This marks the second time the Caped Crusader will appear in the ad campaign.

Christian Bale plays Batman in "The Dark Knight," due in U.S. theaters July 18. The new Batman milk ads are to debut this weekend.

The ad copy reads: "Others reload. Batman refuels. Research suggests that milk's unique mix of nutrients can help athletes recover after exercise. And its protein can help build muscle. So train hard and drink lowfat or fat free milk, because the Batmobile isn't the only thing that needs to refuel."

The Body by Milk Campaign and DC Comics said they are holding a Batman Refuels Sweepstakes, the winner of which will have his or her likeness drawn into a Batman comic book.

More information about the contest can be found at http://www.bodybymilk.com.