Disgraced American cyclist Lance Armstrong said he was "humbled" and "ashamed" by the years he spent lying about using performance-enhancing drugs.

In the second part of his interview with Oprah Winfrey, which aired on Friday, Armstrong said he finally cracked after he saw his son defending him against allegations from anti-doping authorities.

"I feel ashamed. Yeah, this is ugly stuff," Armstrong told the talk show host.

Armstrong also told Winfrey he wants to take part in competitive sports again, even after being banned for doping and stripped of his awards.

"Hell, yes. I'm a competitor. It's what I've done my whole life. I love to  train. I love to race," Armstrong said.

"Not the Tour de France, but there's a lot of other things I could do. I deserve to be punished. I'm not sure that I deserve a death penalty."

Al Jazeera's Lee Wellings, reporting from the headquarters of cycling's governing body UCI in Aigle, Switzerland, said that the second section of the interview was far more personal than the first leg.

"This was more like the traditional confessions that we've seen before from other people who spoke to Oprah Winfrey in the past like Marion Jones and others," said Wellings.

"It was more about the family side, the emotions and an attempt from him to show some remorse. He knows he needs to do that. He is desperate to win back over firstly the American public and secondly the world."

Anti-doping authorities and disillusioned fans might have wanted a different explanation, perhaps while expressing deep remorse or regrets, though there was plenty of that in the interview.

'Don't defend me'

Armstrong said he did not break over the $75m in lost sponsorship deals, or after being forced to walk away from the Livestrong cancer charity he founded and called his "sixth child".

Neither, the cyclist said, did he crack after his lifetime ban from the cycling competition.

It was another bit of collateral damage that Armstrong said he was not prepared to deal with.

"I saw my son defending me and saying, 'That's not true. What you're saying about my dad is not true,'" Armstrong recalled. "That's when I knew I had to tell him."

Armstrong was near tears at that point, referring to 13-year-old Luke, the oldest of his five children.

It came just past the midpoint of an hour-long broadcast, a day after the disgraced cycling champion admitted using performance-enhancing drugs when he won seven straight Tour de France titles.

Critics said he had not been contrite enough in the first half of the interview, taped Monday, but Armstrong seemed to lose his composure when Winfrey zeroed in on the emotional drama involving his personal life.

"What did you say?" Winfrey asked.

"I said, 'Listen, there's been a lot of questions about your dad. My career. Whether I doped or did not dope. I have always denied that and I have always been ruthless and defiant about that. You guys have seen that. That's probably why you trusted me on it.' Which makes it even sicker,'' Armstrong said.

"And, uh, I told Luke, I said,'' and here Armstrong paused for a long time to collect himself, "I said; Don't defend me anymore. Don't."

Source: Al Jazeera and agencies