Jillian Michaels for Shape Magazine

Biggest Loser's Jillian Michaels is showing off just how in shape she is. The fitness trainer, 40, stripped down for Shape magazine's July/August issue, and revealed she feels better now about her body than she did 20 years ago.

"When I think back on my 20s and 30s, I look better now than I ever have. Yes, I'm older but I'm also wiser and that's a more intrinsic type of beauty," Michaels said.

Everybody's posing nude!

Michaels also discussed how being in shape is about more than just appearances. "It's important for women to have overall strength, because when you feel physically powerful, it transcends into every facet of your life," she said. "My best reason for having strong arms is because I love to pick up my kids."

"Do I want to have a better butt? Sure, but I'm healthy and can wear my skinny jeans, and that's good enough!" Michaels added.

Check out Michaels' revealing photo below.

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