
Volleyball Olympian Kerri Walsh has an athlete's abdomen. Here's how she gets it:
In addition to practicing on the volleyball court, three hours a day, Walsh also practices pilates three days a week. She feels that it has given her greater flexibility, strength and stability.
Her favorite pilates move is called The Teaser.

I am not fit/advanced enough to do a Teaser in its full form. I have done--with great difficulty!--the beginner version shown in this video's second part.(The one with the bent knees, ball between knees, and using the roll-down/push-through bar.)
Quote taken from a blog entry over at Diets in Review
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