It seems she got her endorphins pumping!

Reese Witherspoon threw on her cutest workout outfit to catch a yoga class in Brentwood yesterday, and the actress was smiling and in a great mood after her session.

The blonde beauty seems so wholesome and squeaky clean, it's hard to imagine her playing a troubled divorcee who dabbles in heroin and one-night stands in her new film . "Nobody knows what goes on behind closed doors, but I think there’s a general sense now that I’ve lived a pretty textured life. So many of the things that Cheryl [her character] goes through in the book I’ve been through, you know? I’ve been married, I’ve been divorced. I haven’t lost my mother, but my mother’s mother died in a very similar way, of an aneurysm very suddenly.. Cheryl has this idea that the things that have happened to you are part of you. There’s something really beautiful about that idea," she recently explained to Vogue about being drawn to her latest role.

She's probably beaming because she knows she might have another Oscar winning performance on her hands!