It takes a lot to beat Anastacia. The 5ft 3 singer might not look like she could take on the world but spend one minute in her company and it becomes clear why this hugely successful star seemed to take even breast cancer in her stride.

Looking lithe and healthy, hair immaculate, make-up perfect, the 31-year-old is a force of nature, rather than the Freak Of Nature of her debut album's title.

She has just completed a demanding world tour with her typically unflinching and dedicated manner.

And rather than drain her after her year-long battle with breast cancer in 2003, which was followed by the weighty demands of promoting her third album Anastacia throughout 2004, the tour actually gave the New York-born star a new lease of life.

"It's amazing what a tour can do for one's physical spirit," she says. "People ask me how many sit ups I do and I'm like, 'Dude, none'. I never go to the gym. People tell me they could wash clothes on my stomach and I'm like, 'I know, I've been jumping on stage for a few months'.

"It was hard getting into it because physically I wasn't quite as healed as I wanted to be. But it helped. Even though I may have dropped five pounds, my body is solid. I'm like a rock now, which is great.

"And I am going to stay like this because I know it's good for my spirit. My spirit finally came back health-wise. I really missed that. I was so detached for so long, probably even before the cancer came, so it's really nice to have my self back.

"I'm really excited. I feel younger, I feel happier. Things are great and it's nice to feel that way and not have much work to do," she laughs. "I feel like I can run marathons and now my frickin' train is slowing down."

As we head into the later part of 2005 Anastacia's music career is beginning to wind down for a while. In November she releases her first greatest hits collection, which is yet to be titled. It will be preceded by an as yet undecided new single, one of four new songs that feature on the hits collection.

"One of them people have heard already, the collaboration with Ben Moody we did for the Fantastic Four soundtrack," says Anastacia. "There's another duet with an Italian singer called Eros Ramazzotti who is unbelievable. He's sold millions of records in his life, and the character of his voice is very interesting.

"He asked if I wanted to do a duet for his album and I liked the song so much, the energy of it, I wanted to put it on mine as well. Then the other two songs are absolutely new Anastacia songs."

Promotion for the greatest hits will take Anastacia into 2006 but then she's taking a well-earned break from the music business for a while. She says not to expect a new album from her until 2007 or even 2008.

"At the end of the day my last album came out almost two years ago and this whole year I've been touring," she explains. "I've got to go away. But I'm not going away officially. There's all these little things that I'm doing that you'll end up seeing but won't have anything to do with music."

But she's staying cagey about exactly what these projects are.

"Oh honey I'll tell you about it later," she laughs. "I'll tell you about it when we can put it to the press. I'm not ready to talk about it yet, even though the papers are signed. It's just, you know, endorsements, different things."

But for now we'll be seeing plenty of Anastacia. The singer has been expanding her professional horizons already by taking on the role of judge for MTV's new X Factor-style talent search show MTV A Cut.

The music channel held auditions in five European countries --Denmark, UK, Italy, Holland and Germany - looking for ten bands (of any genre) with enough talent and potential to put into a week-long training camp.

From those ten Anastacia and a variety of industry specialists have to pick two acts for the final, the winner getting the opportunity to open for Anastacia on tour.

"There were tears," she says. "From me! From me every day! Oh my God, thank God that MTV got hardly any of the tears that I shed. It was very hard for me because I really didn't want to crush any of these poor people's dreams.

"But I also wanted to keep the integrity of the show and I felt like I was battling MTV and battling my own spirit because I didn't want to get reality show-based. I didn't want them to throw a hot tub in there and do the whole reality show shebang.

"I wanted them to keep it about the music and it was hard for me to do that because reality shows come easy to MTV. I think it was hard for them to trust in me that we didn't need all that here."

Anastacia got involved with the show as it gave her an opportunity to repeat her own history with a new talent. She herself was discovered on MTV US's talent show The Cut in 1998.

Her performance caught the attention of a number of record companies and eventually she signed with Epic. Now the same is happening with acts from MTV A Cut - four of the bands are currently being chased by record labels.

"Some of them are being pursued, shall we say," says Anastacia.

"I'm not stupid, honey," she laughs. "I know what to look for. A isn't at the front of the alphabet for no reason. Hello!"