Welcome to the log-hauling, wall-scaling, mind-twisting test of endurance, where you never know what happens next.

Don’t call it a mud run, buddy run, or dirt dash. A Spartan Race is a timed obstacle course event created to be the ultimate mental and physical challenge. “It’s not a party, it’s an athletic event,” says series founder Joe DeSena. “This would be the Olympics if obstacle course racing were an Olympic sport.”

Sure, some obstacles are guaranteed to pop up at every event, like the barbed-wire crawl, the eight-foot wall, and the rope climb. But this series has roots in the Death Race, a 48-hour-plus adventure race where competitors never know what’s coming next. So don’t try to study maps of the approximately three-mile Spartan Sprint, eight-mile Super Spartan, or 12-mile Spartan Beast events; maps don’t exist. And don’t expect exceptional physical prowess to guarantee a podium spot. Top athletes can watch competitors pass them by when, just before the finish line, they fail to spear a target or solve one side of a Rubik’s cube.

“It’s that excitement factor, the unknown, that makes it so challenging but fun at the same time,” says Hobie Call, the winningest Spartan racer of all time with 17 victories so far.

Do expect some fierce competition. Though the series began with less than 10,000 racers in 2010, more than 150,000 people will take on 34 events in 2012. The Spartan Races even won our Outside Reader Poll for best obstacle course series.

“It’s fun to watch and fun to do,” Call says. “Expect to have the time of your life.”

Ready to toss tires, jump through fire, and get pummeled by real life gladiators?

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