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Beyonce isn't letting having a baby slow her down. Despite giving birth to Blue Ivy Carter in January, Beyonce has been dazzling fans in her first post-baby concerts, a four-night concert series at Revel’s Ovation Hall in Atlantic City, N.J. Showing off her post-baby bod in a number of revealing outfits, Beyonce confessed to the audience that she had actually lost 60 pounds for the concert series.

"Y'all have no idea how hard I worked!" the 30-year-old said on stage. "I had to lose 60 pounds. They had me on that treadmill. I ate lettuce!" The Grammy winner showed off her new fighting form in four custom-made Ralph & Russo ensembles and shoes by Stuart Weitzman.

Related: Beyonce: I Definitely Want More Kids

Despite the major slim down, Beyonce assured fans she won’t be eating only lettuce for long. "Now tonight, I'm gonna get chocolate wasted!"

Saturday’s show was quite the star-studded event as Gayle King, Michelle Obama and daughters Sasha and Malia were all in attendance. Check out the video of Beyonce’s first post-baby, high-octane performance!