The morning before I meet Karla Kent, I run five miles in a 96-degree scorch. I suffer. But with every footfall comes the needling thought of this 49-year-old woman covering that distance 27 times over. And taking on Badwater—“the most demanding and extreme running race offered anywhere on the planet”—is about more than the 135-mile expanse. The brutal course is nonstop from Death Valley to Mount Whitney, and racers contend with 13,000 feet of elevation gain, heat that can boil to 130, the innate limitations of their bodies and the darkest places inside their minds. Some call it the road to hell.

Then there’s Kent. On Monday, July 16, she toed the Badwater start line. About 40 hours later, she finished, took one day off and was back at the Bellagio by Thursday, dealing roulette on her feet from 8 p.m. until the sun rose.

We’ve never met, but I know her by her legs. The lithe, tan muscle draws stares. If these people knew what that muscle just accomplished, the staring would be more about the fact that Kent can still walk. “The worst part is going down stairs,” she says, her roots in the Czech Republic coming through in her accent. “I’m surprised how good I was feeling the next day. Maybe I should have pushed harder.”

This makes me laugh almost as hard as Kent saying she’s “average.” She’s referring to her pace in the realm of ultra, but the word just doesn’t fit someone who could run from here to Barstow, California, for Del Taco if the mood struck. Since winning Las Vegas’ Running with the Devil marathon in 2007, she has completed 18 ultra races. The moniker applies to anything over 26.2 miles, though the typical mileages are 31, 50, 62 and 100, with a handful of monsters such as Badwater. Among the 96 elite athletes invited to participate in this year’s 35th anniversary event, Kent ranked 62nd overall and 11th out of 17 women (only three were older). Not bad, especially considering her only real training runs were a 50-mile race in June and one 30-mile jog through Red Rock Canyon.

I gape at this admission. She smiles sheepishly. I gape again when she describes her transition from first-ever 5K immediately to half-marathon. Once she knew she could do that, she went straight for a marathon in her home city of Prague, almost breaking four hours without really training. She’s not boastful at all, just matter-of-fact.

“If I do the one step, I’m like, ‘What’s next?’” she says. Outside of a spinal disc issue that laid her off racing for several years, she recovers inhumanly fast. Like ultra legends Marshall Ulrich (who had his toenails removed), Pam Reed (who can run 300 miles without sleep) and Dean Karnazes (who eats large pizzas during races), she is built for the impossible.

“It was like a dream because they were all there,” Kent says of the company on the Badwater course. “When you run these big races, let’s say the New York Marathon, you know all these top runners are there, but you never see them. You never get close to them. These people are there taking pictures with you, talking with you. It’s wonderful.”

But the big names aren’t the ones she credits with getting her across the line at her first 100-miler. It was the 2010 Labor of Love in nearby Lovell Canyon. When night fell, Kent’s poor vision and massive blisters under her big toes forced her to walk. Ultrarunners typically walk up hills to combat fatigue, but this was for keeps. Fifty-five miles in, she resolved to finish no matter how many painful, frustrating hours it took.

“So I’m walking, and it’s miserable, and it’s night, and I’m questioning my sanity,” Kent says. That’s when a Californian named Jakob Herrmann appeared. Sacrificing his own race, he walked with her, sharing stories of rookie blues and assuring her that sunrise makes the world look different. They picked up another guy whose Achilles tendons were shot, and the trio stayed together to the end.

Kent’s next 100-miler went better and, with the subsequent two, taught her personal tricks. Bring extra head-lamps. Avoid solid food. Set goals from tree to tree rather than start to finish. Accept that foliage looks like people (or purple dinosaurs) when you’re exhausted. Do yoga to stay race-ready. Even if you don’t like soda in everyday life, trust in the “miraculous” powers of Coke when you’ve pushed your body beyond its breaking point.

“At that point, whatever looks good to you will probably be good because your body somehow knows better,” says Kent, whose only other race ritual is wearing a tiny gold heart around her neck. Her grandmother gave her the locket at birth, and she never takes it off. But it’s not for luck. Luck can’t touch the utter surrender experienced by the seven competitors who dropped out of this year’s Badwater. Kent points to her head. “It’s all up here. Even if you have the physical part, if you don’t have the mental part you’re not going to finish. Because after hours and hours and hours out there, I think the mental is even more important.”

Funny she should say that because her hobby seems mental in the other sense: the crazy sense. Research scientists question the cardiovascular strain, and armchair critics wonder what psychology drives such recreational punishment. Kent is simply curious about her own limits. As long as it’s not too dangerous, as long as it doesn’t “own” her, she’ll keep pushing. Her sights are set on a full Ironman before she turns 50, and she’s hoping for another shot at Badwater. There’s no prize money. Public adoration is modest. And under such extreme conditions, personal records go out the window.

“The first person and the last person get exactly the same thing: a shirt, a medal and a belt buckle,” Kent says. “You just feel good no matter what, as long as you get there.”