JUREK ISN'T ALONE IN feeling that way. Here's an obscure sport finally getting some attention, but for a reason that makes many competitors break out in the mental version of athlete's foot: the preening of two of its stars. Racers joke about Karnazes leaving a mirror at the midway aid stations. When he was described on 60 Minutes in March as possibly having run farther than anyone else alive, computer listserv junkies jumped all over the claim as bogus, citing Kouros and others. While other runners have certainly gone farther, the question of whether running so far nonstop is a "first" opens up a morass of other questions, like what constitutes "nonstop" and how fast you have to be going to still call it "running." When Karnazes appeared on the Late Show with David Letterman that same month, one scribbler on the Ultra listserv vented, "Dean Karnazes is just another self-promoting huckster."

It was the 60 Minutes segment that really hyped the rivalry, focusing as it did on the two Badwater front-runners as they competed in 2004. Before the race, Karnazes told Lesley Stahl, "Coming in second is the worst thing you could ever do, because no one said, 'You had a great finish at Badwater.' They just say, 'You lost to Pam.'"

Still, Karnazes maintains, being targeted by Reed for one-upmanship is a surreal experience. "We've raced a dozen times together, and she's won once," he says. "I'm a little bummed she's playing up the Badwater thing. She wants to get revenge. It's not like I'm the only one who beat her." (Reed came in fourth.) But the envy makes sense. Karno has what Reed yearns for: a lucrative running life.

Cash helps, because the road to glycogen-powered enlightenment isn't cheap. Like most elite ultrarunners, Pam Reed loses money. Between event fees, travel, and gear, she spent close to $25,000 last year. A fraction of that was covered by two speaking fees and a few free products—shoes from a Tucson running shop, some Ensure, and all the Red Bull she can drink. (As a "friend of Red Bull," Reed does get some expense money, but she still sits a rank below their top athletes. "I want to be that, their top level," she says.) Although the family is comfortable—her husband, Jim, is a tax accountant and they spend summers in posh Jackson Hole, Wyoming—Reed's global competitions strain their finances. What Reed would like is, yes, a little validation, but mostly some cold, hard cash.

Hence the stunts. "Dean and I are oddly similar," says Reed. "We've done off-the-wall things."

Karnazes seeks out his very own categories. Only three men ran in the 2002 South Pole Marathon, the other two in snowshoes. Although Dean finished second, he made it known that he won the "running division," becoming the first person to complete a polar marathon in sneakers. Last year, he traversed the Western States course in winter, a supposed first. In 2003, he set out to run 300 miles nonstop on a mountainous course, but quit at mile 226. Now he's considering retracing the steps of legendary Greek messenger Pheidippides, who carried dispatches from Athens to Sparta in the Battle of Marathon in 490 b.c. In his book, Karno compares himself to Pheidippides; for good measure, he plans to run wearing full armor.

Karnazes knows that some of his colleagues rag him, and responds by pointing out that his runs raise hundreds of thousands of dollars for leukemia and organ donation and increase the sport's visibility. "In my defense," he says of his book, "it's a memoir. It's not a definitive statement on ultrarunning. I never claimed to be an authority on ultrarunning or necessarily a good ultrarunner.

"It's either jealousy or whining," he says of his detractors. "I wish they'd come to the bookstores and see how inspired people are about it."

Their real problem, he feels, is with the very idea of the chummy, clannish sport undergoing a makeover. Many runners want to keep the races small and obscure, an attitude that chafes him. "I find it comical that people are saying you're giving away the Garden of Eden," Karnazes says. "I'm like, Shit, I can see that about a fishing hole or a secret surfing break, but there's a lot of open road in this country."

And some ultrarunners agree with him. "This sport needs to be a little more mainstream, as opposed to so extreme and underground and hidden," says Shannon Farar-Griefer, 44, who in 2001 became the first woman to run a "double Badwater"—for a total of 292 miles (with naps). A Los Angeles resident who looks like a cross between Goldie Hawn and Olympic marathoner Paula Radcliffe, Farar-Griefer appeared in a Slim Fast commercial and is writing a memoir.

"I love it that Pam and Dean are doing this," she says. "Three years ago people would have whooshed me away. Now I can jump on their thing. I just sent Energizer my portfolio. It's time for a new bunny."