Career Highlights: Considered to have the best shot at a medal of anyone on the U.S. cycling team, Armstrong will compete in her third straight Summer Games. One of the true giants - male or female - in the history of cycling in the United States, Armstrong made her Olympic debut in 2004 when she finished eighth in the road race. Four years later, she returned to the Olympic stage and rolled to a victory in the time trial. A wife and mother, Armstrong again appears to be the favorite to win the time trial this summer, just days before her 39th birthday. The only American other than cycling legend Greg LeMond to win three world championship medals, Armstrong has enjoyed a stellar 2012 season leading up to the London Games. She defended her title in the time trial at the Amgen Tour of California, and also placed first at the Merco Cycling Classic in California and New Mexico's Tour of the Gila. Armstrong, no relation to seven-time Tour de France winner Lance Armstrong, finished second at the prestigious Tour of Flanders in Belgium in April. She switched to racing bikes full time after her budding career as a triathlete was cut short when she was diagnosed with osteoarthritis of the hips, forcing her to stop such high-impact activities like running. Armstrong briefly retired from cycling after the 2009 season while pregnant with her son, Lucas, but got back on the bike and in 2011 returned to the top of podium by winning the Sea Otter Classic.