Robbie Williams stopped eating in preparation for his album's promotional video.
The 42-year-old singer released a promotional video for his new album 'Heavy Entertainment Show' in which he appeared shirtless in a boxing ring, but the star has now revealed his toned physique in the video came at a cost to his health.
Speaking to The Sun newspaper, the former Take That star said: "I've got this bad back, so I haven't been able to do any training. But all it takes is not eating. Who knew?
"I'm pretty muscular, naturally very muscular, so if I watch what I eat it kind of does the trick. But now I'm hungry constantly.
"Hungry, confused, depressed. It's like wrestling a very angry and needy bear all the time.
"In fact, so much so, I think I'm just going to work on my personality and eat what the f**k I want.
That's what I've learnt from the Russians. They don't give a f**k -- that's the spirit of partying and I tip my hat to them."
The 'Let Me Entertain You' hitmaker - who was previously known for his party lifestyle - would now much rather stay at home with his wife Ayda Field and their two children, four-year-old Theodora Rose, and two-year-old Charlton Valentine.
He said: "I'm still a very, very naughty boy gone good. And the naughty boy comes out to play every now and again.
"In my dreams, actually, every night. Seriously."
But the time spent at home has given Robbie time to worry about his music, and after his new single 'Party Like a Russian' flopped in the charts, he says that he "panics" about how his music will be received.
He added: "I worry that the oxygen needed for my songs to be heard might be taken away.
"My brain's resting position I think is panic and worry. It's never really happy. It's what keeps you propelling forward. You don't rest at happy."
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