"It decides," he told The Early Show national correspondent Hattie Kauffman, "who's the fastest in the world. And it's a title that I've held for the last four years. So, I've learned so well to live with it.
"I wouldn't wanna live without it," he chuckled.
Shirley took home three medals: a gold, a silver and a bronze.
But, says Kauffman, he didn't stop there. He decided to take on a new mission: inspiring amputee veterans of the war in Iraq.
"The most emotional thing about standing on the podium was that my mother and father were there," he says.
Shirley didn't have a mother and father until he was ten years old. He told Kauffman about his years as an orphan when they met last summer.
"When I was three years old," he said then, "my mother left me on the streets of Nevada. …When I was five years old, I was put into an orphanage system. One of the gentlemen who was our caretaker was mowing the lawn. He was letting me jump on and off of (the lawnmower). And when he turned, I slipped on the lawn mower and had my accident. …Who in their right mind would let a child jump on and off a lawn mower?"
Shirley went from being an abandoned child, to a hometown hero. After the Paralympics, there was a parade in Shirley's honor. And he got to meet the president at the White House. Shirley has also gained major endorsements.
"Companies like McDonald's, when they put a paralympic athlete on that cup, I can't even tell you how many e-mails I got. …You know, just saying. 'This is awesome. This is unbelievable.' "
Shirley decided it was time to give back. He knew there were American soldiers returning from the war in Iraq as amputees -- soldiers like Sgt. Brian Wilhelm.
Last year, Wilhelm's leg was badly hurt in a firefight in Iraq. A rocket propelled grenade came into his vehicle and hit him and "just blew the hole in my leg."
It wasn't until he was at Walter Reed Army Medical Center that Wilhelm learned years of surgeries might not fully repair his leg. He had a tough decision to make: "I didn't want to dwell on being injured. I'd rather just do what I could and go back and do what I could to serve my country."
So he had the leg amputed.
Wilhelm met Shirley last month.
Shirley hopes his success can inspire soldiers who've become amputees in the line of duty. He's been meeting with many of them at Walter Reed.
"There's nothing I have to teach them about perservering or becoming a better person," Shirley says, 'cause these guys are awesome and these guys went over and protected us."
With a prosthetic leg, Wilhelm has not only rejoined his troops, he's running: "I've done the five mile in under 40 minutes," he told Shirely. "Well," Shirely responded, "I'll have to teach you something about how running that far is not worth it, dog," which was followed by both men laughing.
With Shirley's help, Wilhelm wants to compete in the 2008 Paralympics.
"We're talking about the Paralympic Games -- the second biggest sporting event in the world," Shirley points out.
Wilhelm told Kauffman it occurred to him that he could run "about two weeks after I started walking."
Shirley, meanwhile, wants to take his running to the next level: racing against able-bodied runners. Why? "it's because it will change the perception of people with disabilities…because it is a race. And it is sport."
Shirley could be competing in the 2008 Olympic Games in Beijing. His best event is the 100-meter dash.