U.S. first lady Michelle Obama jumped, jived and waved her ams at a second birthday party for her “Let's Move” fitness and wellness initiative.

At a rally in Des Moines, Iowa, Thursday, the first lady led thousands of school children in a high-energy rendition of “The Interlude,” a dance created by students at the University of Iowa and popularized in videos on the Internet.

Mrs. Obama praised the students and the state for taking on her challenge to get healthier by starting community gardens, walking to school, and getting an hour of activity a day. She said eating well and exercising also “help your brain work better.”

Iowa has pledged to become the nation's healthiest state by 2016, as measured in a survey by the Gallup organization. The state currently ranks 19th in the latest poll in 2010.

The first lady also travels to Arkansas, Texas and Florida on her three-day tour to promote her campaign against childhood obesity.