National Geographic News
U.S. long-distance swimmer Diana Nyad.

Skeptics argue that U.S. long-distance swimmer Diana Nyad broke the rules in her record-breaking swim from Cuba to Florida when she donned a suit to ward off jelly fish stings.

Photograph by Alex Gallardo, Reuters

Suzanne Sataline

for National Geographic

Published September 13, 2013

Better training and greater ambition have prodded athletes around the world to attempt longer, more daring open-water swims than Matthew Webb ever imagined when he conquered the English Channel in 1875.

But lately, such victories have come at a painful price: crippling injuries caused by the sting of proliferating sea jellies. (See a photo gallery of jellyfish.)

In recent years, swimmers who navigate a Long Island Sound crossing each August have emerged in Bridgeport, Connecticut, with painful, itchy welts from plate-sized lion's mane jellies that bob at the surface.

One man who swam across Catalina Channel in Southern California last year said he repeatedly endured the electric zap of tiny jellies as their tentacles wrapped around his goggles.

Life or Death

While some jellies are harmless, others can be lethal. Though tiny, the venomous Irukandji jellyfish can cause severe cramps, vomiting, and spikes in blood pressure. The box jellyfish is also called the sea wasp for good reason. Australian swimmer Chloe McCardel was hospitalized for days in June after several box jellies wrapped around her limbs, seared her back, and floated into her mouth, scuttling her attempt to cross the Florida Straits. Pulled onto the boat by her support crew, she said her legs felt paralyzed.

Diana Nyad knows what that's like. She endured a near-fatal reaction to box jelly stings during her Cuba-to-Florida attempt last year. For her successful attempt this year, the 64-year-old donned a specially made silicone mask and stinger suit and allowed crew members to seal the seams with duct tape as she floated alongside her boat at night.

In a conference call Tuesday with more than a dozen marathon swimmers as well as reporters, Nyad said the paralyzing reaction she experienced last year left her with no choice this time.

"All of us know what pain is,'' she told the swimmers. "But this animal is different. With this swim it is the only way. I don't mean to fly in the face of your rules, but as far as I'm concerned, for my own safety, a literal life-and-death measure, this is the way we did it."

Not a First?

Yet several of the sport's most elite members wonder if that's missing the point. They say that wearing a long-sleeved suit and having any physical contact with other people (other than inadvertent brushes) are improper forms of assistance that conflict with the widely accepted rules of open-water marathon swimming.

These swimmers insist that Nyad's swim was "aided," so it's no different from Susie Maroney's 1997 crossing of the Florida Straits in a shark cage—and therefore is not a first.

"She used equipment beyond what's traditionally accepted, and it gave her aid; it aided her swim. The equipment wasn't self-sufficient. She needed people to help her get it on and off,'' said David Barra, a marathon swimmer from High Falls, New York, who has crossed the English and Catalina channels.

Breaking the Rules?

The rules of open-water marathon swimming date back to its founding father, Matthew Webb, a sea captain who was the first man to swim the English Channel in 1875. "I think one of the beauties of the sport is that the rules are largely unchanged since [then],'' said Evan Morrison, a founder of, a website with more than 700 members.

Today, the two English Channel swimming associations—and scores of other official swimming bodies—ban any action or device that aids a swimmer's buoyancy, speed, heat retention, or endurance. People swim the English Channel in neoprene wetsuits all the time, but their swims aren't recognized as official crossings.

One of the main no-nos is human contact, because that can aid buoyancy or allow the swimmer to rest. By letting her crew help her don and seal the stinger suit, Nyad got a chance to rest, Morrison said.

The point of channel swimming is to get from shore to shore. "You don't get to rest,'' said Morrison, a San Francisco resident. "If you feel the need to use devices to make exceptions to the rules, why do you feel the need to do that? The answer is unpleasant: to make it easier. If you're trying to make it easier, you're missing the point. The point is it's hard."

"If Diana is claiming a record that has meaning to her sport, she needs to play by the rules of that sport,'' Morrison said.

Swimming is a sport of tradition—one that has seen few advances. There are exceptions: Athletes wearing Lycra swimsuits are faster than the earliest endurance athletes who had only soggy wool garments. On-boat technology such as GPS has improved course selections and finish times. Swimmers who compete in the Rottnest Channel Swim in Australia can wear rash guards to ward off sunburn.

As the warming of the world's oceans fuels the proliferation of jellyfish, perhaps the widespread use of special suits to ward off stings won't be far off. But the sport's purists remain loath to allow innovations beyond the cap, grease, and goggles used by generations, saying it will destroy the integrity of the sport.

If Nyad is right that the crew-applied stinger suit was the only way to freestyle the Cuba-to-Keys passage, Barra said, then perhaps such crossings shouldn't be tackled. "If the only way to climb this mountain is to take down the top thousand feet, it's not the same,'' he said. "Maybe some mountains shouldn't be climbed."

