Richard Simmons left public life in 2014. As the fitness guru turns 75, he's 'happy,' his publicist says.

The fitness guru and his "Sweatin' to the Oldies" videos were everywhere in the '80s and '90s.

Richard Simmons pictured at the 87th Annual Macy's Thanksgiving Day Parade on Nov. 28, 2013, in New York City. (Photo: Laura Cavanaugh/Getty Images)
Richard Simmons pictured at the 87th Annual Macy's Thanksgiving Day Parade on Nov. 28, 2013, in New York City. (Photo: Laura Cavanaugh/Getty Images)

Richard Simmons, the once-ubiquitous fitness guru, is thriving as he turned 75 this week, his publicist, Tom Estey, said in a rare update about his client, whose birthday is July 12.

"This is a big milestone. I just want to see him happy, which he is," Estey told Entertainment Tonight and confirmed to Yahoo Entertainment.

Even that brief comment is more new information than we've heard about Simmons in recent years.

His career didn't start out that way. The owner of and big personality behind the cheekily named gym Slimmons, which opened in 1974 in Beverly Hills, was outspoken about his passion for fitness for decades. And his reach expanded far beyond his brick-and-mortar location.

His Sweatin' to the Oldies workout videos were all the rage in a decade of such unrelenting diet culture that leg warmers were fashionable. In total, he sold an estimated 65 million-plus exercise videos, tapes and DVDs, as well as cookbooks, inspired by his experience of having been overweight from childhood until he was a young adult, trying to make it as an actor in Hollywood. After he found his home — and health — in fitness, the always-effervescent Simmons played himself in shows and movies such as General Hospital, Fame, What Women Want and Arrested Development. He became so emblematic of staying fit that he appeared regularly on the talk-show circuit, and he was known for his regular, hilarious appearances on David Letterman's late-night shows. In 2008, he testified before a Congressional committee on ways to improve physical education in schools.

And then, suddenly, in 2014, Simmons disappeared. He stopped appearing in public, including teaching at his studio. There was concern, because it was so unlike him. TMZ reported in January 2015 that officers with the Los Angeles Police Department had conducted a welfare check after a concerned friend of his contacted the Los Angeles County district attorney's elder-abuse division. According to the outlet, officers found Simmons happy but exhausted after years of living an active celebrity life. He also had a limp, which was in line with a manager's comment at the time, that Simmons was depressed because of a knee injury. "I just want to spend time with myself," he reportedly said.

Still, that didn't sit well with some, and even some of Simmons's friends wondered why they hadn't heard from him.

Simmons felt compelled to call into Today in March 2016 to clear up rumors about where he'd gone and that he was being held against his will.

On World Fitness Day on May 1, 2010, Richard Simmons leads a class at the Georgia Dome in Atlanta. (Photo: Moses Robinson/Getty Images)
On World Fitness Day on May 1, 2010, Richard Simmons leads a class at the Georgia Dome in Atlanta. (Photo: Moses Robinson/Getty Images)

"No one is holding me as a hostage," he told the NBC morning show. "I just wanted to be a little bit of a loner for a while." He confirmed that he was recovering from an injuries to one knee, although the other was also giving him trouble after so much use over the years. "Not to worry, Richard's fine," he added. "You haven't seen the last of me."

Simmons made another public statement in November 2016, when his famous exercise studio closed its doors, although he did not attend the final classes.

"It's been over forty years now, and I am finally taking my own advice," he wrote, in part, in a Facebook post. "I am being kind to myself, and putting myself first. I am making changes and taking time to do the things I want to do. Please know that I am in good health and I am happy. No one has ever been able to tell me what to do and the same is true today. I am still independent, determined and opinionated. I simply am making a new beginning for myself — quietly and in my very own special way."

Still, his seclusion led to the 2017 podcast Missing Richard Simmons and continued theories about why he had left the spotlight so abruptly and where he'd gone.

When he turned 70, in 2018, a person described simply as a friend of Simmons, told ET that Simmons was keeping busy, just out of sight.

“He's doing very well. He's his jovial self," the friend said. "He spends most of his time at home and in his yard. ... He keeps up with his reading and does what he wants to do."