Kayla Harrison, 21, and Travis Stevens, 26, are representing Team USA in judo. They train together.
Holley Mangold, 22, and Sarah Robles, 24, are making their Olympic debut on the U.S. weightlifting team.
Meet MK-squared. Mary Killman and Maria Koroleva will compete in synchronized swimming. The sport is part dance and part swimming. But they can never touch the bottom of the pool during their performance.
The 2012 Olympics run from July 27 through Aug. 12. You can watch all the action on KPRC Local 2.