Obstacle-Course Racing

The sport ends its most outrageous elements in a quest for longevity

Cycling and track athletes cause a stir when they're caught cheating—but in smaller (and less well-funded) arenas, others may be getting away with it

And goes small

A user's list for all the travel, fun, and affiliated delights you can cram into a year

The Olympic runner and his peers weigh in

With classic fundraising events on the decline, organizers are getting more creative—and the business of philanthropic racing is heating up.

Elite mud running champion Max King gives the lowdown on race-day attire.

There's no doubt that obstacle-course racing is growing at an explosive rate. In 2014, an estimated 10 million people competed in 5,000 events across 30 countries. In her debut book, Erin Beresini uncovers the growing sport's most compelling characters and provides the most authoritative insiders' guide to date.

Will leaping fiery hay bales amount to nothing more than an adrenaline-fueled fad? Or could it one day become an Olympic sport? That all depends on what comes next.