By: CBS News Simone Biles is one of the most dominant athletes in the world. If that sounds like hyperbole, just listen to this. She hasn't lost a gymnastics all-around competition in eight years and in a sport where the top contenders are usually separated by mere decimal points, she wins by whole numbers. She also owns the most Olympic and World Championship gold medals combined of any gymnast in history. Biles had hoped to crown her career with more Olympic golds last summer and then retire. But when the pandemic postponed the Tokyo Olympics until this July, Biles reluctantly decided to train for another year. If, like most Americans, you only watch gymnastics once every four years during the Olympics, here's a glimpse of what you've missed.