Starting Position: Lie on your back on a mat with your knees bent, feet flat on the floor and arms spread out to your sides with your palms facing down. Gently exhale. Engage your abdominal/core muscles to support the spine. Slowly lift your feet off the floor, raising your knees directly above your hips. Bend the knees to 90 degrees. Hold this position and breathe normally. Use your arms as a base of support.
Upward Phase: Exhale, and slowly raise your hips off the mat, rolling your spine up as if trying to bring your knees towards your head. Avoid any change in the angle of your knees during the roll-up. Use your arms and hands to assist with maintaining your balance and continue to curl-up until your spine cannot roll any further. Hold this position briefly.
Downward Phase: Gently inhale. With control, lower your spine and hips back to the start position.
Proper form is important when performing this exercise to prevent excessive stress on your low back. When returning to your starting position during the repetitions, control your leg movement. Do not allow your knees to move past your hips, but instead return to a position directly above your hips. Since the abdominals connect the rib cage to the pelvis, the emphasis of the movement should be on pulling your pelvis upwards towards your rib cage.