(CBS News) First Lady Michelle Obama is preparing to lead the presidential delegation at the kick-off of the 2012 Olympic Games Friday and, she said, this is an opportunity to encourage kids to improve their health and fitness.

"Leading our nation's delegation and traveling to London is truly a dream come true," Obama said on a conference call with reporters Monday. "Some of my fondest memories when I was young and not so young involved watching the Olympics on TV and cheering on Team USA."

Obama will lead a delegation that includes past U.S. Olympians such as Brandi Chastain, Dominique Dawes, Grant Hill and Summer Sanders.

The first lady, who has made fighting childhood obesity a priority with her "Let's Move" initiative, said the games are an opportunity to promote health and fitness.

"I decided I wanted to turn that Olympic spirit and inspiration into action by using these games as a way to get more kids up and moving."

Obama said she is excited to host a "Let's Move!" event for 1,000 American military children and American and British students Friday. The event, co-sponsored by the State Department and by Nickelodeon, will include sports stations, entertainment and appearances by Olympic and Paralympic legends.

She also declared July 28 "Let's Move! Olympic Fun Day," encouraging children and communities to cheer on Team USA and participate in athletic events across the country. At least 200 communities have signed up, and the number is expected to grow throughout the week.

While in London, in addition to her fitness campaign, Obama will also attend a reception for heads of state and hold a private meeting with Samantha Cameron, the wife of British Prime Minister David Cameron.

Deputy National Security Adviser for Strategic Communications Ben Rhodes said the trip is an important way for the first lady to continue building the special relationship between the U.S. and the U.K.

"While this visit is about the Olympics, its also about advancing the close ties between the U.S. and the United Kingdom," Rhodes said.

More here:
Michelle Obama says Olympics can promote health and fitness