The Keeping Up With The Kardashians star worked up a sweat with celebrity personal trainer Gunnar Peterson on Monday (22 September), and was seen leaving her session clutching water and a healthy juice drink.
Khloe didn't smile for photographers - not that we'd be beaming after a grueling workout she went as far as describing as "torture". Yikes.
The 30-year-old is trying to shift 10lbs she claims she gained while filming new TV show Kourtney & Khloe Take The Hamptons! over the summer.
Khloe and elder sister Kourtney relocated from LA to New York to launch a Dash pop-up boutique in the Hamptons, meaning Khloe was away from her trainer and her regular workout routine.
She's been more than making up for it since returning home, though. Not a day goes by when she isn't pictured leaving her gym.
Yesterday, her sombre mood may also have been to do with Kris and Bruce taking the official steps to end their 22-year marriage.
The couple shocked fans in October by announcing they'd separated, and today it emerged the split actually occurred the previous June.
Kris, 58, has now filed papers at Los Angeles Superior Court seeking a divorce from Bruce, 64, on the grounds of irreconcilable differences. She's also requested joint custody of their only minor child, Kylie Jenner, 17.
Despite their differences, Kris and Bruce have given everyone a masterclass in the amicable split, remaining firm friends and both still appearing side by side in Keeping Up With The Kardashians.
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