Katherine Heigl's 'Shelter Me' Trailer - Watch Now!

Katherine Heigl gets ready to feel the burn as she heads into the gym for a workout on Saturday (May 5) in Studio City, Calif.

The 33-year-old actress had a boxing lesson earlier this week with world champion boxer Terry Norris!

PHOTOS: Check out the latest pics of Katherine Heigl

Katherine has recently gotten involved with a PBS series called Shelter Me, which follows the lives of shelter pets as they transition into their new homes. Check out the trailer below!

10+ pictures of Katherine Heigl heading into the gym for a workout…