The Great Wall works the entire abdominal area with focus on the upper abdominal region.
|How to do:
1. Stand straight up.
2. Concentrate as hard as you can on your abs.
3. Tense your abs as hard as possible. Put all your energy
4. Maintain the incredible tension for a count of 6 and relax.
5. Immediately tense the abs again.
6. Continue this cycle until failure.