Sophia Bush Works Out Her Gluteus Maximus

One Tree Hill star Sophia Bush stays in shape, working her glutes by doing lunges on Tuesday in Los Angeles with the help of celebrity trainer Harley Pasternak, who’s recently been helping Jessica Simpson get her killer calves.

Harley‘s celebrity clientèle has included Alicia Keys, Halle Berry, Eva Mendes, Jessica Simpson, Kanye West, Orlando Bloom, Mandy Moore, Jane Fonda, John Mayer, Vanessa Williams, Eve, Michael Chiklis, Rachel Weisz, Sophia Bush, Zach Braff, Val Kilmer, Robert Downey Jr., Ben Foster, Jim Caviezel, Benjamin Bratt, Stephen Dorff, Common, Eliza Dushku, Rick Fox, Nia Long, Donald Faison, Jeff Goldblum, Enrique Murciano, Brendan Fraser, Claire Forlani, LL Cool J, Juliette Lewis, Milla Jovovich and Ray Liotta.

DAYUM! Is there a more established celebrity fitness guru?!

15+ pictures inside of Sophia working out her glutes with Harley…