Often called "the race of truth," the time trial is a simple race: man (or woman) against the clock.

That's where the simplicity ends. There are team time trials (TTT) or individual time trials (ITT), which is what we'll see at the USA Pro Cycling National Championships.

While almost everyone know what a road bike looks like (drop handle bars, narrow tires, etc) a time trial bike is a completely different machine.

The handlebars are typically aero bars, placing the rider in a lower, extended and more aerodynamic position on the bike with their hands and arms out in front, much like a ski racer.

The bike frame itself has a sleeker design, with the tubes shaped like airfoils.

The wheels are typically very deep, which prevents the spokes churning up the air and creating turbulence, which results in drag. The rear wheels are usually disc wheels, again to provide a more slippery path for the air to flow around the bicycle.

As for the rider, you'll see teardrop-shaped helmets, and skinsuits with different weaves of fabric to avoid any drag which would result in a slower time.

The bikes, while state-of-the-art, are notorious for two important points: they handle poorly and they are uncomfortable to ride.

Riders sacrifice comfort for a lower time. There's a saying among cyclists: "If you're comfortable on a time trial bike, you're doing it wrong!"

The race has riders starting at timed intervals, usually 2-3 minutes apart so the rider is alone physically and mentally.

Pro-levels riders spend a lot of training time on time trails, since almost every major race has a time trial component. A poor result in a time trial in a multi-day stage race can almost certainly prevent a rider from being atop the podium at the race's end.

If you're at the time trials Saturday, look for the riders warming up, usually on stationary trainers and almost always in the shade. They don't hit the pavement cold, but will warm up for several hours before heading out to compete in a 30-minute time trial.

When they finish, they will be spent, leaving no gas in the tank. You'll see them collapse after finishing, usually from complete physical exhaustion.

But being a pro means they must recover quickly, since they'll be competing in the road race two days later. Teams have their own cooks, massage therapists and soigneurs, who handle nearly anything riders need. Soigneurs is French for "one who provides care."

The winner of the time trial and the winner of the road race can both be U.S. National Champions, since they are considered different disciplines of the sport.