Jennifer Lopez Flaunts Her Post-Babies Body

Looks like Jennifer Lopez's intense diet and fitness regime is really paying off—the actress/singer/new mom's waist has made a bigger comeback than Robert Downey, Jr.!

Following her husband Marc Anthony on tour in Europe, Jennifer stepped out for some retail therapy in Madrid, Spain today wearing a flowy red dress cinched around the middle to show off her diminishing frame. Just a few days ago, the diva soaked up some sun in a belly-baring bikini while yachting in Tenerife with Marc and their infant twins Max and Emme.

We're dying to know what Jenny's doing to whip her body back into shape in such lightning speed—not even rail-thin Christina Aguilera rebounded so quickly!