What's the cover charge?

Can you spot the heart monitor?

That's the initial reaction driving past the Eagles' practice fields, hearing the music, the whistles and seeing the mass of humanity.

It looks more like a dance party than a practice.

"I love it," tight end Brent Celek said. "It makes it fun. When you’re not out on the field doing actual plays it just keeps you going. It keeps you interested in what’s going on out there. You’ve got some background music. It’s like sitting in a nice restaurant and having background music."

Celek, quarterback Michael Vick and several players practice with heart monitors. The training staff studies the results hoping to keep players functioning at or above a consistent level.

Make no mistake, the rock, rap and other forms of music have everything in the world to do with Kelly's desire to practice up-tempo.

But at the same time, you hear it, you feel it ... and you cannot help but want to dance after taking it in.

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