Amy Palmiero-Winters is a long-distance runner. That would be hard work for most people. But Palmiero-Winters has a prosthetic leg.

PALMIERO-WINTERS: "People look at the shape of the foot and assume it has spring. All it does is absorbs the shock when my body pounds down."

Palmiero-Winters injured her left leg 16 years ago in a traffic accident. Doctors worked to save the leg, but decided to remove it below the knee. Later, she returned to running, but her replacement leg caused pain. Then, she went to A Step Ahead, a prosthetics center that Erik Schaffer founded.

ERIK SCHAFFER: "She was running nine miles (14.5 kilometers) an hour on the treadmill for 10 minutes and not even out of breath. And I didn't know what I had there, other than, wow, she is some athlete."

PALMEIRO-WINTERS: "And so I told him, I want to run 100 miles (161 km). And he didn't laugh at me. He didn't think I was crazy. He just looked at me and he's like 'All right.' He's like, 'Then that's what you'll do.'"

Palmiero-Winter has become a top runner because of legs built at A Step Ahead. She has won many honors, including the Sullivan Award. She often trains at night after her children are asleep. Recently, she won a 200-kilometer race in Arizona. During the day, she works at A Step Ahead, directing sports programs and helping young people like Diego Barcenas.

PALMIERO-WINTERS: "I want them to know that, you know, the only obstacles we have are the ones that we set for ourselves."

DIEGO BARCENAS: "I just really wanted to run again, just do everything a normal kid does. You know, I'm on the soccer team, and going to try out for the basketball team. So, I mean, I'm just trying to live my life like as if I have my both legs, and I pretty much do."

PALMIERO-WINTERS: "Not only is he trying out for the teams. He's doing very well at them. He's right up there with the other athletes."

PALMIERO-WINTERS: "And we're not disabled in any way. We're just athletes who compete with prosthetics."

Last summer, Amy Palmiero-Winters took part in a race of only five kilometers. The event included climbing up and down hills, over barriers and along walls. She did not win, but said she had fun.

PALMIERO-WINTERS: "Whew! New York makes them tough."