The Little Rock swimmer, who was born with a genetic disorder called achondroplasia, a form of dwarfism, said she wanted to concentrate on other things after a career which saw her compete at three Olympics, winning a total of 19 medals.

Her most successful Games was at Athens in 2004 where she won seven gold medals, winning all the events she competed in and setting three world records.

It led to Popovich winningEPSN's 2005 ESPY Award for Best Female Athlete with a Disability. In addition, the Women's Sport Foundation named her SportsWoman of the Year.

Popovich had made her Paralympic debut at the age of only 15 in Sydney in 2000 where she won six medals, three gold and three silver.

At Beijing two years ago she claimed a tota of six medals, four gold and two silver.

"It has just come to that time," said Popovich.

"I have had a great 12 years, but it is time to move on.

"I have had a lot of fun and I wish that my body could go on forever; however, it is time that I start to focus on things outside of swimming.

Julie O'Neill, her coach, described Popovich as one of the best team leaders she has ever seen in any sport.

"She just really is very respected by her peers," she said.

"She has a great personality, is really outgoing, communicates well, and it is really easy for her to communicate with other athletes."

Popovich, who graduated from Colorado State University in 2007, hopes to become a physician's assistant.

"I have no doubt that whatever she ends up in she will be successful," says O'Neill..

"I hope that she is successful, happy and that she is doing something that she loves.

"She is such a great person and is so looked up to.

"I think her educational background and her experience in athletics is just going to help her make a huge impact in care-giving.

"If she can impact [care-giving] the same way she impacted the Paralympics, she will have a great career."

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