Ice, mud, cold.

Hop on a road bike with knobby tires and crank hard around a marked off road course with ups, downs and all arounds. Don’t stop for an hour.

Welcome to cyclocross.

“It’s kind of like show up and throw up,” says cross racer and cycling coach Chad Cheeney. “Cross isn’t about practicing, it’s about showing up and racing.”

Cheeney is part of a subculture of cycling-, cult almost. Ride hard, fall harder and don’t give up.

“You’re on display,” he says. “You’re going to look like a buffoon sometimes. But it’s only an hour.”

Only an hour. Tight turns, steep climbs, swirling downhills, an all out effort on a thawing course of frosty slop that gets worse, never better.

So, what is a cross bike?

“It’s basically a road-looking bike with more frame clearance for knobby tires,” Cheeney said.

Tires are the No. 1 component that can make or brake a cross racer’s day.

Ben Sonntag, a pro cross and mountain bike racer, said brakes are the other weapon in the cross racer’s arsenal.

“Everyone wants disc brakes,” he says. “Way more predictable braking power.”

And don’t forget how to run with your bike. In cross, running is part of the game.