Fitness Guru Richard Simmons is rumored to battle depression. NY Daily News reported the fitness expert's rep said that the health expert is "sad" due to a knee injury but contests reports that "he has been a shut-in for almost a year due to paralyzing depression over his health and the death of his pet."

Friends close to Simmons lashed the claims that he is okay. According to TMZ, "close friends are now mad, in addition to being extremely concerned for his welfare."

The spokesman told the NY Daily News that Simmons is not "clinically depressed."

"The dog passed away a year and a half ago, it's not the issue. And he hasn't lost weight recently either. He's presently at the same weight he was when he released his first 'Sweatin' to the Oldies' video. The truth is very simple, he has a knee injury, and it's serious enough to keep him from doing what he loves most: exercising and motivating others. He is not clinically depressed or a shut-in or a recluse. It would be like Tiger Woods having a shoulder injury that stopped him from golfing, but in this case it's compounded by a thousand because Richard has dedicated his life to others, and right now he can't exercise or travel and take his message to the people in person," Thomas Estey told the Daily News.

"He's saddened and nervous about the knee thing, but he's going to proceed with it, and he'll be back. He's going to be back and better than ever, when he's ready," Estey added.

However, TMZ noted that close friends of Simmons are "pissed" and they are not buying the idea. Here are some reasons why they believe their friend is not in a good psychological state:

-- The last contact any of his closest friends had with him is March 10.

-- The mother of an extremely close, long-time friend died a few months back, and Richard never contacted her, which is completely out of character.

-- Richard was close with Joan Rivers and, as one friend put it, "There is no way he wouldn't have gone to her funeral if he was OK."

-- He has abandoned his exercise studio, where he was a fixture. He hasn't been there in months, and everyone there says they have no idea why.

"If Richard is really OK and is aware people are extremely concerned about him, he'd pick up the phone and tell them to relax. But he hasn't, and we're worried sick," a friend said according to TMZ.