A former collegiate cyclist, Dan Ingolia, 32, grew up riding paved roads in Pennsylvania. But after the sales executive moved to Chicago, he spent a lot of time off two wheels. "I had to drive 20 minutes to get to roads that are safe to ride," he says. Then he discovered gravel grinding: trekking across miles of rutted, dusty gravel back roads—pedaling that requires serious core and upper-body strength. "It allows me to get off the grid, be self-sufficient, and test myself," Ingolia says. Now he does two or three 45-minute workouts midweek and three-hour tours on weekends—all on gravel, bridle, and limestone paths.
Midwesterners were the first to champion gravel grinders in the mid-aughts. Since then, the sport has gained traction (manufacturers like Giant and Raleigh recently launched grinding-specific gear) as brutal endurance tests like the Trans Iowa (up to 340 miles) and Kansas' Dirty Kanza (roughly 200 miles) have emerged. And the appeal is spreading—many of the 70-plus events already slated for 2014 are within a 90-minute drive of major cities, including Los Angeles, Atlanta, and Denver.
For many guys embracing the sport, getting an ass-whupping in a headwind is part of the allure. Nick Legan, 35, a public-relations manager from Boulder, Colorado, says he'd "been around enough type-A bike racers" when he heard about the Dirty Kanza. Although he began at dawn and finished post-dusk (after being blown off the road by sideways-falling rain—with another 100 miles to go), Legan is sold. "I prefer them for the communal, supportive environment," says the ex-road, -track, and -cyclocross racer. "It's not elitist out there."
That tri bike hanging from your rafters won't cut it; you'll need a specialized gravel-grinding model like the Niner RLT 9 4-Star ($3,000; ninerbikes.com) pictured above. It has a longer wheelbase, a lower center of gravity, and a more relaxed handlebar position than a road or a cyclocross bike for increased stability and extended comfort. Order it with gears or as a single-speed—which will make your ride even more grueling, if that's what you're into.