updated 2:36 p.m. ET April 19, 2005

AUGUSTA, Ga. - While watching a cycling race on TV recently, Lance Armstrong hardly acted like someone who was considering retirement.

“I couldn’t sit down the entire race,” said Armstrong, who then faced a tough question from girlfriend and rock star Sheryl Crow.

“She said ‘Look at you. You can’t even sit down. How are you going to retire?”’ Armstrong said. “It’s a great question.”

Armstrong will soon find out the answer. At a news conference Monday, he said he is retiring after this Tour de France, a three-week race ending July 24.

“I have to tell you I am 100 percent committed and the decision is final,” he said.

The cycling great will end a career in which he inspired millions by overcoming testicular cancer to win his sport’s signature event a record six straight times. He said his will to win a seventh straight Tour de France is boosted “by that dream to go out on top. That’s a big deal to me.”

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“It will be the last one, win or lose,” the 33-year-old Texan said. “While it is an older man’s race, it’s not an old man’s race.”

Armstrong said having to spend a month away from his three children recently helped seal the decision.

“That was much more difficult than it had been before,” he said. “They are at a stage now where they change daily, if not hourly. ... It’s time for me to not miss key moments in their lives.”

Still, come next year, Armstrong knows he’ll probably want to climb back onto the bike.

“I’ll definitely have the itch now and again,” he said.

Speculation regarding Armstrong’s future had grown in recent months, fueled by his comments about his children and his desire to increase efforts in raising awareness and funds for fighting cancer.

“Ultimately, athletes have to retire ... the body doesn’t just keep going and going,” Armstrong said.

Armstrong said having to answer persistent accusations that he has used performance-enhancing drugs had nothing to do with his decision. Armstrong has sued a former personal assistant, Mike Anderson, who said he found a banned substance in the rider’s apartment last year.

Monday’s announcement came on the eve of Armstrong’s defense of his Tour of Georgia title. The six-day, 648-mile event he uses as a tuneup for the Tour de France begins Tuesday in Augusta.

Armstrong said the Georgia race could be his last professional one in America, though he left open the possibility of racing in May at another practice event before the Tour de France.

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“If there’s a good local race, I’m more than happy to jump in,” he said.

Stan Holm, executive director of the Tour of Georgia, called Armstrong “a true hero and inspiration to people all over the world.”

Armstrong was attracted to the Tour of Georgia’s support for the Georgia Cancer Coalition, the official beneficiary of the race. Tour of Georgia officials have received more than 500 media credential applications this year, almost twice last year’s total.

Armstrong said he decided to make the announcement now, instead of closer to July, so he could “be up front and honest with the media, the people, the fans, not just here in America and in Europe.”

Armstrong’s announcement came the same day former teammate Tyler Hamilton was suspended from cycling for two years for a blood-doping violation. The Olympic gold medalist forfeits all competitive results since Sept. 11, 2004, the day of the positive test at the Spanish Vuelta.

“In my heart, I find it very hard to believe that he did that,” Armstrong said Tuesday on NBC’s “Today” show.

Armstrong’s new two-year contract with Discovery Channel team requires that he race just one more Tour de France. He says he will continue to work as an “adviser and an ambassador” for the team.

“I think we can move forward,” he said. “I think we can develop a winner and I’ll just be asking to come along and ride in the car at the Tour de France.”

And, he added, “I might not be able to sit down.”

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