Starting Position: Lie in a supine (on your back) position on a mat with your knees bent, feet flat on the floor and heels 12 - 18" from your tailbone.
Place your hands behind your head, squeezing your scapulae (shoulder blades) together and pulling your elbows back without arching your low back. This elbow position should be maintained throughout the exercise. Align your head with your spine, but allow it to move into slight flexion (moving the chin towards the chest) during the upward phase of the exercise.
Upward Phase: Exhale, contract your abdominal and core muscles and flex your chin slightly towards your chest while slowly curling your torso towards your thighs. The movement should focus on pulling your rib cage towards your pelvis (the neck stays relaxed while the chin is tucked towards the neck). Your feet, tailbone and lower back should remain in contact with the mat at all times. Continue curling up until your upper back is lifted off the mat. Hold this position briefly.
Downward Phase: Gently inhale and slowly uncurl (lower) your torso back towards the mat in a controlled fashion keeping your feet, tailbone and low back in contact with the mat.