Osbourne's Fears Over Lengthy Tour

The Black Sabbath star, who previously endured a lengthy battle with alcohol and drug addiction, is due to perform in countries including the U.K., North America, Japan, Israel and Russia later this year (10).

Osbourne has previously insisted he is healthy enough to carrying on making music for years to come, saying, "I recently went for a medical; my doctors gave me a full bill of health."

But the 61 year old has now admitted he has concerns about touring the globe.

He tells Kerrang!, "Back in the '70s with Sabbath, a long tour was about eight weeks. Now in my 60s I have to do 18 months! If it starts to play on my health, I'll think twice about it."