Singer. Songwriter. Philanthropist. Entrepreneur. Actress. Producer. Beyoncé may be the hardest-working woman in showbiz.

Take the four days leading up to MTV's recent Video Music Awards.

Beyoncé wraps a run-through of her Radio City Music Hall performance at midnight Thursday evening. Friday morning at 10 a.m., it's déjà vu as she returns to rehearsal mode. A dressing room break is anything but: chats with MTV personnel about show logistics segue into an editing session for her next project -- a DVD culled from a summer stand at the Wynn Las Vegas. Later that evening, Beyoncé makes a surprise appearance at husband Jay-Z's Sept. 11 Madison Square Garden show. Then right after the VMAs, Beyoncé and her alter ego Sasha Fierce catch a flight to Australia to kick off the next leg of their I Am... world tour.

As she ticks off her jam-packed schedule, an unfrazzled Beyoncé dismisses her multitasking with a laugh: "It's just one of those grind weeks. It will be less hectic when I'm in Australia." A world tour is less hectic? As you exhale and ponder that irony, it becomes clear that this is someone who thrives on hard work and fierce determination. Before slipping back into her signature stilettos, Billboard's 2009 Woman of the Year shares how she balances work and relaxation, feeds her philanthropic passions and envisions her future.

The average person can't keep up your pace. How do you it?

I'm an all-or-nothing type of woman. Either I'm doing absolutely nothing and relaxing -- reading a book, sitting by the ocean and not answering any questions -- or else I'm hands-on and giving 100%, working really hard.

I was just on vacation for three weeks after touring for a couple of months. I have to schedule time to rest, rejuvenate and get inspired to work again. Now I'm definitely rested and thank God I had the rest -- that's the only way I would be able to get through a week like this. After three weeks without giving any answers or approvals and no performing, I came back like, "Yes! I'm ready to work!" [laughs]

How do you flip the switch from Beyoncé to Sasha Fierce on tour?

It's a lot easier than it used to be since I've put so many hours into performing; I can make the transition from Beyoncé to Sasha Fierce really fast. I don't have any crazy rituals beforehand. I get in maybe two-and-a-half to three hours before each show. I do my makeup on tour myself and get my hair done. Then we all come together, say a prayer and do a little stretch. I also do meet-and-greets during which I meet a lot of my fans. I usually meet children from the Make a Wish Foundation. I've basically given them an open invitation whenever anyone wants to come. That's always a highlight of the day for me.

On my days off from the tour, I do a lot of sightseeing. I love to visit churches and museums all over the world. The architecture in America is amazing but in Europe, there's so much history. I also started riding a bike on my days off with others like my assistant and stylist. It's amazing how I'm able to ride around on a bike. People kind of see it's me but since I'm on a bike, they think, "No, it's not her." And by the time they realize it's me, I'm already gone. It's great to do something normal every day. It keeps me grounded.

What do you do to maintain your tour stamina? I heard a rumor that you run on a treadmill in heels and sing.

[Laughs heartily] No, I don't run on a treadmill in heels. That's a bit extreme. But I do practice my choreography in heels. And I have a rule that when I have my heels on, everyone has to have their heels on too. Sometimes the dancers are like, "Oh, God, we hope Beyoncé comes in late," because I'll go all day. And in the end, I'll have blisters and my toes will have bruises. It's really hard sometimes. I still do all the boring things that everyone else does in regular workouts like squats and the treadmill. But I mainly get in shape from doing the choreography during those long 12-hour rehearsals for two months before a tour.

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