Alicia Keys is a Secret Runner  4/5/07

R&B star Alicia Keys has a sporty new hobby - she has fallen in love with marathon running.

The singer-turned-actress discovered the joys of long distance running while training for her role in movie Smoking Aces, and became so hooked she traveled to Greece to sweat through the original marathon route.

Keys explains, "I just ran a marathon - I did that in my spare time. I like to challenge myself.

"I did the original marathon, which was very exciting.

"It kind of started with Smokin' Aces because I was training in a way that I'd never trained before. I started doing a lot of running and I really got into that.

"The cardio side of it just put my mind at ease and after everything with Smokin' Aces I just kind of woke up and thought, 'I want to run a marathon!' So we started preparing for it and I did. It was weird. It was the weirdest sensation."