Got power serve?

Ana Ivanovic is one of the latest celebrities to join the "Body By Milk" advertising campaign.

In the ad, Ivanovic says: "Power Serve. I give it my all, so milk's the perfect match for me. Milk is a great choice after exercise, with protein to help build muscle and a unique mix of nutrients to refuel. So train hard and drink lowfat or fat free milk. That's what I call a nice return."

According to the women's tennis website, OnTheBaseline.com, Aaress Lawless notes that Ivanovic was, at press time, ranked number four on the Sony Ericsson WTA Tour, right below Serena Williams and two places above Maria Shaparova.

Ivanovic said: "I'm very happy to be part of the ‘got milk?' campaign. It's always an honor to be asked to take part in something positive, that promotes a healthy lifestyle.

Making sure you get enough calcium is an important part of your diet; the ‘got milk?' campaign is a fun way of publicizing it."

The National Milk Mustache "got milk?" ad campaign was created to encourage teens to drink milk every day, and to be active and eat right to stay lean and healthy.

Milk contains nine essential nutrients including calcium and vitamin D to maintain bone strength and high-quality protein that helps build muscle when combined with exercise.

The USDA recommends three 8-ounce glasses of lowfat or fat-free milk each day, which provides about half of the protein teenagers need each day.

Body By Milk® is part of the National Milk Mustache "got milk?" Campaign, an education program focused on the health benefits of milk managed by the Milk Processor Education Program (MilkPEP) in Washington, D.C.