80s fitness star Richard Simmons breaks silence after news of TMZ documentary

Flamboyant fitness guru Richard Simmons was everywhere you looked for three decades - then he suddenly vanished. Photo / AP

Richard Simmons has broken his silence.

Following the release of a new documentary investigating the public disappearance of the 80s fitness icon, Simmons has broken his silence with a post on Facebook.

The 74-year-old has taken to his official Facebook page to thank fans for their "kindness and love".

In a post that has been confirmed as authentic by his manager Michael Catalano, Simmons posted a photo of a smiling emoji holding a thank you flag, and wrote, "Thank you, everyone, for your kindness and love! Love, Richard."

Catalano told People Magazine, "This was a personal post from Richard. He was moved by the reaction to the special and all the good wishes that he received. He was encouraged by the kindness."

Fans of the star quickly rushed to the comment section to offer their well wishes, with one fan commenting, "We miss you Richard but hope you are doing what is right for you. You have given me so much joy for years, it is your time now, you deserve peace and happiness."

Richard Simmons thanks fans for their support. Photo / Facebook

It comes after TMZ released a documentary investigating the public disappearance of the eccentric entertainer in 2014.

Many wild rumours circulated about where the fitness star was – including being held hostage by his housekeeper and gender reassignment surgery. However, the documentary has found a rather simple reason.

Titled TMZ Investigates: What Really Happened to Richard Simmons, the documentary has alleged the star cannot leave his home due to a birth defect.

TMZ managing editor Fabian Garcia said: "Something that happened to him at birth is directly connected to his disappearance - a birth defect that significantly affected one of his legs.

"He was born without a full set of bones in his foot and it causes physical and emotional problems."

The producer of the film, Charles Latibeaudiere, went on to declare the fitness star turned to food amid the pain and, in turn, "gained a lot of weight", which only put him in more pain.

Fox also reported the star was told by a doctor in 2014 that he needed a left knee replacement and if he didn't have one he may never exercise again.

The documentary claimed the knee replacement was "the key" to Simmons' disappearance.

"The prospect of surgery, of becoming sedentary, caused Richard to sink into a deep depression."

News of the star's knee troubles first made headlines in 2014, with TMZ reporting in the documentary that he underwent a right knee replacement which left him in a considerable amount of pain.