Kate Middleton has always been active. She played field hockey in school and has been known to play a match or two of tennis.

But the real secret behind her svelte and toned body? It turns out, it's yoga.

In the latest issue of US Weekly, a source reveals several of the Duchess of Cambridge's pregnancy secrets, including her workout routine. According to HollywoodLife.com, the magazine found out Kate has swapped her daily runs for Shavasana. The 31-year-old even has a yoga instructor visit her at the palace says EntertainmentWise.com.

The mom-to-be reportedly took up the bendy activity as a way to stay healthy throughout -- and after -- her pregnancy says Yahoo.

Of course, Kate isn't the first person to take up yoga to improve their health. Everyone from Jennifer Aniston to Sting are advocates of the Zen-like activity.

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  • Lady Gaga

    <a href="http://www.huffingtonpost.com/jean-fain-licsw-msw/self-compassion_b_861494.html" target="_hplink">Lady Gaga's yoga teacher</a> has instructed the performer to be kind to herself. Gaga says, "My yoga teacher Tricia always says: 'Please try every day to have 15 minutes of compassionate thoughts by yourself.'"

  • Jon Bon Jovi

    Last year, <a href="http://www.menshealth.com/celebrity-fitness/jon-bon-jovis-best-list" target="_hplink">Bon Jovi told <em>Men's Health</em></a> that yoga was his preferred choice of workout, claiming to be a "21st-century man."

  • Madonna

    Everybody knows Madonna as a yogi. And she won't let us forget -- who remembers a few years ago when the Queen of Pop was <a href="http://www.dailymail.co.uk/debate/article-1340134/RICHARD-KAY-Queen-pop-enrages-upper-class.html" target="_hplink">caught doing her practice in the aisle of an airplane? </a>

  • Matthew McConaughey

    <a href="http://www.thesuperficial.com/matthew_mcconaughey_gets_his_y-02-2009" target="_hplink">Craving some photos of Mr. McConaughey in action?</a> <em>The Superficial</em> has got you covered.

  • Michelle Williams

    <a href="http://www.fitsugar.com/Michelle-Williams-Covers-Marie-Claire-Launching-Yoga-Single-Moms-Program-Boston-13198506" target="_hplink">Michelle Williams credits yoga for giving her "relief like nothing else."</a> She is a co-founder of the <a href="http://yogaforsinglemoms.com/" target="_hplink">Yoga For Single Moms</a> project in Boston.

  • Heather Graham

    The star tells<em> Zimbio </em> <a href="http://www.zimbio.com/Celebrity+Interviews/articles/182/7+Questions+Heather+Graham" target="_hplink"> "I do yoga</a> three times a week and I do pilates twice but I like yoga the best."

  • Sting

    Sting and his wife, Trudie Styler, have been practicing yoga together for about 20 years. They once told <em>Yoga Journal </em> that <a href="http://www.yogajournal.com/lifestyle/3006" target="_hplink">yoga has brought them closer as a couple.</a>

  • Jennifer Aniston

    Aniston got in shape for her recent flick,<em>Wanderlust</em>, with a combination of yoga and other workouts. <a href="http://www.shape.com/celebrities/celebrity-workouts/jennifer-anistons-yoga-workout" target="_hplink">Check out her routine on Shape. </a>

  • Willem Dafoe

    Dafoe is a long time yogi and has even been featured on some yoga VHS's (yes, that long).

  • Ellen DeGeneres

    <a href="http://www.fitsugar.com/Ellen-DeGeneres-Shape-May-2010-Cover-8097508" target="_hplink">Ellen practices slowly,</a> telling <em>Shape </em> that it is challenging for her to "slow down, to sit, to breathe and hold poses."

  • Gwyneth Paltrow

    According to <em>People,</em> Paltrow <a href="http://www.people.com/people/gwyneth_paltrow/0,,,00.html" target="_hplink">"wakes up at 4:30 each morning to practice yoga."</a>

  • Dennis Quaid

    Quaid has taken a hint from his yoga-obsessed ex (Meg Ryan) and practices often.

