ANCHORAGE, Alaska: Levi Johnston is going for the ultimate exposure - the 19-year-old father of Sarah Palin's grandchild will pose nude for Playgirl, his attorney said late on Wednesday.

To get ready for his close-up, Johnston is training three hours a day, six nights a week at an Anchorage gym with a local body builder.

A formal agreement hasn't been reached with the online magazine, but the photo shoot is a "foregone conclusion," said Johnston's attorney, Rex Butler.