MALIBU, Calif. - Floyd Landis took the stand in his arbitration hearing yesterday, repeatedly denying he'd ever taken testosterone, saying it "wouldn't serve any purpose for me to cheat and win the Tour."

For 75 minutes, Landis gave a detailed breakdown of his career, then outlined the strategy he used for his riveting comeback in Stage 17 of last year's Tour de France - a plan hatched over dinner and whiskey the night before.

"It helps with the tactical plan," Landis said, drawing laughs.

Speaking under oath, he said the only banned substance he has taken during his career has been cortisone - medicine he used to treat his injured hip, which had been approved for his use by cycling authorities.

Landis, who is accused of using synthetic testosterone, tested positive after that 17th Tour stage.

He also spoke about allegations that Greg LeMond made two days earlier, acknowledging he was in the room when his former manager, Will Geoghegan, made the call to LeMond threatening to reveal the three-time Tour champion's secret that he had been sexually abused as a child.

"I knew there was a problem," Landis said of his reaction upon realizing Geoghegan had made the call. "I was traumatized having him tell me that story in the first place. There are very few things I can imagine would happen to a person that are worse than that. To make light of that, I can't even put words to it."

Landis described being confused when word of the positive test first came out last summer.

At a news conference in Spain, he explained his positive test came not because of testosterone use but was, rather, something that was produced "by my own organisms."

"I still don't know what that means," Landis testified. "I regret it. It was confusing at that point.

"I shouldn't have taken the advice of those lawyers. I didn't know what I was doing."