The U.S. Anti-Doping Agency stripped Lance Armstrong's seven Tour de France titles Friday, erasing one of the most incredible achievements in sports after deciding he had used performance-enhancing drugs to do it. 
 
 FILE - In this July 24, 2005, file photo, overall leader Lance Armstrong signals seven for his seventh straight win in the Tour de France cycling race as he pedals during the 21st and final stage of the... (Associated Press) 
 
 FILE - In this July 24, 2005, file photo, Lance Armstrong holds the winner's trophy after claiming his seventh straight Tour de France cycling race during ceremonies on the Champs-Elysees avenue in Paris... (Associated Press) 
 
 FILE - In this July 6, 2010, file photo, Lance Armstrong grimaces prior to the start of the third stage of the Tour de France cycling race in Wanze, Belgium. Armstrong said on Thursday, Aug. 23, 2012,... (Associated Press) 
 
 FILE - In this Feb. 15, 2011, file photo, Lance Armstrong pauses during an interview in Austin, Texas. Armstrong said on Thursday, Aug. 23, 2012, that he is finished fighting charges from the United States... (Associated Press) 
 
 FILE - In this July 24, 2010, file photo, Lance Armstrong crosses the finish line during the 19th stage of the Tour de France cycling race, an individual time trial over 52 kilometers (32.3 miles), with... (Associated Press) 
 
 FILE - In this July 9, 2010, file photo, Lance Armstrong prepares to take the start of the sixth stage of the Tour de France cycling race over 227.5 kilometers (141.4 miles) with a start in Montargis... (Associated Press) 
 
 Armstrong, who retired a year ago, was also hit with a lifetime ban from cycling. An athlete who became a hero to thousands for overcoming cancer and for his foundation's fight against the disease is now officially a drug cheat in the eyes of his nation's doping agency. 
 
 In a news release, USADA said Armstrong's decision not to take the charges against him to arbitration triggers the lifetime ineligibility and forfeiture of all results from Aug. 1, 1998, through the present, which would include the Tour de France titles he won from 1999 through 2005. 
 
 Armstrong has strongly denied doping and contends USADA was on a "witch hunt" without any physical evidence against him. 

 AFP/Getty Images The U.S. Anti-Doping Agency stripped Lance Armstrong of his seven Tour de France titles and banned him from competition after the racer said he wouldn't contest charges he used performance-enhancing drugs. 
 
 Lance Armstrong was stripped of his record seven Tour de France titles late Thursday after he refused to fight allegations that he used performance-enhancing drugs. 
 
 Lance Armstrong refused to pursue doping allegations, which hinge on witness testimony. Who are the witnesses and is their testimony credible? Reed Albergotti and Vanessa O'Connell join The News Hub to discuss. Photo: Getty Images. 
 
 Once a trusted teammate of Lance Armstrong, Floyd Landis alleges that Armstrong's USPS cycling team was involved in an elaborate doping scheme. Simon Constable talks to WSJ's Reed Albergotti about the story. (Originally published July 2, 2010.) 
 
 Mr. Armstrong notified the U.S. Anti-Doping Agency that he wouldn't fight the charges the agency brought against him in June, a move that, according to USADA, immediately strips him of all of his athletic titles going back to Aug. 1, 1998, roughly a year before his first Tour de France victory. USADA said Mr. Armstrong is also banned immediately from competing in Olympic and other elite-level sports for the rest of his life. 
 
 Enlarge Image Close Reuters Seven-time Tour de France winner Lance Armstrong in 2010. 
 
 In 2010, The Wall Street Journal was the first to report that a former teammate had accused Mr. Armstrong of doping, which eventually led to the investigation by USADA. 
 
 USADA, a nonprofit organization charged with policing doping, doesn't have the authority to bring criminal charges, but it can sanction athletes by stripping them of their titles and banning them from competition for doping. 
 
 Mr. Armstrong had until midnight Thursday to officially decide whether to fight the agency's charges, which alleged Mr. Armstrong had participated in a conspiracy to cheat. 
 
 In a statement, Mr. Armstrong didn't admit that he cheated, but said he won't fight USADA, an organization Mr. Armstrong has said for months has treated him unfairly. 
 
 "Say what you will about what I did or didn't do ten years ago, they're not playing by the rules," Mr. Armstrong said in an interview with The Wall Street Journal earlier this summer. "Here's the deal, athletes cheating in sport, that's bad. But what these guys are doing is far worse. The levels they have gone to try to f— me and rig this thing are far worse than any athlete taking a transfusion or some EPO. This is far dirtier." 
 
