Richard Simmons Dishes on David Letterman

Mike Krumboltz
Yahoo! TV

Richard Simmons, the outrageous fitness enthusiast and "Sweatin' to the Oldies" icon, is never subtle. In a new interview with Men's Health, Simmons comes out swinging at David Letterman.

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Fans of Letterman may have noticed that Simmons, once a frequent guest on "The Late Show," hasn't been on the program since 2006. According to Simmons, there's a reason -- Letterman isn't very nice to him.

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In the interview, Simmons said he loves Letterman, but called him "more complicated than any of them." When Simmons visited the show, he said he wasn't "allowed to talk" to Dave. Simmons said, "He's very standoffish. Then the commercials are over and you're back, you sit down again and finish the show. Maybe that's just how he is with me, I don't know. But I've never even had a chance to say goodbye to him."

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The interviewer commented that the talk show host "clearly adores" Simmons. But Simmons pushed back. "The last time I was on, we went to commercial and I was like, 'I'd love to meet your wife!' He (Letterman) was like, 'You never will.' And then I was like, 'And see your son!' And he was like, 'You'll never see him.' And then we come back from the commercial break and he's all friendly with me again. 'OK, we're back with Richard Simmons.' You think I'm kidding, but I'm not making this up." 

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While it isn't much of a stretch to think of Letterman as a bit of a grump on the set, he and Simmons do have a hilarious chemistry in front of the camera. Was it all an act, Dave? Say it ain't so.