Legendary fitness instructor Richard Simmons has died, according to a report.

Simmons, who turned 76 Friday, died just 24 hours after he thanked fans on social media for their birthday wishes.

The health guru, who stepped away from the public eye a decade ago, rose to fame in the 1970s and ’80s after opening several gyms across the country and releasing his iconic high energy fitness tapes.

His death was first reported by TMZ. Police told the outlet they believe it was a natural death.

Simmons revealed in March he had been diagnosed with skin cancer.

In a rare interview with People Magazine this week, he said he “feels good” despite his age.”I am grateful that I’m here, that I am alive for another day,” he said. “I’ll spend my birthday doing what I do every day, which is to help people.” 

The “Sweatin’ to the Oldies” star had announced earlier this year he was planning to open a Broadway musical with renowned producer and composer Patrick Leonard.

Simmons was beloved, and often parodied for his flamboyant, positive attitude that helped millions of Americans get in shape for decades.

He was the author of nine books, including the New York Times Best Seller, “Never Say Diet.”

Simmons was born in the French Quarter of New Orleans and was inspired to get healthy after weighing in at 268 pounds when he graduated high school, according to a biography on his website.

After taking control of his weight through healthy eating and exercise, he moved to Los Angeles in 1973 and would open his fitness studio, SLIMMONS, in Beverly Hills where he continued to teach classes until 2013.

His success as an instructor — and his bubbly personality — landed him appearances on local and then national television programs.

He launched his own nationally syndicated series, “The Richard Simmons Show,” which ran for four years and received numerous Emmy Awards.

Simmons’ 65 fitness videos sold more than 20 million copies.After Simmons announced his cancer diagnosis he pleaded with his followers on social media to “enjoy your life to the fullest every single day. Get up in the morning and look at the sky… count your blessings and enjoy.”

He concluded with some tips for living a healthy lifestyle, which included enjoying a desert “once in a while.””There is something else very important that you must do,” he added. “Tell the ones that you love that you love them. Hug those people and children who you really care for. A big hug really goes a long way.”