AP Exclusive: Lance Armstrong won't fight USADA charges

AUSTIN, Texas -  Lance Armstrong says he will no longer fight charges from the U.S. Anti-Doping Agency that he used performance-enhancing drugs during his unprecedented cycling career, a decision that could put his string of seven Tour de France titles at risk.

Armstrong says he is innocent, but announced Thursday night that he has decided against fighting USADA because he is weary of the doping accusations that have dogged him for years. His decision could lead to a lifetime ban from cycling and perhaps the loss of the Tour titles he won from 1999-2005.

USADA says Armstrong used banned substances dating to 1996, including the blood-booster EPO and steroids, as well as blood transfusions. Armstrong sued in federal court to block the charges but lost.

The 40-year-old Armstrong retired from cycling in 2011.