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MIRANDA LAMBERT: HALF-ING IT ALL
About to turn the big 3-0, the country crooner took a step toward staying forever young by dropping a dress size. Her trick? Portion control. "I haven't given up everything!" the singer told PEOPLE. "I try to just cut everything in half." To stay fit on the road, Lambert now brings her trainer on tour with her. "We do cardio, a lot of circuit training. We do things with my body weight, like lunges," she says. And while Lambert didn't cut out the foods she loves, there was one thing that needed to go. "Just Cheetos mostly!" she says.
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TRISHA YEARWOOD: ZUMBA
Cutting back on favorite comfort foods is tough when you're a best-selling cookbook author, but the Grammy winner worked up a sweat at Zumba classes at least three times a week to whittle away a whopping 30 lbs. – which she debuted in a form-fitting dress at the Academy of Country Music Awards in April. "I fell in love with it!" Yearwood says of her new exercise regimen. "My butt and my waist are smaller, and I like seeing that in the mirror!" she adds. "But I also feel great." Though the singer says she's designed her own plan that's low-fat, low-sugar 90 percent of the time, she still allows a splurge. "Occasionally, I have the mac and cheese," she says.
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CHRISTINA AGUILERA: TIME OFF
She's got The Voice, but now Xtina also has the physique. Taking a break from her judging role on the reality competition did her body good, as seen when she debuted her "Genie in a Bottle"-era figure. "She has been trying new types of foods and exploring new methods of exercise. Not for diet or weight, but more for her mind and well being and overall sense of good health," a source told PEOPLE of the star's hot new look.
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CHAZ BONO: NEW LIFESTYLE
The former Dancing with the Stars contestant (and Cher's son!) lost more than 70 lbs., down from 250 lbs., after a year of hard work that included plenty of exercise and Freshology-delivered meals. "I've been sticking to a really strict diet," he told PEOPLE. "It's not any type of starvation thing. I'm just cutting out a lot of stuff and eating primarily protein and vegetables and fruit." And the effort has been worth it. "Everything is easier, everything physically is easier, everything feels better and emotionally I just feel more comfortable, more confident,” Bono said in September.
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ROB KARDASHIAN: TWITTER
Looking to shed 50 lbs. (reportedly gained after his breakup with singer Rita Ora), Rob turned to a platform most fitting for a Kardashian – social media! Chronicling his workouts and diet on Twitter and Instagram, the reality star worked his way toward his desired 200 lbs. By May, Kardashian was already looking svelte and stylish in Las Vegas, and in November he posted a pic of his slimmer-than-ever face.
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NICOLE "SNOOKI" POLIZZI: PERSONAL TRAINER
She sashayed to an even smaller shape on Dancing with the Stars, but Snooki made her way into skinny girl territory before she put on her first sparkly costume. The reformed party girl and new mom dropped nearly 50 lbs. after the birth of son Lorenzo last September (the baby weight, and then some!), thanks to regular workouts. "I go [to a trainer] four times a week, and we do legs, arms and everything," the reality star told PEOPLE. "And after every one-hour workout, I do an hour of cardio … It's a good feeling to work out because I feel much better. Plus, my guy Jionni likes it."
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KELLY OSBOURNE: EATING BACKWARDS
The Fashion Police co-host has dropped about 70 lbs. since she began a weight-loss program in 2009, which she told Cosmopolitan Body "was just one benefit of putting the hard work in and sorting myself out on the inside first through therapy." Though she admits, "when I started exercising I couldn't even do one sit-up," she now exercises regularly – whether it's hiking, hola-hooping or dancing with friends. Osbourne has also discovered a trick to help her enjoy her favorite foods in moderation. “I eat my fattiest meal in the a.m. If I'm craving pizza, I'll have it for breakfast, salad for lunch, and oatmeal for dinner,” she told Self.
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LA LA ANTHONY: 60 DAYS OF FITNESS
She lifts! She boxes! She spins! And the hard work paid off – after joining a 60 Days of Fitness, a program kickstarted by rapper The Game and his brother (a trainer), the reality star dropped 15 lbs. – a journey she documented on Instagram. “It’s 60 days straight of working out and eating well," Anthony told the New York Post of her two-month body boost, which included three-mile runs in L.A.'s Runyon Canyon and curbing her milk chocolate addiction.
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BOY GEORGE: FREER NUTRITION
It was an '80s throwback when the Culture Club singer Tweeted a photo of his slender new shape. The 51-year-old credits Freer Nutrition as his secret, along with bursts of exercise he's broadcast to his fans. And the British star is clearly eating up the attention, along with his healthy meals: "I love that the size of my a-- is trending worldwide!" he wrote.
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JASON SUDEIKIS: "AT HOME" WORKOUTS
Attribute this fitness fad to the passion of a new romance. "The truth is, I'm not getting up an hour earlier and walking on a treadmill. I have the greatest workout partner in the world. And you don't need a gym membership for that kind of workout," the actor confessed to Elle, crediting his weight loss to fiancée Olivia Wilde. But beyond the bedroom, the other room of interest is his kitchen. "A lot of it comes from tiny things, like not eating barbecue sauce with my pizza at two in the morning," he adds. "I think it's all a manifestation of being happy and wanting to treat myself well."
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JASON SEGAL: FRIENDLY INTERVENTION
All it took was a caring assistant – and damning photo evidence – to help the How I Met Your Mother star lose 30 lbs. "My lowest moment came [when] I shot a movie in New Orleans," he told David Letterman. "New Orleans is like, the best food and booze anywhere … I really took advantage of it." When his assistant found him in the morning passed out in his hotel room, covered in Taco Bell wrappers with his belly in full view, "she took a bunch of pictures to show me what I had become," Segel admits.
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STEPHENIE MEYER: RUNNING
The Twilight author turned to revved-up cardio to reach her svelte new shape. "I used to be more an elliptical-and-weights girl but I've started running in the last year and I hate it and love it at the same time," the writer told PEOPLE. And luckily, she's found a jogging buddy to help keep her motivated: "My sister is a big runner and she's so excited [I've started running]. She wants me to run races with her now."