The keto diet isn't the only trend Jillian Michaels has a problem with.

In a video filmed back in December but shared by Shape yesterday on the magazine's Instagram account, the personal trainer bashed CrossFit, listing multiple "issues" with the trendy workout.

"First of all, you’ve got what, maybe 20 to 25 movements that don’t really vary? And you’re doing them over and over and over again," she said. "So on one hand it stops being effective because you’re not challenging the body from various angles of push and pull, with different varieties of exercises and different types of movements that work different modalities.”

She continued, "And I know CrossFit (athletes say), ‘Oh, we work all the modalities!’ — but no, not really, so shouldn’t you choose a workout that has a little bit more flexibility and strength so you get more mobility, not just power, which is speed and strength.”

Instead, she advised a more balanced workout.

“A little agility work, maybe some endurance training,” she said. “So that you’re training in a more balanced way, to keep the body changing and keep your training more holistic by hitting all modalities of fitness.”

Shape shared the video on its website in December but the Thursday post on Instagram by the magazine quickly drew eyeballs, with negative reactions filling up the comment section.

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"I’d love to see her be thankful people are just out moving and working their bodies. How about a good job instead of u shouldn’t do this or that!" one user wrote. "My husband lost 70 lbs with CrossFit 6 years ago and has kept it off. I’d say it works pretty good."

"What DOES she like? Oh, just her programs? Gotcha," another wrote with an eye-rolling emoji.

"She only likes what she can make money off of. Simple," another said.

"She’s quickly turned into a crazy negative person. She bashes every thing," another wrote. "How about do what works for your body & you actually enjoy"

It's not the first time Michaels has gone after a health trend. The star, who rose to fame on "The Biggest Loser," ripped the keto diet in January.

She slammed the trendy weight-loss regimen tied to everyone from Al Roker to Halle Berry because she says it starves the body's cells of essential macronutrients.

"I don't understand. Like, why would anybody think this is a good idea?" Michaels told Women's Health at the time, calling the keto diet a "bad plan, for a million reasons."

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