American fitness guru and recent internet obsession Richard Simmons has emerged from a public hiatus to receive treatment for severe indigestion.

According to his representative, the 68-year-old was hospitalised in California on Monday.

“After a few days of battling severe indigestion and discomfort while eating, we agreed it was best for him to seek treatment,” his spokesman Michael Catalano told ABC News.

Simmons, who achieved fame after founding a weight loss gym named Slimmons in California, has been the subject of numerous internet rumours in recent years.

The speculation began after Simmons appeared to withdraw entirely from public life in early 2014.

At the time, he attributed his reclusiveness to a knee injury, writing in a post on his Facebook page: “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.”

However, Simmons failed to reappear for the ensuing two years and in March 2016 The New York Daily News published a report quoting “concerned friends” who claimed he was being held hostage in his own home by his housekeeper.

Simmons’ publicist Tom Estey denied the report, insisting the aerobics instructor was merely “taking a break from the public eye”.

In November 2016, Slimmons closed after 42 years of business.

Growing concern turned to obsession when filmmaker, TV producer and Slimmons devotee Dan Taberski created a popular podcast titled Missing Richard Simmons last month.

Dan Taberski talks about his podcast Missing Richard Simmons

Taberski, who took Simmons’ classes religiously, refused to accept Simmons was simply on hiatus given his passion for his work and his close relationships with so many of his clients.

The podcast soon became the most popular in the world but ended abruptly after six episodes with Taberski admitting it seemed as though Simmons had simply retired.

“He just doesn’t want to be that guy anymore,” Taberski admitted defeatedly. “And that’s it.”

The Los Angeles Police Department also announced it had conducted a welfare check at Simmons’ house and found nothing of concern.

Most recently, Simmons’ brother Lenny, 70, spoke to People Magazine to address rumours the beloved fitness instructor was unwell or undergoing gender reassignment surgery.

“He’s not sick,” Lenny said. “There’s nothing medically wrong with him at all. These things about him transitioning to a woman are ridiculous. My wife Cathy and I were out there for Christmas and spent five days with him and I can assure you, he’s not transitioning into anything but himself.”