Carrie Underwood spent three days in a German hospital after falling ill.

The 'Before He Cheats' hitmaker had to be treated in Germany after contracting a ''viral thing'' whilst touring Europe.

Speaking on The Tonight Show Starring Jimmy Fallon, she said: ''I don't cancel shows. Like, I will drag myself onto the stage and perform if I have the flu or whatever, but in the U.K. we had to cancel a couple of shows. Basically I got a viral thing and I woke up and I had vertigo. I could not stand up. It was crazy. I ended up in a German hospital for three days. They were so sweet and so nice and we were like in our room trying to learn German and communicate with the people. I didn't learn anything.''

Meanwhile, Carrie previously revealed she sees fitness as her ''therapy''.

She said: ''I feel like it's my therapy everyday. I don't go get massages, I don't go get facials. That would be great. I might get a massage twice a year - some Mother's Day present or something, which I literally have a gift card for that, that's like two years old that I have not used for Mother's Day. But, that's my thing. I don't need vacations even. I'm like, 'Honey, you can give me like an hour, I'm good. You don't have to take me out. It's fine.' That's kind of my therapy. I feel like a lot of what I do is physically demanding.

''It is demanding being on stage, and especially some of the songs that I write and sing are really hard, and I need that. I need to be at my peak. I need to be able to sing and walk across the stage without being winded. And I'm doing it in heels, which makes it five times as hard, so I feel like that's just something that makes me a better person, a better performer. It just makes me feel better about myself. It makes me feel better. I need that in my life.''