The reality TV star let fans know that she is embracing 2014 by working on her health and her figure - and it sounds like she is trying out a new fitness regime to boot!
Heading to the gym yesterday (14 January), Kourtney tweeted that she was "back at it" on the stair master and uploaded a photo of herself stood amongst the machines in her workout gear.
In the picture we can see the petite brunette wearing a pair of black leggings, some neon Nike trainers and a cropped white T-shirt.
She also appears to be completely make-up free and has swept her mid-length brown locks to one side, while listening to some music in her earphones.
Kourtney captioned the snap: "Day one", implying that she would now be embarking on a planned exercise regime to whip her into shape after the Christmas holidays.
She followed the gym selfie up with an old magazine photo of herself wearing a bikini and wrote: "This is why I started working out today..."
The mum-of-two had a relaxing break over the festive period, spending quality time with her family, including her sisters, her longtime boyfriend Scott Disick and their children Mason and Penelope.
However, they weren't just lying around in their pyjamas beside the tree and overdosing on chocolates and cake.
Instead, the Kardashian-Jenner clan headed to Utah for a winter skiing holiday and hit the slopes in their warmest coats to burn off their turkey dinner and test out their skills.
The giant family was joined on the snowy trip by Kim's fiancé Kanye West and Kendall's rumoured new boyfriend Harry Styles.
Have you started a new workout routine for the new year? Let us know below, as the best comment from across the website each week wins £50!
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