Never ceasing with her strict workout regimen, Reese Witherspoon made her way to the gym in Brentwood, CA on Thursday (December 12).

The "This Means War" starlet was a beauty in black, dressed in a hoodie and yoga pants, carrying her coat and water bottle, ready to get busy with her fitness routine.

In related news, the 37-year-old beauty is working on an upcoming movie entitled, "The Intern," coming at us from "The Holiday" director Nancy Meyers.

Slated for release in 2015, the comedy's synopsis tells us that, "The owner of a successful fashion website bonds with the elderly intern her company's hired."