Roger Daltrey isn't allowed to do consecutive concerts.
The Who legend had a pre-cancerous growth removed from one of his vocal cords in December 2009, and ever since he's made sure to take good care of his voice.
Due to the terms of his insurance, Daltrey - who released solo album 'As Long As I Have You' today (01.05.18) - has to have a day off after one concert.
In an interview with The Sun newspaper, the 74-year-old rock legend said: "I used to overdo it a lot over years and years of singing with The Who.
"We would do three consecutive nights of three-hour shows, one night off, then we'd do the same again. That was insanity.
"I ended up with a pre-cancerous throat condition but it wasn't malignant so I got lucky.
"The guy who looks after me now has kept my voice in really good order.
"My insurance won't let me do two shows on the trot so every time I do one, I have a day off.
"It means the next time I do a show, I can give it 100 per cent and I'm not wearing myself down.
"I'm really strict with my routine. And you have to be because I'm not a robot, I'm on stage naked.
"If I don't look after the instrument, and I am the instrument, then I'm f***ed."
The 'Pinball Wizard' hitmaker has no plans to retire from performing live anytime soon, but as soon as he is no longer able to hit the high notes, he'll bow out.
He said: "If my voice goes, I will stop.
"I've always said that you don't retire from this business, the business retires you.
"But I'm singing better than ever at the moment and I will know immediately when I can no longer do that.
"If I have one show which is not quite right, then another and another, I'll stop."
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