Forty-two and fabulous.

Jennifer Lopez showed off her taut, tan tummy in Uruguay Thursday. She waved happily while heading to a casting for her and future ex-hubby Marc Anthony's reality show Q'Viva: The Chosen. 

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Although she had on jeans with her cropped red top, the singer-actress did some kicks and martial arts moves on the beach. According to Just Jared, she was practicing capoeira, a Brazilian art form combining martial arts, sports and music.

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After the birth of twins Max and Emme (now three years old) in February 2008, Lopez worked hard to shed 50 pounds. "You get to the point where you're like, Where am I? What happened to me? I got to get myself together for my kids, you know? They need to know what I really look like," she told Us Weekly last year. 

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Although she got "back to the size I was before I had the babies," Lopez said her "rib cage" shifted while carrying her son and daughter. "Before I was always able to fit into sample-size clothes from designers, and now they have to take them out just a bit...It's no big deal."

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