Advisory Council Coordinator Paul Chetirkin sits at a computer in his Monterey Bay Sanctuary office with a 30-pound pack full of sand on his back.

“I’ve been wearing it full-time for the past month,” he says. “But I’m overcompensating. I’m hoping my pack will only be 20 or 25 pounds for the race.”

It’s the obsessive cross-training a guy with a day job needs to prepare for the Primal Quest, an expedition adventure race that’s been called the “ultimate test of human endurance, selfless teamwork, and relentless determination.”

This Sunday, June 25, Chetirkin will set out from Moab, Utah with three teammates, a map and a compass to cover a grueling 500-mile course in 10 days or less. To finish the race, international co-ed teams of four will have to run, trek, bike, kayak, canyoneer, boulder, riverboard, swim, ride horses through and just survive some of the most unforgiving territory in the nation.

No joke. In 2004, a racer was killed when his team chose an aggressive route down a rocky gully and his team dislodged a big rock that killed him.

But in the danger lies the beauty of the event. The teams creatively navigate the landscape, improvising and calculating as they go. Primal Quest CEO Rich Brazeau of Santa Cruz is a veteran of both Raid Gauloises—adventure racing’s defining event—and the US spin-off, the Eco-Challenge. He created Primal Quest with the sole purpose of significantly intensifying an already very extreme experience.

For most, just finishing will be reward enough. Of the 95 teams chosen to compete, only 12 or so have a realistic shot at winning the $250,000 prize purse. Like Chetirkin’s team, most of the competitors are really well-trained weekend warriors who just hope to make it to the finish line under 10 days.

“It’s kind of a strange sport. There’s this upper tier: 10 percent of the racers are at this expert level and are fully sponsored and they essentially race full-time, that’s what they do. They have the best gear and are in the best shape,” Chetirkin says. “But a majority are like us—people with day jobs.”

Chetirkin’s team consists of two veterans, Travis Vaughan and Marci Hansen, and an adventure race virgin, James Martin. (“He’s in for quite a treat,” Chetirkin says with a cruel laugh.) His teammates all work for Nautilus up in Vancouver, Wash., which explains why the exercise equipment giant is the team’s primary sponsor.

Since the rest of his team is in the Northwest, Chetirkin primarily trains alone. To prepare he’s spent the last four months trekking and biking the Old Coast Road in Big Sur and paddling Elkhorn Slough.

“I load up my backpack, climb on my bike and head out and back on Old Coast Road. Then using my car as a transition area, I replenish, reload my backpack and head back out on foot. I can do it in about 11 hours,” he says. “It’s only 42 miles, but it’s steep up and down. It’s pure pain. You’re either using climbing muscles or trying not to fall down.

“I also kayak Elkhorn Slough. Out and back it’s 13 or 14 miles,” he says. “Then I usually hop on my bike right after that and do a couple hours ride just to get used to being wet and pedaling with my muscles cramped from sitting in the kayak.”

If that training regimen sounds extreme, you’re not grasping how gnarly the Primal Quest race really is. It covers seven states, starting in Utah and hitting Arizona, New Mexico, Colorado, and possibly even Idaho and Wyoming.

“Initially they said it was those seven states, but there’s really no way of knowing where we’re going until it starts,” Chetirkin says. “We don’t get the maps until the night before the race. They don’t want to give you any time to plan.”

With daytime temperatures of over 100 degrees, the athletes forgo sleep to face the back country odyssey’s near-constant dangers, including nearly six miles of climbing and descending fixed ropes on vertiginous cliffs.

As a result, the team’s ability to work with each other is as important as each individual’s fitness level and skill set.

“Marcy, Travis and I have been racing together for several years…we’ve experienced an amazing bond,” Chetirkin says. “We’ve experienced the highest highs, and the very lowest lows.”

But in addition to finishing, Chetirkin has his own motivation for competing.

“As a hardcore vegan, it is also my greatest pleasure to show the world that vegan athletes can perform as well as—no, outperform—our non-vegan counterparts on a world-class level,” he says.

To track the real-time progress of Chetirkin’s team “Nautilus-Pearl iZUMi” in the Primal Quest race, visit ecoprimalquest.com once the race begins June 25.