Kate Hudson has found an “interesting” way to burn calories.

The 42-year-old “music” star has been a longtime supporter of weight Watchers – now known simply as WW – and frequently shares health and fitness tips with fans.

On Wednesday, he took to Instagram to do exactly the same.

“Just got some really interesting news that I’m really excited about,” she said in a brief video. “If anyone needs me, I’m going to be in the bedroom for good, I’d say – hour 20. If he can handle it.”

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Star said according to him To WW’s fitness app, “Having sex for 20 an hour … would equal six fitpoints.”

She continued in the caption: “Yeah, I said sex. Thanks @ww for always making sure we’re getting all the fit points.”

Fans had a lot to say in the comments too.

“Hour twenty!?!?!?!?!??” A follower said. “I hope you’re ready.”

Another extended “best wishes” to him and his partner, Danny Fujikawa.

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Hudson has rarely shied away from sharing personal details with her fans, starting earlier this year about her relationship — or lack thereof — with members of her family.

“We’re sitting here like we have the best family, like we’re great. And yet, we never accept the fact that we have four other siblings,” she told a January episode of her podcast. Said during “Sibling Revelation.”

Kate Hudson is a vocal supporter of Weight Watchers - now called WW.  (Photo by Daniele Venturelli/Danielle Venturelli/Getty Images for Bvlgari)

“So I was thinking of Hudson. It’s important to think that we reach out to all of our siblings and maybe engage with them a little bit.”

Hudson and her brother Oliver are the children of actress Goldie Hawn and musician Bill Hudson. Both are close to their mother and stepfather Kurt Russell, although they do not have strong ties with their biological father or their children.

The “Almost Famous” star also has a half-brother in Wyatt Russell and a half-brother in Boston Russell.