What makes Olympian Allyson Felix run?

(CBS News) What was different about the 2012 Olympics in London that saw American Allyson Felix claim the gold medal in the 200-meter after several Olympics as the silver medalist?

It was the bitterness of the 2008 loss in Beijing to Jamaican Veronica Campbell-Brown that motivated the 26-year-old Californian in London.

In a pre-Olympics interview with Vanity Fair, Felix said of the haunting race, "I'm always thinking about it. I don't want to get that thought out of my head, because it does motivate me. But it's tough."

To make Felix's victory even sweeter, Campbell-Brown, who beat Felix out of gold in Athens in 2004 as well as Beijing, placed fourth in London. Jamaica's Shelly-Ann Fraser-Pryce, who won the 100 four nights earlier, took silver and American Carmelita Jeter added bronze to go with her silver in the 100 meters.

"I think it (the 2008 race) was all for a reason," Felix told the Associated Press after her London victory. "It kept me motivated and it made this moment very special. It was a big weight being lifted."