Lance Armstrong competes in the Ironman Panama 70.3. triathlon in Panama City, Panama. Arnulfo Franco/AP hide caption

itoggle caption Arnulfo Franco/AP

Triathletes begin the 1,500-meter swim (just under 1 mile) in the Hudson River as part of last year's New York City Triathlon. Two race participants died during this year's swim portion. Dario Cantatore/Getty Images hide caption

itoggle caption Dario Cantatore/Getty Images