.
Nyad treaded water between 7 a.m. and 8 a.m. "and said she felt better, but still couldn't get enough oxygen to her muscles," another tweet said.
Nyad set out Friday evening on her second attempt in as many months to traverse the 103 miles (166 kilometers) of sea between Cuba and Florida, waving goodbye to well-wishers before jumping feet first into the still water at a Havana marina, then swimming toward the horizon.
If she succeeds, the 62-year-old Los Angeles woman would set a new record for open-water swimming without a shark cage. Nyad holds the previous record from a 102.5-mile (165-kilometer) swim from the Bahamas to Florida in 1979.
Her last attempt at the Cuba-to-Florida crossing failed Aug. 9 due to a crippling asthma attack that forced her gasping from the water after 29 hours.
Just before she set off from Hemingway Marina this time, assistants smeared grease on her shoulders to prevent chafing during the planned 60-hour journey. She pumped her fists in the air as her support team blew horns and cheered from waiting boats, and vowed to give everything she had to pursue what has been a lifelong dream.
"I know I'm going to be cold," Nyad said. "I know I'm going to run into all kinds of jellyfish and the nights are going to be long."
She acknowledged being a little more subdued than the last time she departed from this same marina.
"Not that I was ever cocky, but having been through this now and been so deeply, emotionally disappointed, I don't want to take anything for granted," Nyad said.
"It's not that I don't want to enjoy every moment and savor it, but it doesn't do any good to act like, 'Hey I've got this in the bag, this is going to be easy.'"
Before jumping in, Nyad weighed herself, tipping the scales at 146 pounds (66 kilos). She said she expected to lose about 15 pounds (seven kilos) over the course of the journey. Her schedule called for her to reach Florida early Monday morning.
Nyad hoped to take advantage of what she called a "magical window" of calm seas and favorable weather forecast to last through the weekend.
Last month after her previous attempt failed, Nyad had vowed there would be no repeat, but she joked earlier Friday that nobody should have believed her.
"Don't listen to athletes when they say it's over," she said.
She first tried to cross the Florida Straits as a 28-year-old back in 1978, when she swam inside a steel shark cage for about 42 hours before ending the attempt.
Nyad denied her problems in the last attempt had anything to do with her age, saying she could have fought through the choppy waves and "excruciating" shoulder pain. But she hadn't anticipated the 11-hour asthma attack that she blamed on a reaction to a medicine she had never used before. She said the asthma had her flailing through the water "like a dying, floundering fish."
Even with those problems, she made it about 50 miles (80 kilometers).
In the ensuing weeks she concluded that the aborted attempt was not so much a failure as a dress rehearsal, an unplanned but necessary part of a training regimen that included a bunch of shorter swims.
"The asthma took me down, but ironically enough, that 29-hour swim was like a very, very expensive training swim," said Nyad, who earlier this year estimated it took a half-million dollars to get her to the first attempt.
"I'm in better shape than before. I'm more prepared than ever," she added.
Without a cage for protection, Nyad is relying on special equipment that surrounds her with an electric current imperceptible to humans but strong enough to keep most sharks at bay. Kayakers also are paddling alongside to gently prod away any that make it through.
For the length of the crossing, Nyad will not be allowed to touch the boat if the record is to count. Nor can her team physically aid her other than to pass her food, medicine, a new swimsuit and so on.
She will try to sustain her energy by eating the likes of peanut butter sandwiches and pasta, and said she sings Beatles, Bob Dylan and Janis Joplin songs in her head to keep her mind occupied, especially during nighttime.
"I never ever — it's the cardinal rule — I never look up because it's very depressing to see the horizon with no lights, no nothing. And I never ask my trainer here in the boat what time it is or, 'Are we almost there yet?'" Nyad said. "They're going to tell me when we're about 10 hours away."
Nyad's site: www.diananyad.com