How Well Do You Know Your Abs?

Your abdominals are (literally) at the center of everything. Here's what you need to know to use them smartly and safely during your yoga practice and the rest of the time, too.

- GINA TOMAINE

If you hear "a strong core," you may instantly think of sharply defined abs. You're not alone. "When talking about our core,' we often focus on the parts that we can see or have been told by society that indicate a strong belly-the rectus abdominis, also known as the 'six-pack' muscle," says Kristin Leal, a New York-based yoga teacher and the author of Meta Anatomy: A Modern Yogi's Practical Guide to the Physical and Energetic Anatomy of Your Amazing Body.

But the truth is your core is a central structure of your body that's key to your overall health. All of the abdominal muscles-plus the muscles in your back and pelvis work together to help keep your body stable and balanced, as well as protect your spine. Your core is doing a ton of structural work, even if you aren't wearing washboard abs. The best way to respect all of the effort your abs are making to keep you upright is to learn their parts so you can move with care.

Abs Anatomy

There are four main abdominal muscles, says Richelle Ricard, yoga teacher and author of The Yoga Engineer's Manual: The Anatomy and Mechanics of a Sustainable Practice.

Rectus abdominis: A pair of long muscles that run from the sternum to the pubic bone, they allow you to flex forward. The appearance of a "six-pack" or "eight-pack" comes from the tendinous bands (inscriptions) that cross the muscles.

Transversus abdominis: This is your deepest ab muscle, which wraps around the waist to stabilize and support the spine.