In capturing gold at the London Olympics last year, both Allyson Felix and Sanya Richards-Ross overcame a nemesis. For Felix, 27, it was Jamaican sprinter Veronica Campbell-Brown. Felix had finished second to Campbell-Brown in the 200 meters at both the 2004 and 2008 Games. This time Felix allowed the Jamaican just an instant in the lead before accelerating in the final 50 meters to win with daylight. "I kept thinking, Be aggressive,&Shoes & GearDon't let up."

For Richards-Ross, 27, her own body had long stood in her way. For five years, she had suffered an autoimmune illness that caused fatigue and joint pain that only recently abated. In London, she was third coming out of the final turn in the 400 meters, and briefly flashed back to the 2008 Games and the crushing disappointment of fading in the homestretch to finish third. Would this be a repeat performance? "Just as quickly, I thought, No way. I've worked too hard at this," she says. "I'm the best in the world. I'm ready for this moment."

In addition to their individual laurels, Felix ran the second leg of the world-record-setting 4 x100-meter relay, and the two sprinters teamed to win yet another gold in the 4 x 400-meter relay. The wins were part of an inspiring American track performance that brought home 29 medals, six more than in 2008.

At the top of their game, both Felix and Richards-Ross are also at the top of their sport. "They are two of the most popular track athletes in the world," says Jill Geer of U.S.A. Track & Field, the sport's governing body. "They have the total package--talent, intelligence, grace, charisma. They're great examples on and off the track of how to conduct your life."

Indeed, both Felix and Richards-Ross embrace their status as role models to aspiring athletes (and their combined nearly 200,000 Twitter followers). Felix is a member of the President's Council on Fitness, Sports, and Nutrition, and both she and Richards-Ross frequently speak to youth groups about staying motivated, working hard, and maintaining integrity.

Gold medals simply give Felix a bigger platform from which to spread that message of perseverance. She remembers her devastation upon learning that her idol, Marion Jones, took performance-enhancing drugs. "I never want a person to feel that way about me," she says. "Being a role model is a privilege."