Kourtney Kardashian Is A Golden Pin-Up Girl In Sexy Swimsuit

Sunday night's "Keeping Up with the Kardashians" followed the ever-expanding family on their vacation to St. Barts, in the first of two episodes documenting their Caribbean getaway.

To get her fans in the vacation spirit, Kourtney Kardashianshared three throwback snapsfrom St. Barts on her Instagram account. Channeling a '50s pin-up girl, the oldest Kardashian sister wore a gold one-piece bathing suit and nothing else, while she posed on a stationary exercise bike.

"We're in St. Barts on tonight's episode, wish I was there now," the mom of three captioned a photo of herself lounging by the pool.

Ever since hersplit with Scott Disickin July, Kourtney has beenworking on her fitness, Fergie style. Earlier that day, she shared a photo from her workout with sister Kylie Jenner, who Kourtney says has avoided exercising with her for six months.

Kourtney is clearly happy with all of her hard work, famously posing nude forVanity Fair's "Metallic Life" photo seriesback in October. She recently shareda previously unseen snapfrom the shoot, which features the reality star turned away from the camera, exposing her bare behind.

We've got a feeling 2016 is going to be Kourtney's year.

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