Mario Lopez might be one of the busiest guys working in Hollywood, but he swears he's taking a very hands-on approach with his four-week-old daughter Gia.

The 'Extra' host tells PopEater that he's even helping girlfriend Courtney Mazza in the diaper-changing trenches.

"I'm the go-to-guy for diaper changing," he says, speaking from a ping pong-themed birthday party thrown for him by Celsius energy drink -- the couple's first public outing since Mazza gave birth last month. "I've gotten pretty good at it."

But just how many can he handle?

"I'm good for at least a couple a day -- one in the morning and one later on," says Lopez. "But she goes a lot."