An Ironman 70.3, also known as a Half Ironman, is one of a series of middle-distance triathlon races organized by the World Triathlon Corporation (WTC). The "70.3" refers to the total distance in miles (113.0 km) covered in the race, consisting of a 1.2-mile (1.9 km) swim, a 56-mile (90 km) bike ride, and a 13.1-mile (21.1 km) run. Each distance of the swim, bike, and run segments are half the distances of those segments found in an Ironman triathlon. The Ironman 70.3 series culminates each year with a World Championship competition, of which competitors qualify for during the 70.3 series in the 12 months prior to the championship race. In addition to the World Championship race, Ironman 70.3 championship competitions are also held for the European, Asia-Pacific, and Latin America regions.

From its inaugural year in 2006 until 2010, the Ironman 70.3 World Championships' was held in Clearwater, Florida, USA during the month of November. In 2011, the 70.3 Championship venue changed to Las Vegas along with date of the event moved up in the calender to September. Lake Las Vegas is the site of the event's swim.

Lance Edward Armstrong (born Lance Edward Gunderson on September 18, 1971) is an American former professional road racing cyclist who won the Tour de France a record seven consecutive times after having survived testicular cancer. He is also the founder and chairman of the Lance Armstrong Foundation for cancer research and support. He last rode for UCI ProTeam Team RadioShack, a team he helped found.

In October 1996 he was diagnosed as having testicular cancer with a tumor that had metastasized to his brain and lungs. His cancer treatments included brain and testicular surgery and extensive chemotherapy, and his prognosis was originally poor. He went on to win the Tour de France each year from 1999 to 2005, and is the only person to win seven times having broken the previous record of five wins shared by Miguel Indurain, Bernard Hinault, Eddy Merckx, and Jacques Anquetil.

In 1999, he was named the ABC Wide World of Sports Athlete of the Year. In 2000 he won the Prince of Asturias Award in Sports. In 2002, Sports Illustrated magazine named him Sportsman of the Year. He was also named Associated Press Male Athlete of the Year for the years 2002–2005. He received ESPN's ESPY Award for Best Male Athlete in 2003, 2004, 2005, and 2006, and won the BBC Sports Personality of the Year Overseas Personality Award in 2003. Armstrong announced his retirement from racing on July 24, 2005, at the end of the 2005 Tour de France but returned to competitive cycling in January 2009 and finished third in the 2009 Tour de France. He confirmed he had retired from competitive cycling for good on February 16, 2011.