KEY WEST, Fla. — The clocks Diana Nyad uses to time her training swims show that she is slower than she used to be. That is only natural: At age 64, she acknowledges, she is no longer the “thoroughbred stallion” she was back in the day.
But the endurance athlete felt stronger than ever when she became the first person to swim 110 miles from Cuba to Florida without a shark cage.
“Now I’m more like a Clydesdale: I’m a little thicker and stronger — literally stronger, I can lift more weights,” Nyad said in a one-on-one interview Tuesday, a day after she finished her 53-hour, record-setting swim.
“I feel like I could walk through a brick wall. ... I think I’m truly dead center in the prime of my life at 64.”
Older athletes tend to find more success in endurance events than power events such as sprinting and other sports that rely on “fast-twitch” muscle fibers, which are more difficult to preserve later in life, noted Wojtek Chodzko-Zajko, a physiologist at the University of Illinois Urbana-Champaign.
But just because Nyad was swimming rather than pounding her joints against the concrete does not mean she didn’t achieve a remarkable feat, Chodzko-Zajko said.
“This ultra, super-length swimming is brutal regardless,” he said, adding that another reason older athletes are able to endure is because they often train smarter and have a mental concentration that is well honed over decades.
“She’s one of any number of people who are redefining what happens with aging,” said Dr. Michael Joyner, at Mayo Clinic.
“If you start with a high capacity, you have some reserves,” Joyner said. “You can lose some absolute power, but what you lose in power you can make up for with experience and strategy and better preparation.”
Nyad first attempted swimming from Cuba to Florida at age 29 with a shark cage. She did not try again until 2010.
She tried twice more in the past two years before beginning her fifth attempt Saturday morning with a leap off the seawall of the Hemingway Marina into the warm waters off Havana. She paused occasionally for nourishment, but never left the water until she reached the white sand beaches of the Keys.
Nyad says her age and maturity should not be discounted when measuring her success.
“It’s not so much the physical,” she said. “All of us ... we mature emotionally ... and we get stronger mentally because we have a perspective on what this life is all about,” Nyad said.
“It’s more emotional. I feel calmer, I feel that the world isn’t going to end if I don’t make it. And I’m not so ego-involved: ‘What are people going to think of me?’ ” I’m really focused on why I want to do it.”
Susie Maroney, an Australian, swam the Straits in 1997 at age 22 with a shark cage, which besides protection from the predators, has a drafting effect that pulls a swimmer along.
This June, Chloe McCardel, 28, made it 14 miles before jellyfish stings ended her bid.
Nyad admitted Tuesday that she was glad when McCardel did not make it before she had had a chance to, but she did add, to laughter from her team, that “I didn’t want her to get bitten by jellyfish or die or anything.”