Mark Harewood
Mark Harewood

Think its a bit harsh , to say she broke the rules , by wearing a wetsuit ! I dive often and have seen people wear short sleeve wetsuits in warmer pacific diving areas and they have come across jellyfish and been stung on the bare  arms and it isnt comfortable , although in most cases not deadly . I think if she was swimming a 100 metres in a swimming pool , with a wetsuit , i would say she was breaking the rules !

Swimmer by Nature
Swimmer by Nature

Penny Palfrey, an accomplished ultra long distance swimmer and perhaps the most highly regarded ultra-swimmer by those posting on, has written about stinger suits:

"Where tropical waters are infested with jellyfish with life threatening venom, I do not believe it’s cheating to wear a protective suit that does not artificially enhance a swimmers ability. On the contrary I believe it’s being responsible. In fact they do actually make a swimmer slower and cause problems such as extra drag and chafing."

Ms Palrey's entire piece was published by the SBCSA in their March 2013 Newsletter:

Zsuzsanna Toth
Zsuzsanna Toth

I am not familiar with the  rules of Marathon Swims ( I just run them )  so I can't judge who is right who is wrong...but this story  makes me sad .

We all receive help at any long distance physical activity ( gels water , massage on the leg if you have a cramp , you can even have a pacer , so why not helping putting on a swim suite ?)

What I see is a great achievement and a vey sensible life saving decision for the challenge . 

I just wonder if all those skeptics have ever proved anything similar in their life  ?

Roiikka-Ta P Globetrotter
Roiikka-Ta P Globetrotter

am i missing something? where is it ever documented (proof?) that the suit was applied while she was swimming? whats to say that she didnt just put it on herself then hop in the water and make the whole swim .. ? theyre saying that there was "human contact" during her swim. at that id think i have to agree with the others in saying that it would be cruel to not allow an advance for the better good of the person just to not get stung by the jellyfishes. if the only way to climb this mountain is with climbing gear, then maybe this mountain is to be left untouched ..

Marathon Swimmer
Marathon Swimmer

I read that the large number of jellyfish in the Florida Straight were following the warm currents and that there are a lot less jellyfish found in the straight between November and May. If this is the case, the straight could be swum in cooler water to avoid the jellyfish. Yes this brings forward another challenge, but that is what this is about. The straight can be swum without a assistance.

Swimmer by Nature
Swimmer by Nature

You wrote: "... English Channel swimming associations ... ban any action or device that aids a swimmer's buoyancy, speed, heat retention, or endurance".  That is fundamentally not true.  English Channel rules allow drafting alongside the escort boat throughout the swim.  They ban slipstreaming behind the boat, but allow drafting along side the boat.  This violates the maxim "getting to the shore under your own power".   Not all EC swimmers take advantage of drafting, but some do.  In fact the most recent record breaker for the EC, Trent Grimsey, drafted at the instruction of his boat pilot who said it was necessary if wanted to have a chance at breaking the speed record.  This has been documented online by someone who was on Trent's boat.  Apparently, all recent EC record breakers have drafted off the side of the boat as well.

Roger Bird
Roger Bird

New Rule:  The Cuba to Florida marathon swim and any other swim where there are Box Jellies must be swum with a wet suit on.  The only exceptions will be those skeptopaths who are so stupid as to fail to realize that no human being would be so stupid as to swim 100 miles through Box Jelly invested waters.

Swimmer by Nature
Swimmer by Nature

@Mark Harewood... in diver lingo (I dive too) Nyad wore a 'rash guard' or 'dive skin', not a (neoprene) wetsuit.  

She wore it (her stinger suit) because humans cannot acclimatize to jellyfish stings, particularly those with life-threatening venom.  As noted ultra swimmer Penny Palfrey wrote (see my comment below) wearing a stinger suit when swimming amongst life threatening jellyfish 'is being responsible'.

Neoprene suits are verboten among the ranks of traditional long distance swimmers  because everyone can physiologically acclimatize to cold water to some degree.  Just how deep a given swimmer is able to acclimatize can be limited by their genes for metabolism and body shape.  Yes there are physiological limits to acclimatization.

It just happens to be the case that the English Channel is warm enough that it can be swum without thermal protection provided the swimmer acclimatized beforehand -- a process that generally takes many months of dedication.  And yet the English Channel is cold enough that it 'cannot' be swum without acclimatization. 

If it had been some other channel that had become famous, one that was beyond anyone's acclimatization, neoprene might well be allowed.  So in essence, the ban on neoprene is not based on principle, it is just a historical fact of chance.  

Swimmer by Nature
Swimmer by Nature

The stinger suit and mask do not aid in buoyancy, speed, heat retention, nor endurance.  Quite the opposite according to Evan Morrison and others: the stinger suit and mask make the swim harder. 

The objection that is being raised is the help Nyad had in putting it on and taking it off.   One has to wonder whether teh few minutes of help really does out weigh the hours of hindrance. 

@Marathon Swimmerwhat would make your proposal more of an accomplishment? 

Here is a recent interview with Evan Morrision where he states that the swim is made more difficult by the stinger suit and mask.


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