Charlize Theron looked nothing like the statuesque movie star we're used to seeing as she headed out on a hike with her adorable son Jackson in Runyon Canyon yesterday (March 15).

Accompanied by her dogs and a friend, a dressed-down Theron was all smiles and appeared revved up for a workout. The Oscar-winning actress, 37, sported a loose-fitting white and blue striped tank top and unflattering sweatpants -- clothing items she rarely dons in public. What happened to the skintight leggings and clingy T-shirts, Charlize?

Still, the busy mom is most likely not worried about what she looks like -- as long as she's squeezing in a good workout. Last year, the South African beauty told Vogue, "I’m sure there are women who never have to worry about what they eat. But I do. I exercise a lot, and I hike a lot. My mom and I hike at least three times a week."

Check out Charlize's workout attire below:

charlize theron photos

charlize theron photos

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  • LOS ANGELES, CA - MARCH 17: Actress Charlize Theron lifts her drink for a toast during The Human Rights Campaign (HRC) Los Angeles Gala at the Ritz Carlton/JW Marriott on March 17, 2012 in Los Angeles, California. (Photo by Frederick M. Brown/Getty Images)

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