And secrets to how they sculpted them.
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It’s obvious why so many people want in on reality TV star Bethenny Frankel’s Skinny Girl secrets. Frankel, spotted here with husband Jason Hoppy on February 27, 2011 in Miami, certainly has a taut tummy, thanks in part to her Body by Bethenny yoga DVD and regular cardio sessions on the elliptical.
Just before the season 2 premiere of Bethenny Ever After, the first-time mom revealed on TODAY that she had suffered a miscarriage. The emotional experience will not be seen on her reality show, but you can expect the same snarky one-liners and career success that drew you in during season one.
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90210 star AnnaLynne McCord flaunts her toned tummy at a beach BBQ on July 19, 2009, in L.A. Click here to see what McCord told Shape about her laidback approach to staying fit.
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Halle Berry knows exactly how to accentuate her abs. The actress is seen here at the Fragrance Foundation's Fifi Awards on May 25, 2011, in NYC.
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Twilight stud Kellan Lutz works up a pretty good sweat taking his pup for runs. Lutz, spotted on the beach in St. Maarten on April 10, 2010, credits circuit training for his washboard abs.
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When you think of Gwen Stefani, you think of her band No Doubt, her L.A.M.B. fashion line, and her washboard abs. The pop star, seen on tour in Singapore on September 25, 2009, is open about working hard for her body. Click here to find out how Stefani and more super-fit music stars train to take center stage.
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David Beckham's buff bod is stealing the spotlight from his soccer skills. Beckham shows off his rock-hard abs after a Los Angeles Galaxy game in Honolulu, Hawaii, on February 20, 2008.
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Rihanna's risqué wardrobe demands a tight tummy. The singer is seen here in Oakland, California, on June 30, 2011. When Rihanna isn't burning calories on stage, she stays fit the old fashioned way: cardio, weight training, and a healthy diet. (Click here to see Rihanna’s favorite energy-boosting snacks.)
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Actor Robert Buckley's abs are undeniable. Buckley is spotted shirtless in NYC on June 27, 2008.
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While the world is enthralled by Kate Middleton's wardrobe as she and Prince William tour North America, we can't forget what she looks like in a bikini! This photo was taken back in 2006 while Middleton vacationed with Prince William in Ibiza, Spain.
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Ryan Phillippe's six-pack abs are the result of working out with a trainer for more than ten years. The actor, seen here on the beach in Puerto Rico on September 5, 2010, does everything from intense weight training to cardio to plyometrics.
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Matthew McConaughey’s abs have become a staple of summer (and every other season). The actor, father, and fitness machine is seen here on Miami Beach back in 2006.
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With all of the moving and shaking that Shakira does on stage, it's no wonder that she has some of the best abs in the business. The Colombian songstress, seen performing in China on December 31, 2010, credits belly dancing and workouts with celeb trainer Tracy Anderson for her famous midsection.
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TV host and Dancing With the Stars favorite Mario Lopez has been making girls swoon over his abs since his days on Saved by the Bell. Lopez is seen here participating in the Nautica Triathlon in Malibu on September 13, 2009.
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With the revealing wardrobe she rocks, Lady Gaga's body has to be at its best at all times. The superstar, seen here leaving the Late Show with David Letterman in NYC on May 23, 2011, hits the gym for sweat sessions with celeb trainer Harley Pasternak, who told us his top tips for keeping all of his A-list clients in amazing shape.
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It isn't surprising that seven-time consecutive Tour de France champion Lance Armstrong has a pretty impressive set of abdominals. The cyclist is seen here suiting up in the 2010 Tour de France race.
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Actress and Victoria's Secret model Rosie Huntington-Whiteley was named Maxim's "Hottest Woman on Earth," and it's not hard to see why. The Transformers: Dark of the Moon star is seen here, perfect tummy and all, on the VS Fashion Show runway on November 10, 2010.
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Kate Hudson, pictured here on April 30, 2009, in NYC, has the kind of body confidence that most women kill for, not to mention some pretty impressive oblique muscles. One of Hudson’s secrets for looking and feeling flawless? Staying super hydrated—which you can do by snacking on these tasty hydrating foods.
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Gilles Marini is the second Dancing With the Stars alum to make the list. The actor is seen here filming for Brothers & Sisters on September 18, 2009, in Pasadena, California.
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Want to know how reality star Audrina Patridge gets those killer abs? The July 2011 Shape cover model, spotted here in Las Vegas on April 3, 2010, told us her top 4 moves for sexy abs.
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Raphael Nadal has one of the best games and hottest bodies in tennis. Nadal and his killer obliques are seen here on the beach in Spain on July 29, 2010.
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It's hard to pick Blake Lively's best feature, but her flat abs are certainly a standout! Lively, spotted here in NYC on July 28, 2010, keeps her core strong by doing planks and using a stability ball. (See more of Lively’s best workout secrets here!)
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We picked Nicole Scherzinger as 2010's celebrity with the sexiest abs. The singer and Dancing With the Stars champ, spotted performing in New Jersey on September 13, 2010, doesn’t use any equipment for her abs exercises. Check out her workout here.
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Gavin Rossdale joins wife Gwen Stefani on our best celebrity abs list! Rossdale's six-pack is on display at a charity tennis tournament in Delray Beach, Florida, on November 4, 2007.
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Jessica Biel is a shoe-in on nearly every “hot body” list. The actress, seen here in L.A. on June 3, 2010, is no stranger to the gym (get her body-toning plan here) and does back extensions using a stability ball, push-ups, and side planks to sculpt her midsection.