Sir Paul McCartney says eye yoga has helped to improve his vision

Speaking to Jessie Ware on her Table Manners podcast, she said: "I learned off some yogi in India. He explained that your eyes are muscles. Your ears aren't, so you can't exercise your ears.

"But your eyes, you can. So head still. And then you look up as far as you can, one, two, three, go back to the middle, then down, back to the middle. You do three lots of that then go to the left and the right. Now you've got a cross, up and down, and sideways, now you do the diagonals."

Paul has a "very definite routine" when it comes to working out.

He said: "I have a very definite routine. I get on the mat, and I do a bunch of stuff there. Then, I move over to a cross-trainer [or] do a bit of running. It’s not a huge workout, but it’s good. I like it."

Paul regularly impresses other gym goers by doing headstands.

He added: "If I’m in a gym and all the big guys have got big weights and they’re doing all the big stuff, at the end I do a headstand. And they come over to me [and say], 'That’s pretty impressive man.'"

The 78-year-old singer is a vegetarian and is grateful there are so many options available.

Speaking about his diet, he said: "You can get loads of vegetarian options these days, so it’s not like it was like in the old days when you just got the boiled sprout."