Deano / Splash News 1 / 3
Deano / Splash News 1 / 3

By Drew Mackie

Fitness celebrity Jillian Michaels is moving on to other gyms, she announced this week.

Michaels has appeared as a team leader on the NBC weight loss reality series, "The Biggest Loser," since it debuted in 2004 and remained for all but one of the show's eleven seasons. But as reported by Today, the upcoming season, which premieres Jan. 4, will be her last. "Season 11 of Biggest Loser will be my last :) have to finish out my contract," she tweeted on Dec. 7.

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Michaels went on to tweet to her followers that she will "focus on becoming a mommy and doing more charity work." She also noted that her work on her other NBC reality series -- "Losing It," which ran this summer and which focused on her helping entire families lose weight -- helped her to realize that she wants a family. "Last 2 years...Shooting 'Losing It' also had big impact on me. Living with kids I saw firsthand what I was missing," she tweeted.

NBC had no comment on Michaels's departure.

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