- I have yet to find an abdominal exercise that puts your abs under more duress, especially when done all the way to the floor.

- used by gymnasts to practice the "hollow" position, this ab exercise is very difficult when done correctly
- maintain a hollow position, your back rounded and rock back and forth on your spine

- the "secret" behind strong lower abs. Press your lower back tightly against the floor when doing any lower abdominal movement.
- the progression from least difficult to most difficult will provide you with lower ab strength and neuro-musuclar coordination.

- more difficult - keep your arms straight.
- more, more difficult - keep your knees straight and bring toes to the bar

- hold as long as possible with stiff legs and arms. Shoot for 3 minutes!

- The ultimate dead hang pull up. Fantastic for your abdominals as well!
- Maintain a strict L position with your legs as you do pull ups.

- keep your heels next to your butt as you roll up and your lower back on the bench (no arch) as you lower your legs on the way down

This is a great basic movement to get a feeling for what is meant by "hollow" and what is meant by arched. Having facility with pelvic rocking is essential to good control of the core and torso for all movement - from squats and deadlifts to push ups and leg lifts. It is also great for loosening up tight lumbar erectors.