Brent Sparkman has mounted a task to finish what is considered the toughest mountain bike race in the world.

La Ruta de los Conquistadores, or The Route of the Conquerors, was recently rated by Time magazine as one of the ten most difficult tests of human endurance on the planet.

"I honestly think La Ruta chose me more than I chose it. I was looking for a challenge that was something more than a marathon or riding 100 miles on a bike. But if I knew then what I know now, I might not have chosen La Ruta."

The four day treck is more than just a cycling event. It's an adventure race, that takes those who dare, through 9 microclimates and up 24,000 feet of Costa Rican terrain.

Of the more than 300 who start , about half drop out during day one.

"The mental aspect is tough. Just managing a ride on a bike for 8-10 hours, the nutrition aspect," said Sparkman. "This is a four day race, you can't leave it all on the course on day one or you'll have a tough time."

Via Skype, Brent and the man who created la Ruta set up his training schedule and a computer system attached to his bicycle records his efforts.

For eight months he's put in 12-15 hours of bike time each weekend and another 12-15 during the week.

He's fighting an uphill battle since the average slopes he'll climb in Costa Rica are more than twice as steep as his most difficult practice slope in Tallahassee.

But he says he's ready.

"I'm going to finish the four days. After all of the commitment from friends and family, they'll have to carry me off the course before I don't finish, I guarantee you that," said Sparkman.