Jordin Sparks has worked her butt off for her new figure and now she's showing off the result on the August cover of Shape magazine.

The 22-year-old former "American Idol" winner makes her big-screen debut in "Sparkle," due out this summer, and poses for Shape in a teeny blue bikini, showing off her amazing 50 pound weight loss.

The rising star tells the magazine her physical transformation was sparked by the realization that at the age of 21, she was sick, always tired, battling a mild case of pneumonia and simply didn't feel healthy.

"I just wanted to be healthy. I remember thinking, 'I'm in my prime. I should be happy and fit.' That was the moment I decided that changes needed to be made," Sparks told Shape, explaining that she started slowly -- first walking around her neighborhood, then hiking and later joining a gym, taking Zumba classes and totally overhauling her diet.

Sparks first showed off her weight loss when she tweeted a photo of herself in a bikini back in 2011, and proved to herself that her hard work had paid off in more ways than one. After she posted the photo, Sparks received a phone call asking her to audition for the starring role in a remake of the 1970s musical “Sparkle," alongside Whitney Houston.

The film hits theaters on August 17 and the singer-turned-actress says she has high hopes to work in every facet of the entertainment industry:

“It may seem like I’m spreading myself a bit thin — no pun intended, but I love being creative and want to try a bunch of different things, like TV or another Broadway show," she told Shape.

PHOTO:
jordin sparks bikini weight loss shape cover

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  • July 2010

    Ali Lohan before .... Credit: Getty

  • September 2011

    Ali Lohan after .... The 17-year-old model looks undeniably different but still denies that she had any plastic surgery to alter her appearance.

  • November 2010

    Vienna Girardi before .... Credit: Getty

  • August 2011

    Vienna Girardi after ... The 25-year-old former contestant on "The Bachelor," admitted on Twitter that she'd gone under the knife to get a nose job. Credit: Getty

  • March 2010

    AnnaLynne McCord before ... Credit: Getty

  • November 2011

    AnnaLynne McCord after... This fall, the '90210' actress suddenly started busting out of her costumes with some new found curves. Credit: Bauergriffin

  • September 2010

    Bristol Palin before.... Credit: Getty

  • July 2011

    Bristol Palin after .... The former "Dancing With The Stars" contestant claims she had "corrective jaw surgery" and that's what is responsible for her new face. Credit: Getty

  • December 2010

    Christina Aguilera before.... Credit: Getty

  • November 2011

    Christina Aguilera after .... It's been a long time since the singer's "Genie In A Bottle" days, but fans were shocked to see some of the outfits Christina has been squeezing herself into. Credit: Getty

  • October 2010

    Jonah Hill before.... Credit: Getty

  • December 2011

    Jonah Hill after .... The "Superbad" actor looks like a completely different person after setting and meeting a goal to lose 30 lbs for his demanding role in the action-packed "21 Jump Street." Credit: Getty

  • November 2010

    Jordin Sparks before.... Credit: Getty

  • December 2011

    Jordin Sparks after.... The "American Idol" sixth-season winner dropped a ton of weight and seems thrilled to be showing off her new fit body. Credit: Getty

  • March 2010

    Kirstie Alley before .... Credit: Getty

  • September 2011

    Kirstie Alley after.... The actress and "DWTS" alumna turned heads when she lost 100 lbs this year. The 60-year-old's dramatic new look prompted rumors of weight loss surgery and an eating disorder, <a href="http://www.huffingtonpost.com/2011/09/21/kirstie-alley-denies-having-surgery-and-bulimia-after-losing-100lbs_n_974446.html" target="_hplink">both of which she denies having. </a> Credit: Getty

  • December 2010

    Kate Gosselin before .... Credit: Getty

  • October 2011

    Kate Gosselin after .... Though she denies having a facelift, the mother of eight doesn't quite look the same as she did last year. Credit: Getty

  • September 2010

    LeAnn Rimes before.... Credit: Getty

  • August 2011

    LeAnn Rimes after ... The 29-year-old country singer lost a shocking amount of weight this year and turned to Twitter several times to defend her super skinny body.

  • February 2010

    Raven Symone before... Credit: Getty

  • August 2011

    Raven Symone after ... The 26-year-old actress shed some major pounds in 2011. Credit: Getty

  • November 2010

    Ricki Lake before .... Credit: Getty

  • November 2011

    Ricki Lake after.... "Dancing With The Stars" helped the 43-year-old TV personality drop at least 23 lbs. Credit: Getty

  • December 2010

    Snooki before .... Credit: Getty

  • December 2011

    Snooki after ... The "Jersey Shore" star has been trying get to her goal weight of 98 lbs and it looks like she hit her goal. Credit: Snooki, Twitter

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