"It's extremely difficult to perform with, because it's like running a marathon with ankle weights on," the singer said.

Miley Cyrus has a "very large polyp" on her vocal cord - but is "not willing" to have it removed in case it changes the distinctive low tone of her voice.

On 'The Zane Lowe Show', Cyrus revealed she has a "large polyp" on her vocal cordsMiley Cyrus revealed the "unique anatomy" ...