Lie on your back with your knees bent, feet hip-width apart and abs drawn in. Flex your left foot, pressing your heel into the floor. Keeping your pelvis still, inhale, then exhale as you use your deep abdominal muscles to push your left heel away from your body, keeping the knee slightly bent [shown]. Return to starting position. Alternate sides, doing 5 slides on each side, working up to 10. Do these first three exercises together and in order for the next two weeks, then add move 4.
Strengthens the transverse and lower back, supporting your core.