Sylvester Stallone reflects on steroid use and his dramatic ‘Rocky III’ transformation

Stallone said a heart valve replacement became a turning point in how he approached his physical training

Sylvester Stallone has reflected on the extreme physical preparation behind his role in Rocky III, discussing his past steroid use and the demanding routine he followed to change his physique for the film.

Speaking with journalist Tracy Smith at New York’s 92NY, Stallone discussed his new memoir, Steps, and recalled the lengths he went to while developing Rocky Balboa for the third instalment of the franchise.

Stallone said he wanted Rocky to appear significantly different after achieving fame and success. He described the character as becoming increasingly vain and protected before eventually being confronted by Clubber Lang, played by Mr T.

To support that storyline, Stallone said he undertook a major physical transformation. He recalled reducing his body fat dramatically while following an extremely restrictive diet that included tuna and large amounts of coffee. He also acknowledged using steroids during the process.

The actor later discussed the broader expectations surrounding action stars and superhero characters. Stallone argued that performers portraying physically enhanced characters often undergo substantial preparation to create an appearance that differs from an ordinary physique.

His comments come as he looks back on the physical toll associated with his decades of action roles. Stallone previously told The New York Times that he used steroids while making Rocky III and has spoken about the effects he believes the drug had on his body.

During his conversation with Smith, Stallone also recalled a significant health event that changed his approach to physical training. He said his wife, Jennifer Flavin Stallone, urged him to seek medical attention after noticing that he appeared unwell. Stallone subsequently underwent heart valve replacement surgery.

He described the experience as a wake up call and said he believes his wife’s intervention helped save his life.

The discussion was part of the first live instalment of a new series featuring CBS Sunday Morning at 92NY. The programme brings figures from arts, politics and culture before a live audience for extended conversations.

Stallone’s appearance also forms part of the promotion for Steps, his memoir about his life and career, including the creation and enduring legacy of Rocky, which marked its 50th anniversary in 2026.