The 42-year-old film star recently opened up to Men's Fitness about his impressive physique.
He said: 'I don't really enjoy training. People say it's addictive, but I'm like: 'Not so much'. If I wasn't getting paid or didn't have a character like Wolverine to maintain, I would be a tall, lean, fit guy.'
The actor added that it has got harder to get his body in shape as he's got older.
He said: 'Over the past three or four years it's gotten a lot tougher. I have to eat a stricter diet. I have to train even harder. I can't get away with what I used to.'