Next tonight, diana nyad is taking on her critics. We all cheered her epic swim from cuba to florida at the age of 64. And then the skeptics began questioning whether she could have gone so fast 110... See More
Next tonight, diana nyad is taking on her critics. We all cheered her epic swim from cuba to florida at the age of 64. And then the skeptics began questioning whether she could have gone so fast 110 miles in 53 hours. Abc's gio benitez now. He talked to diana nyad and he did the math. Reporter: Diana is passionately taking on her critics. We did this squeaky clean. Reporter: How did she cut a full day from her swim time? An unusually powerful current. They say it would be so rare it would be almost magical. That's ridiculous. Yes, did I finally after five times get some luck with the current? It's not magical. Reporter: So we decided to reach out to an independent oceanographer. He did the math. She hit the current lotto. She happened to hit it at the perfect time. Reporter: He says this current comes around only a few times a year with speeds of three and six mile per hour. Add that to her average swimming speed of 1.5 mile per hour. That could have easily at times powered her up to 5.5 mile per hour, enough to have carried her the last 50 miles in 22 hours. Then there is the question of the food. Did she really go without eating for seven hours as her blog seemed to suggest? It's just erroneous. Never would we go more than an hour without taking in sustenance. Reporter: Remember, there were 44 people on her team. We talked to two of them who told us nyad's swim was the real deal. I heard you on the call say that you want the whole world to see this data. You want it available to everyone. 100 percent. We want to live in 100 percent transparency. Reporter: Her passion seems to have taped the critic but today they say I believe she swam from shore to shore as she says she did. We want to bring you up to
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