Michelle Obama participates in a tug of war with Jimmy Fallon in the Blue Room of the White House during a Late Night with Jimmy Fallon taping for the second anniversary of the White House Let's Move! initiativePhotograph: Chuck Kennedy - White House/ReutersTalk show host Ellen DeGeneres challenges First lady Michelle Obama to a press-up contest during a taping of The Ellen DeGeneres Show in BurbankPhotograph: Michael Rozman/APFirst lady Michelle Obama jumps with 400 children at an event on the South Lawn of the White House to launch a challenge to help break the Guinness World Records title for the most people doing jumping jacks in a 24-hour periodPhotograph: Yuri Gripas/ReutersMichelle Obama at a football clinic in Washington DC to highlight the Let's Move! campaign and the importance of children getting at least 60 minutes of active play each dayPhotograph: Jim Watson/AFP/Getty ImagesMichelle Obama dances during a surprise visit to Alice Deal middle school for a Let's Move! fitness event in WashingtonPhotograph: Molly Riley/ReutersThe first lady runs a 40-yard sprint for the Let's Move! campaign in New OrleansPhotograph: Gerald Herbert/APMichelle Obama uses a skipping rope at an event highlighting the work of the Physical Fitness Council at a school in WashingtonPhotograph: Pablo Martinez Monsivais/APThe first lady plays table tennis during a Let's Move! event at the Usta Billie Jean King National Tennis Centre in New YorkPhotograph: Samantha Appleton/The White HouseMichelle Obama exercises with a hula hoop during a healthy kids fair on the South Lawn of the White House Photograph: Haraz N. Ghanbari/APThe first lady plays hopscotch with students from the Make A Difference NGO, at Mumbai University in IndiaPhotograph: Punit Paranjpe/AFP/Getty ImagesMichelle Obama and children play double-dutch during a taping for the Presidential Active Lifestyle Award challenge and Nickelodeon's Worldwide Day of Play, on the South Lawn of the White HousePhotograph: Chuck Kennedy/The White HouseThe first lady and senator Harry Reid participate in a mountain stretch during the Let's Move Outside programme at Red Rock Canyon National Conservation AreaPhotograph: Isaac Brekken/APMichelle Obama exercises with children on the South Lawn of the White House in Washington during an event announcing the creation of a program to promote military family wellnessPhotograph: Chris Kleponis/AFP/Getty ImagesThe first lady runs across the South Lawn during an event to promote physical activity at the White HousePhotograph: Jim Young/ReutersMichelle Obama shows off her muscles along with the children at the DC River Terrace school at an event to promote physical fitness in WashingtonPhotograph: Evan Vucci/AP