For more than three hours Tuesday night, Diana Nyad firmly and forcefully defended herself against skeptics who had floated theories that the long-distance swimmer cheated during her epic 110-mile crossing of the Florida Straits.
In a Skype video conference with a small but vocal cadre of doubters, Nyad tried to sink the speculation. She swatted away at one of the most persistent accusations: that she stayed afloat in shark- and jellyfish-infested waters by clutching to small vessels.
"Never did I grab hold of a boat. Never did I exit the water to sit on the edge of a boat," Nyad told NBC News.
Nyad insisted that she completed her 53-hour journey from Cuba to Florida honestly, with no tricks or gimmicks, as many of her critics have alleged on social media networks and online forums.
"I did this swim with my own body and my own mind, fair and square, squeaky clean," she told NBC News.
She also told the dozen doubters on the Skype call that she reserved the right to lay ground rules for all future marathon swims across the Florida Straits without a shark cage.
Nyad detailed her "Florida Straits Rules": All those who attempt the crossing may not use flippers or a shark cage, may not leave the water, may not hold on to the boat, may not hold on to the kayak, and may not be supported by another human being.
And yet she made some crucial allowances. Nyad would permit others to use a protective full-body suit and mask to shield against poisonous jellyfish. It's those innovations that raised eyebrows among swimming purists, who alleged that the defensive gear ran counter to the traditions of the sport.
"It is the only way. The swim requires it," Nyad said, according to the Associated Press. "I don't mean to fly in the face of your rules, but for my own life's safety, a literal life-and-death measure, that's the way we did it."
Nyad said she never once left the rough waters or gave her support team the OK to give her assistance beyond feeding her through a tube and aiding her with her thick jellyfish suit.
Andrew Innerarity / Reuters
U.S. long-distance swimmer Diana Nyad , 64, walks to dry sand, completing her swim from Cuba as she arrives in Key West, Florida, in this September 2 photo.
"I swam. We made it, our team, from the rocks of Cuba to the beach of Florida, in squeaky-clean, ethical fashion," she said, according to the AP.
Nyad has been dogged by skeptical curiosity about how she managed to make such excellent time. At some points, she more than doubled her average speed of 1.5 mph.
But her navigator John Bartlett told NBC News that the publicly-available logs will explain that she was pushed toward Key West by favorable currents.
"The current was running as fast as 3.5 knots, which is close to 4 miles per hour," he said.
At times during the three-and-a-half-hour Skype call, Nyad showed flashes of irritation and annoyance, saying: "We've been assaulted from every direction" by allegations of cheating or dishonesty.
After the call wrapped up, Evan Morrison, the co-founder of the online Marathon Swimmers Forum, said Nyad and her team tackled most of the key issues that raised suspicion among members of the forum.
He told the AP that he was satisfied by Nyad's vow that all observations and notes taken by Bartlett, as well as two official observers of the mammoth feat, will be made available for public review.
"I wouldn't expect to discover anything untoward, but I think it will help us understand a lot better what happened and give us a fuller picture of the achievement," Morrison said. "That's just part of the process. This was a great first step."
The Associated Press contributed to this report.
First published September 11 2013, 7:00 PM