@kourtneykardash / Instagram 1 / 10
@kourtneykardash / Instagram 1 / 10

Kourtney Kardashian is kicking it into high gear at the gym. The "Keeping Up With the Kardashians" star went makeup-free in a new selfie she took during a quick workout break on Jan. 14.

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"Day one," Kardashian, 34, wrote simply. Alongside the mirror snapshot, the mother of son Mason, 4, and daughter Penelope, 6 months, posed with her right leg up and her dark locks swept to one side. She gave a determined face for the camera as she wore tight-fitting workout pants, a white sports jersey t-shirt and neon green sneakers. During the same workout session she also posted a keek video of herself on a step machine. "Back at it!" she quipped.

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Of course Scott Disick's leading lady isn't the only Kardashian to take a selfie while breaking a sweat. This month alone, Kourt's most famous sister Kim has posted two booty selfies at the gym, with younger sister Kendall Jenner photobombing in the second.

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"Barging in on Kim's booty self," the 18-year-old model wrote on Jan. 10. In the snapshot, Jenner stood behind the 33-year-old as they both wore workout pants and sports bras.


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