Richard Simmons — the energetic fitness guru whose “Sweatin’ to the Oldies” video series inspired people across the globe to improve their health – has passed away. He was 76.

On Monday, Howard remembered Simmons — who had 64 memorable Stern Show appearances — as a friend. “I’m heartbroken about this one … Richard was the best,” he said. “I really did love the guy and certainly what he gave my audience — he gave it his all.”

Howard also recalled Richard’s countless acts of kindness off the air — including visiting Stern Show executive producer Gary Dell’Abate’s ailing brother in the hospital. “Richard was really a stand-up guy,” Howard noted.

Co-host Robin Quivers revealed the “wonderful conversation” she had with Richard just a month before he died. “One of the last things he said to me was, ‘If you ever need anything, and I mean anything, you call me,’” she recounted. “Two days later, five dozen roses appeared at my home.”