Bride-to-be Chelsea Clinton lost over 25 lbs. with spinning workouts (video)

Chelsea Clinton reportedly lost over 25 pounds by dieting and doing spinning workouts.
Chelsea, 30, will wed fiancé Marc Mezvinsky in Rhineback, NY, July 31, 2010. (Photo/Star)

Chelsea Clinton has been a workout fanatic in the days leading up to her highly-anticipated wedding to banker Marc Mezvinsky on July 31, 2010.

Clinton, 30, has been spotted leaving Soul Cycle workout studio in downtown Manhattan several times this week, where she reportedly took 45- to 60-minute spin classes every day.

'SHE'S A SIZE 2'

On some days, Chelsea was seen doing two classes in a row. [Editor's note: Spinning, an intense cardio workout that involves using a special stationary exercise bike with a weighted flywheel, can burn up to 500 calories an hour.]

“She’s in amazing shape cardio-wise,” a spin cyclist who took a class with Chelsea, told HollywoodLife. "She has incredible energy and is unbelievably well-toned. She’s tiny -- I’d say, she’s about a size 2.”

In addition to spinning, Clinton has also been spotted working out in the gym at the posh Tribeca apartment complex where she lives with fiance Marc Mezvinsky, 32. “I’ve seen them in the gym together working out," said a source. "Marc has a trainer — he’s very fit too, like Chelsea." 

(Chelsea Clinton wedding photos by Barbara Kinney/Matt McKenna via Getty Images)

What a difference a few years makes! Clinton, who overcame some awkward years in her adolescence and early twenties, has undergone a dramatic makeover, which experts attribute to weight loss, strict dieting, hair straightening, orthodontic work and plastic surgery.

VERA WANG DESIGNED CHELSEA'S WEDDING DRESS

Clinton, an alum of Stanford University, is currently a graduate student at Columbia University who previously worked at McKinsey & Co. Her equally brainy fiancé, Marc, an investment banker at 3G Capital Management who previously worked at Goldman Sachs.

Chelsea's $3 million wedding will take place July 31, 2010 at the former estate of John Jacob Astor IV in Rhinebeck, N.Y. The bride wore a custom-made Vera Wang wedding dress. Chelsea's incredible 500-pound wedding cake was gluten-free, 9-tiered and stood 4 feet tall. [See Chelsea's wedding pictures here]

Her parents, former President Bill Clinton and current Secretary of State Hillary Clinton, are both proud and happy. "I like him very much," said Bill, 63. "I really do. I admire him. Hillary feels the same way."

(In this video, Chelsea is seen going to and leaving a spin class this week):

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