Calling himself "deeply flawed," now-disgraced cyclist Lance Armstrong says he used an array of performance enhancing drugs to win seven Tour de France titles then followed that by years of often-angry denials.

"This is too late, it's too late for probably most people. And that's my fault," he said in an interview with Oprah Winfrey that aired Thursday night. "(This was) one big lie, that I repeated a lot of times."

Armstrong admitted using testosterone and human growth hormone, as well as EPO -- a hormone naturally produced by human kidneys to stimulate red blood cell production. It increases the amount of oxygen that can be delivered to muscles, improving recovery and endurance.

In addition to using drugs, the 2002 Sports Illustrated Sportsman of the Year admitted to Winfrey that he took blood transfusions to excel in the highly competitive, scandal-ridden world of professional cycling. Doping was as much a part of the sport as pumping up tires or having water in a bottle, Armstrong said, calling it "the scariest" that he didn't consider it cheating at the time.

The same man who insisted throughout and after his career that he'd passed each of the "hundreds and hundreds of tests I took" contended in the interview that he wouldn't have won without doing what he did. While Armstrong didn't invent the culture of doping in cycling, he said, he admitted not acting to prevent it either.

"I made my decisions," Armstrong said. "They are my mistakes."

Armstrong: I was "a bully"

The first installment in his interview, which was conducted earlier this week with the talk-show host, aired Thursday on the OWN cable network and on the Internet. The second installment will be broadcast Friday night.

Armstrong admitted he was "a bully ... in the sense that I tried to control the narrative," sometimes by spewing venom at ex-teammates he thought were "disloyal," as well as suing people and publications that accused him of cheating.

He described himself as "a fighter" whose story of a happy marriage, recovery from cancer and international sporting success "was so perfect for so long."

"I lost myself in all of that," he said, describing himself as both a "humanitarian" and a "jerk" who'd been "arrogant" for years. "I was used to controlling everything in my life."

The scandal has tarred the cancer charity Livestrong that he founded, as well as tarnished his once-glowing reputation as a sports hero.

Those who spoke out against Armstrong at the height of his power and popularity not only felt his wrath but the wrath of an adoring public.

Now, with Armstrong stripped of endorsement deals and his titles, those who did speak out are feeling vindicated.

They include Betsy Andreu, wife of fellow cyclist Frankie Andreu, who said she overheard Armstrong acknowledge to a doctor treating him for cancer in 1996 that he had used performance-enhancing drugs. She later testified about the incident and began cooperating with a reporter working on a book about doping allegations against Armstrong.

Armstrong subsequently ripped her, among others. More recently, he said he'd reached out to her to apologize -- in what Andreu called "a very emotional phone call."

"This was a guy who used to be my friend, who decimated me," Andreu told CNN's Anderson Cooper on Thursday night. "He could have come clean. He owed it to me. He owes it to the sport that he destroyed."

In his interview with Winfrey, Armstrong said he understands why many might be upset that it took him so long to speak out, especially after going on the offensive for so long. He said he's reached out in recent days to several people, such as Andreu, who publicly accused him of doping and then were attacked -- and in some cases sued -- by him.

And the former athletic icon also conceded he'd let down many fans "who believed in me and supported me" by being adamant, sometimes hurtful and consistently wrong in his doping denials.

"They have every right to feel betrayed, and it's my fault," he said. "I will spend the rest of my life ... trying to earn back trust and apologize to people."