After having a baby, it takes time to regain core strength, especially if you had diastasis recti or a C-section. But don’t worry—after you’ve taken time to heal and your doctor gives you the go-ahead, Jillian Michaels is here to help you start rebuilding your abdomen muscles and start feeling like yourself again.

Wait at least six weeks postpartum to do any type of strength training—and at least three months if you had diastasis recti or a C-section.

In this video, Jillian demonstrates the Bird Dog. Start on all fours in a tabletop position, placing shoulders directly over your wrists and hips over knees. Then extend opposite arm and leg, engaging the stomach to help you balance. Pull your elbow and your knee under your torso to touch, and then extend them again. Repeat as many times as possible (while maintaining good form) for 15 seconds, and then do the same on the other side.