Nick Lachey and Vanessa Minnillo Photo by: Marion Curtis / Startraks
Vanessa Minnillo: Nick Said 'I Love You' First | Nick Lachey, Vanessa Minnillo
Luckily for Vanessa Minnillo, life doesn't always imitate art.

Case in point? In Disaster Movie, hitting theaters Friday, Minnillo's cheerleader character just can't get her boyfriend to say "I love you."

"He just can't drop the L-word," Minnillo, 27, tells PEOPLE of her character's commitment-challenged boyfriend. "And what a girl wants more than anything in the world is for their boyfriend to say 'I love you.' "

But, says Minnillo, her real-life beau Nick Lachey, 34, doesn't have any similar hang-ups: "The L-word is not thrown around by men as easily as it is by women – but I didn't say it first! He's very loving. We're very open and vocal."

While Minnillo and Lachey may be in sync when it comes to their love for each other, their attempt to exercise together is not so harmonious.

"We used to work out together, but we stopped," says Minnillo, laughing. "We're doing different things. And the guy runs forever! Like, I swear, he's running 11 miles a day. I can't run. That's the one thing I can't do, because I feel like the further I jog away from my house, the further I have to jog back!"

To read more of Minnillo's interview, pick up this week's PEOPLE, on newsstands Friday.