NEW YORK -- Former Olympic champion Bruce Jenner told the world that "for all intents and purposes, I am a woman" in an extraordinary television interview aired Friday about gender confusion he first felt as a youngster trying on his mother's and sister's dresses.

The 1976 decathlon champion, known better to a new generation as the patriarch of television's omnipresent Kardashian clan, took out his ponytail to let his long hair flow past his shoulders.

"I'm not this bad person," said Jenner, who hoped the two-hour interview could help others struggling with gender identity issues. "I'm just doing what I have to do."

The E! Entertainment network announced that Jenner would be part of a documentary series about the transition that would begin on July 26.

The two-hour interview with Diane Sawyer was filmed in February in Los Angeles and New York, before a fatal car accident in which Jenner was involved.

Jenner said he self-identifies as "her," not a specific name. But he told Sawyer he felt comfortable using the pronouns "he" and "him," a designation that is an important issue for many in the transgender community, which believes that transgender people should be referred to by the pronouns with which they choose to identify.

Jenner said his "brain is more female than it is male." He said he began gender reassignment therapy in the 1980s -- taking hormones, having surgery to make his nose smaller and having hair removed from his face and chest -- but gave it up. As Jenner, 65, got older, he realized that if he got sick and faced death without facing up to this issue, "I'd be so mad that I didn't explore that side of my life."

As a young boy, Jenner felt an urge to try on his mother's and sister's dresses.

"I didn't know why I was doing it," he said. "It just made me feel good."

Jenner said he has never been sexually attracted to men, and he wanted to make clear to viewers that gender identity and sexuality were separate things.

"I am not gay," he said. "I am, as far as I know, heterosexual. I've always been with a woman, raising kids."

Jenner said he has not decided whether he will undergo sexual reassignment surgery.

"These are all things that are out there in the future for me to explore," he said. "There's no rush for that. And I would do it so quietly that nobody in the world would know."

Jenner's four oldest children appeared on the interview special to support their father, but not the two girls he had with Kris Kardashian. He said his stepdaughter Kim has been a big supporter, urged on by husband Kanye West, but that his stepdaughter Khloe was taking it the hardest.

Jenner's first two wives offered messages of support; Kris Kardashian told ABC she had no comment but tweeted after the interview aired, "Not only was I able to call him my husband for 25 years and father of my children, I am now able to call him my hero."

Jenner told Sawyer that Kris was having a difficult time with it, and that if she better understood it, the couple would probably still be together.

Jenner's 89-year-old mother also was interviewed, saying she was more proud of Bruce than when he stood as an Olympic champion in Montreal.

The Transgender Legal Defence & Education Fund offered a statement of congratulations to Jenner.

"We hope that Jenner inspires others to find the courage to be open about who they are," said Michael Silverman, the fund's executive director. "And we hope that Jenner's message of authenticity and openness will shine a light on the unique challenges that transgender people face and help further equality."

Jenner showed Sawyer a closet filled with dresses and men's clothes. Sawyer said she had a private dinner with Jenner where he wore a dress, but the former Olympian did not appear in one in the ABC special.

Jenner said his two youngest daughters, suspecting that each other was secretly using her clothes, set up a computer to catch the other in the act -- only to find out it was their father raiding their closets.

"I would like to think that we can save some lives here," said Jenner, who admitted he once considered suicide at a low point when seen by paparazzi heading to a surgery to have his Adam's apple shaved back. "I have a feeling this is my cause in life. This is why God put me on this Earth, to deal with this issue."