 By opting not to fight—a move that took many by surprise—Mr. Armstrong gave up the chance to defend himself against the charges in an arbitration hearing. 
 
 The governing body for the sport of cycling, known as the UCI, could appeal the sanctions, though it has never appealed a sanction handed down by USADA. The UCI could also refuse to acknowledge USADA's sanctions, though that would be unprecedented. 
 
 "There comes a point in every man's life when he has to say, 'Enough is enough,'" Mr. Armstrong said in a statement Thursday. "For me, that time is now. I have been dealing with claims that I cheated and had an unfair advantage in winning my seven Tours since 1999." 
 
 Mr. Armstrong's lawyers Timothy J. Herman and Robert Luskin wrote in a letter Thursday to USADA that Mr. Armstrong's decision didn't reflect "any belief that USADA's charges have merit or any fear of what a fair proceeding would establish." 
 
 Throughout his career, Mr. Armstrong was dogged by allegations that he had used performance-enhancing drugs. In 2010, Mr. Armstrong's former teammate, Floyd Landis, sent a series of emails to cycling officials in which he made allegations of doping on Mr. Armstrong's former cycling team and accused Mr. Armstrong of doping during his career. The existence of the emails was first reported by The Wall Street Journal. 
 
 Enlarge Image Close AFP/Getty Images Lance Armstrong crosses the finish line of the 91st Tour de France cycling race in 2004. 
 
 Mr. Armstrong has always firmly denied the charges, often lashing out at his accusers and asserting that he had passed more than 500 drug tests. USADA's case against him rests largely on the testimony of at least 10 former teammates who USADA has said stand ready to say Mr. Armstrong doped during his career. 
 
 Mr. Armstrong was diagnosed with testicular cancer in 1996. He came back to win the sport's biggest race—the Tour de France—in 1999. He went on to win six more Tour de France titles in a row, beating the previous record of five. Mr. Armstrong's autobiography, "It's Not About the Bike," was a best seller. 
 
 Mr. Armstrong retired in 2005 and came back to the sport for the 2009 season. Initially, he agreed to enter into a special blood-testing program to prove that he was racing clean. He ultimately ended the program, citing high costs and logistical problems. 
 
 Mr. Landis's allegations led to a federal criminal investigation that was dropped in February. In June, USADA announced it was bringing doping charges against Mr. Armstrong and five other people affiliated with his former team. 
 
 Write to Vanessa O'Connell at Vanessa.O'Connell@wsj.com and Reed Albergotti at reed.albergotti@wsj.com 

 The organizers of the Tour de France say they will wait to see what happens before commenting on Lance Armstrong's case. 
 
 FILE - In this July 24, 2005 file photo, Lance Armstrong gestures from the podium after winning his seventh straight Tour de France cycling race, as second-placed Ivan Basso of Italy, left, and third-placed... (Associated Press) 
 
 FILE - In this July 24, 2004, file photo, overall leader Lance Armstrong, right, of Austin, Texas, follows compatriot and teammate Floyd Landis, left, in the ascent of the La Croix Fry pass during the... (Associated Press) 
 
 Armstrong said Thursday that he would not pursue arbitration in the doping case brought against him by USADA, causing his seven Tour de France titles to be stripped Friday by the American agency. 
 
 But the International Cycling Union says it wants USADA to explain why Armstrong should lose his titles. 
 
 Amaury Sport Organization, which runs the world's most prestigious race, said Friday that it would not comment until it had heard more from both of the bodies.
– The US Anti-Doping Agency has officially stripped Lance Armstrong of his seven Tour de France titles and banned him from the sport for life for doping, after saying it would do so last night. That announcement came after Armstrong dropped further challenges to USADA accusations that he used performance-enhancing drugs to win the premier bike race from 1999 to 2005, reports the Wall Street Journal. "There comes a point in every man's life when he has to say, 'Enough is enough,'" Armstrong said in a statement. "The toll this has taken on my family and on me leads me to where I am today—finished with this nonsense." Though Armstrong has admitted nothing, dropping his fight is viewed by the agency as an admission of guilt, notes AP. Armstrong insists the USADA has no authority to strip him of his titles, though agency head Travis Tygart says it does. The decision could be appealed by the International Cycling Union, the governing body of the sport, but it has never before challenged a decision of the USADA. The UCI this morning said it will wait for the USADA to explain why Armstrong should be stripped of them before commenting on the case, noting the World Anti-Doping Code requires this in cases "where no hearing occurs." Tour de France organizers are also holding off on commenting.