The model, 18, looked like she was enjoying a hike (that's American for a walk), as she was dressed in gym gear including trainers, leggins and a loose-fitting top.
But as she stretched her arms away from her body, Kendall's teeny tiny waist was on show.
She's not exactly a wallflower, so it wasn't long before the snap had made it onto Kendall's Instagram page!
Kendall is one busy lady right now.
Not only is she managing a busy career as a model, but she's also promoting Rebels: City of Indra, a new book she wrote with her sister Kylie Jenner.
The new series of Keeping Up With The Kardashian's is airing in the States, she and Kylie are promoting another fashion collection with US brand Pacsun... The list goes on.
So we're pretty surprised this lady even found time to get out and stretch her legs!
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