Having a good strong core is important in order to support not only your spine but your whole body. Therefore it is important that if your just beginning a yoga practice that you spend some time strengthening your core.
Your core consists of a number of muscles, not just the rectus abdominis muscle (the muscle that is responsible for producing your six pack.) In fact the rectus abdominis has quite a limited use. The core muscles consist of lots of muscles, including the gluteals, the hip flexors and adductors, the obliques, the transverse and rectus abdominis and the deep spine muscles that run along the spine, called the erector spinae and the multifidus muscles. These muscles are responsible for stabilising and providing strength to your trunk and your pelvis. Weak core muscles can result in poor posture, muscles imbalances, poor athletic performance, and can be the major cause of back pain.
Here are the six best poses to strengthen your core.. Click on the links to get a detailed description from the yoga journal website on how to perform the safely.