U.S. gymnasts, from left, McKayla Maroney, Jordyn Wieber, Kyla Ross, Gabrielle Douglas and Alexandra Raisman arrive at the MTV Video Music Awards on Thursday, Sept. 6, 2012, in Los Angeles. (Photo by Matt Sayles/Invision/AP)
Olympic gold-medal gymnast Aly Raisman waves to the crowd during a parade in her honor in Needham, Mass., on Sunday, Aug. 26, 2012. Raisman, 18, won two gold medals and a bronze at the London Summer Olympics. (AP Photo/The Boston Herald, Faith Ninivaggi) BOSTON GLOBE OUT; METRO BOSTON OUT; MAGS OUT; ONLINE OUT
In this photo provided by CBS, from left, Kyla Ross, Jordyn Wieber, McKayla Maroney, Aly Raisman and Gabby Douglas, members of the United States women's Olympic gymnastics gold medal-winning team, join television show host David Letterman on the set of the “Late Show with David Letterman,” Tuesday, Aug. 14, 2012, in New York. (AP Photo/CBS, John Paul Filo) MANDATORY CREDIT; NO SALES; NO ARCHIVE; FOR NORTH AMERICAN USE ONLY
In this photo provided by CBS, from left, Kyla Ross, Jordyn Wieber, McKayla Maroney, Aly Raisman and Gabby Douglas, members of the United States women's Olympic gymnastics gold medal-winning team, join television show host David Letterman on the set of the “Late Show with David Letterman,” Tuesday, Aug. 14, 2012, in New York. (AP Photo/CBS, John Paul Filo)
In this photo provided by CBS, from left, Kyla Ross, Jordyn Wieber, McKayla Maroney, Aly Raisman and Gabby Douglas, members of the United States women's Olympic gymnastics gold medal-winning team, join television show host David Letterman on the set of the “Late Show with David Letterman,” Tuesday, Aug. 14, 2012, in New York. (AP Photo/CBS, John Paul Filo)
U.S. gymnast Alexandra Raisman displays her gold medal during the podium ceremony for the artistic gymnastics women's floor exercise final at the 2012 Summer Olympics, Tuesday Aug. 7, 2012, in London. (AP Photo/Gregory Bull)
U.S. gymnast Alexandra Raisman performs Aug. 7, 2012, during the artistic gymnastics women's floor exercise final at the 2012 Summer Olympics in London. (Associated Press)
U.S. gymnast Alexandra Raisman performs Aug. 7, 2012, during the artistic gymnastics women's floor exercise final at the 2012 Summer Olympics in London. (Associated Press)
U.S. gymnast Alexandra Raisman displays her bronze medal for the balance beam during the artistic gymnastics women's apparatus finals at the 2012 Summer Olympics in London on Aug. 7, 2012. (Associated Press)