  • Christy Turlington

    <a href="http://www.oprah.com/oprahradio/Christy-Turlington-on-Yoga" target="_hplink">Turlington is a huge yoga advocate and has been practicing since her teens.</a> She even applied yoga's breathing methods during her natural childbirth to ease the pain. As she tells<em> Oprah</em>, "In terms of pain management, my breathing was the best thing I could do to manage pain on that level."

  • Ricky Martin

    Martin squeezes in a daily does of Kriya yoga into his busy schedule. He tells <em>People</em>, "I just ask people, <a href="http://www.people.com/people/archive/article/0,,20133136,00.html" target="_hplink">'Can I have 20 minutes for myself so I can just breathe?'" </a>

  • Adam Levine

    <a href="http://www.details.com/health-fitness/celebrity-workout/201112/maroon-5-adam-levine-yoga-workout-video" target="_hplink">Adam Levine does yoga on the go.</a> He mentioned to <em>Details</em>, "At any Maroon 5 concert, you'll see a room backstage marked yoga."

  • Brad Pitt

    <a href="http://www.azcentral.com/ent/celeb/articles/2010/12/12/20101212brad-pitt-angelina-jolie-couples-yoga.html" target="_hplink">Rumor has it</a> that Brad Pitt and Angelina Jolie do couples yoga together.

  • Sarah Jessica Parker

    SJP tells <em>Good Housekeeping </em> that she is <a href="http://www.goodhousekeeping.com/family/celebrity-interviews/sarah-jessica-parker-jul06" target="_hplink">"fortunate enough to have things like private trainers and yoga classes.</a>"

  • Russell Simmons

    Just look at Simmons' twitter feed (<a href="https://twitter.com/#!/unclerush" target="_hplink">@unclerush)</a> and you'll find yoga inspiration all over. This month he wrote, "The mind is like a monkey in a cage,it will jump around,when it realizes that the cage will not move it will settle, sit be patient #yoga."

  • Drew Barrymore

    In 2009 <em>Popsugar </em> caught <a href="http://www.popsugar.com/Photos-Drew-Barrymore-Tie-dyed-Leggings-Sunglasses-after-Yoga-Class-NYC-4191888" target="_hplink">Barrymore post-yoga in some interesting tie-dyed leggings</a> that she could really move in.

RELATED: The 7 Benefits Of Yoga

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  • Physical

    The movements of yoga will carve out a long, lean, strong, and confident body.

  • Mental

    All those deep breaths reset your mind back to its natural state: calm, focused, and sharp.

  • Psychological

    All the focusing inward illuminates our behaviors and tendencies. The same habits we have on our mat are the ones we have in our lives. We see this, and we gain the freedom of choice. Who do I want to be? We get to create or re- create ourselves each day. Regular practice gives you a clear mind and the inspiration and courage to be constantly expanding and improving your life.

  • Neurological

    When your brain is "on yoga" your neurological system is brought back into balance and is conditioned to steer you naturally toward a healthy lifestyle. Our bodies are constantly rewired to make whatever we practice get easier. When we practice healthy, balanced living we get more healthy, balanced living.

  • Intuitive

    When there is tension in the body and mind, your intuition gets buried and your body switches to survival mode. Your yoga practice makes space in your body physically, releases tension, and calms your mind, making room for your intuition to float to the surface and guide you.

  • Creative

    Creative juices start to flow when your body and mind begin to release mental blocks. Creativity doesn't like to come out when there are stressors, whether from physical tension or mental cloudiness. When the stress melts away, creativity can come out to play.

  • Connected

    Yoga is the practice of getting connected. However you choose to view your spirituality, when you practice yoga, you remember that we all are connected, here to help each other, and that we have so much potential when we are kind to others