"I love all the people who worry about me," Simmons said. "But it was time for me to take some time to be by myself. For the last 40 years I have been traveling, teaching classes, and I had a knee injury, so I had a knee replacement, which was very difficult for me… I have really just been taking it easy, staying at home, working out in my gym and doing the things I haven't done in a very long time."
According to Simmons, he's been keeping in shape despite concern that he might need another knee replacement. In response to speculation he has avoided going out because he has gained weight, Simmons said, "I still weigh 150. I work out every day. I have a gym at the house, and I am very healthy."
Simmons was last photographed in January 2014 by TMZ.
In November 2014, reports of Simmons' knee injury surfaced. Simmons took to Facebook then to thank his fans for their "outpouring of love and concern."
"I have had a tough time dealing with this injury, as it is keeping me from doing what I truly love to do and that is to teach classes around the world," he wrote. "Make sure you keep Sweatin'!"
The Sweatin' to the Oldies creator made his last public appearance in December 13, 2013, at SPARKLE: An All-Star Holiday Concert at ACME Comedy in Los Angeles.
"This is how I want to live my life right now,” Simmons told ET on Sunday. "And to all the people that are worried about me, please don't be. If I was in any trouble, if I was hurting in any way, I would reach out. It is time right now for Richard Simmons to take care of Richard Simmons."