"I needed a good workout today," Kardashian captioned another snap.
Jenner, meanwhile, has felt fit and festive this week. The 18-year-old reality TV star shared a throwback clip of her completely freaking out over a Christmas gift, reminding us all that she was once just an innocent kid.
"I hope I get this excited this Christmas lol," she captioned the video on Saturday.
Earlier this month, Kylie got in the holiday spirit by decking out her Ferrari -- a gift that was given to her by Tyga for her 18th birthday -- with reindeer ears and a red nose. Watch the video below to hear more.