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Kim Kardashian - The reality TV star – who is expecting her first child with Kanye West – is trying to stay healthy with a plan by celebrity trainer Tracy Anderson. In a post on her blog, Kim writes, “She is helping me make the adjustments necessary to keep me feeling happy, healthy and most importantly create a workout plan that is safe for the baby." Kim shows off her sleek and sheer gym attire in head-to-toe black workout wear. (Photo: FameFlynet, Inc)

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Halle Berry - In order to maintain her killer shape, Halle turns to a trainer three times a week. “I do cardio, very light weights, and exercises that use a lot of my own body weight. I just try to keep everything lean and toned,” says the former Bond girl. She looks svelte (and stylish!) in this black tank and grey leggings with zipper details. (Photo: Jordan Lockhart, PacificCoastNews.com)

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Serena Williams - The tennis star is no stranger to sweat and style. To get summer ready, Williams says, "All you really have to do is a great 30-minute run or walk to get in shape for bikini season. Sometimes it's hard because you don't have the time, but it's tough and you have to get it in." As for taming your mane at the gym, she says, "It's hard. If you just embrace your natural curl and rock that, I think that's the best way to style it when working out." (Photo: Scott Barbour/Getty Images)

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Amber Rose - The soon-to-be mom knows that exercising helps relieve backaches, strengthens muscles and joints, and relieves stress brought on by pregnancy. Keep your workout outfits fun and it'll give you added motivation to get out and show off. (Photo: FameFlynet)

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Meagan Good - Still cute even after working up a sweat, the actress cools down with a smoothie in a funky tee, leggings, baseball cap and oversized shades. To stay slim and trim, Meagan says, “I jog about three or four times a week for 30 to 40 minutes. And I do squats so I don’t lose my booty.” (Photo: Fame Pictures, Inc)

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Ciara - Flaunt the figure you've worked so hard to get in a cropped tank top. Ciara targets her tummy by doing lots of cardio, crunches and "keeping my stomach squeezed in throughout the day." (Photo: FameFlynet, Inc)

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Mary J. Blige - The Queen of Hip-Hop Soul is ready to work, so she keeps cool during workouts with light-colored fabrics that wick away sweat and a cool cap and designer shades to protect herself from the sun. (Photo: Felipe Ramales, PacificCoastNews.com)

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Gabrielle Union - Stay hydrated no matter how you exercise. The 40-year-old actress says her number one beauty secret is drinking a gallon of water a day. Layers also help keep your body regulated throughout your fitness routine so you focus on completing reps instead of how uncomfortable you are. (Photo: Paul Morigi/WireImage)

Photo By Photo: Paul Morigi/WireImage

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Tyra Banks - Tyra rocks a zip-up top and three-quarter length sweatpants during her jog around New York City. She kept her hair out of the way by tucking it in a printed scarf and a cap. (Photo: Alo Ceballos/FilmMagic)

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Kelly Rowland - The singer, who works out her core by hitting the gym five to six times a week and doing abs work for 45 minutes, keeps her fitness style super comfy and lets her hair fly free. (Photo: FameFlynet)

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Angela Simmons - Fitness enthusiast Angela Simmons, who's preached on the benefits of going vegetarian and released a workout video with trainer Mike T. last year, shows off her tight thighs in these fit workout pants. (Photo: Owen Beiny / WENN.com)

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Zoe Saldana - A good pair of sneakers is a must. Choose one geared toward the kind of workout you'll be doing to cut down on foot pain, provide good support and absorb the shock. Zoe Saldana picks a black-and-white sneaker to match her black-and-white outfit. (Photo: Ralph, PacificCoastNews.com)

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Jennifer Hudson - The singer lost 80 pounds through healthy eating via Weight Watchers and exercise. She still fights off cravings, but stays in form by jogging and challenging herself at the gym. Mixing up fitness routines keeps your motivation up and those calories burning. (Photograph: Miguel Aguilar, ©PacificCoastNews.com)