Hilary Duff is a Gym Rat

Hilary Duff gets in another private gym session with celeb trainer Harley Pasternak on Tuesday afternoon (July 13) in Los Angeles.

The 22-year-old actress was accompanied by her fiance, Mike Comrie.

Tonight is the grand-finale of The Hills, beginning at 8 p.m. on MTV. The show and its predecessor, Laguna Beach, helped spark some artists’ music careers. Hil‘s song “Come Clean,” co-written by Kara DioGuardi and John Shanks, was the theme song for Laguna. The song peaked at #9 on the Billboard Pop Songs chart!